Home/Past Papers/Punjab / UHS/Uhs Mdcat 2018

Uhs Mdcat 2018 — Solved Past Paper with Answers

All 220 MCQs from Uhs Mdcat 2018, solved with the correct answer highlighted and a full explanation for every question. This is a free MDCAT Punjab / UHS past paper — no signup, no ads. Practise it interactively in timed mode, drill more with free MDCAT MCQs, or browse all Punjab / UHS papers.

Attempt this paper interactively →

Q1. Choose the BEST Option.That is just an example of what I complain _.

  • A. Of
  • B. Off
  • C. To
  • D. With

Explanation: Of is a preposition that indicates relationships between other words, such as belonging, things made of other things, things that contain other things, or a point of reckoning. The object of "of" must be a problem of some kind: you could complain of a headache, an unreliable web server, an unfaithful spouse, mistreatment by police, etc.

Why the other options are wrong
  • B. 'Off' is usually used as an adverb or a preposition. In both cases, it indicates separation or disconnection. For example: She got off the bus at the next stop.
  • C. We can use to as a preposition to indicate a destination or direction: We're going to Liverpool next week. Does he want to come to the park with us?
  • D. With means 'in the same place as someone or something' or 'accompanying': I don't like tea with milk. There was a free phone with the car.

Q2. Choose the BEST Option.The region _ which they were passing was known as the Land of Thirst and Death.

  • A. Through
  • B. By
  • C. In
  • D. From

Explanation: Through can be used as a preposition, an adverb, and an adjective. It has several meanings, including “from one side to the other,” “from beginning to end,” and “during an entire period”: He rode his bicycle through the door and onto the street. You have to read the book through if you want to be prepared for class.

Why the other options are wrong
  • B. By means ‘as a means of’ something or someone. This preposition often comes in a passive sentence.Example:Do you travel by bus/train/plane/bike? He was undone by me. The letter was written by him.
  • C. In (to indicate a location)- I am in my friend’s place now.In (used while doing something) — The tagline should be catchy in marketing a product.In (to indicate opinion, belief, feeling, etc.)- I believe in hardwork.In (specify day, month, season, year) — I prefer to do Maths in the morning.The new academic session will commence in March.In (to indicate colour, shape and size) — This dress comes in four sizes.
  • D. 'From' is used to show where somebody/something starts, what the origin of somebody/something is, how far apart two places are, somebody’s position or point of view etc

Q3. Choose the BEST Option.I know how to _ a throat for inspection.

  • A. Force
  • B. Prepare
  • C. Expose
  • D. Open

Explanation: Text From (Use of Force) "To expose" is defined as to make something visible or known.

Why the other options are wrong
  • A. This means to make someone do something against their will or to exert physical strength. Forcing a throat for inspection would be inappropriate and medically incorrect.
  • B. This means to make ready beforehand for a specific purpose. While you can prepare a patient for an inspection, it doesn't directly refer to the act of making the throat visible for inspection.
  • D. This means to move something from a closed position to a more accessible one. While you might open a mouth, "expose" is more precise when referring to the throat specifically for inspection purposes.

Q4. Choose the BEST Option.It is better for me to _ than to shed the blood of an innocent boy.

  • A. Died
  • B. Die
  • C. Had died
  • D. Have died

Explanation: The sentence is structured in a way that requires an infinitive verb form ("to die")."Die" is the infinitive form of the verb that correctly fits after "to" in this sentence.

Why the other options are wrong
  • A. "Died" is the past tense of the verb "to die," which does not fit the infinitive form required by "to."
  • C. "Had died" is the past perfect tense, which is used to indicate an action completed before another past action. It doesn't fit the structure needed here.
  • D. "Have died" is the present perfect tense, indicating an action that occurred at an unspecified time before now. It doesn't fit the infinitive structure required by "to."

Q5. SPOT THE ERROR: In the following sentence some segments of each sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.The most important and the least difficult thing to achieve is a desire amongst individuals to limit the size of family.

  • A. The most
  • B. The least
  • C. Is a desire
  • D. amongst individuals

Explanation: Text from ( Hunger and population explosion). Reading this sentence, we understand it talks about reducing the size of a family. While it is most important, it is also a very difficult idea to propagate 'the least' should be replaced by 'the most' so it fits in with the meaning of the sentence.

Why the other options are wrong
  • A. "The most" is perfectly positioned in sentence so it is not the incorrect part of given question.
  • C. This portion doesn't contain any mistake so it is incorrect.
  • D. There is no mistake in this portion of sentence so it is not correct option.

Q6. SPOT THE ERROR: In the following sentence some segments of each sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.There is terror from the outset and there are all the components necessary to create a melodrama -- a dimly lit bus station, the storm accompanied by flashes of lightning and the promise of violent action or emotion.

  • A. From the outset
  • B. There are all
  • C. The storm accompanied
  • D. The promise of violent

Explanation: Text from (Book # III, Play # 1). The best way of solving this question is to read the entire sentence in your head and decipher which part does not seem right.The sentence says a dimly lit station, hence similarly 'the storm' should be replaced by 'a storm accompanied by flashes of lightning....'

Why the other options are wrong
  • A. It is correct part of sentence.
  • B. It is correct part of sentence.
  • D. It is correct part of sentence.

Q7. SPOT THE ERROR: In the following sentence some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.The king feels disturbed and on hearing these words he could not control his tears

  • A. Feels
  • B. And on
  • C. These words
  • D. Could not control

Explanation: Text from (Book # I, Lesson # 08, Story # 3, Para #4, Line 1). The sentence is a simple past tense sentence hence use 'felt' instead of 'feels'.

Why the other options are wrong
  • B. It is correct part of sentence.
  • C. It is correct part of sentence.
  • D. It is correct part of sentence.

Q8. SPOT THE ERROR: In the following sentence some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.He had earned the reputation of being a great jester, and jests were expected from him.

  • A. Of being
  • B. A great jester
  • C. Jests
  • D. From him

Explanation: Text from (Mr. Chips, Chapter # 16, Page No. 38, Para # 4, Line # 2). Expected from' can be appropriately used in a situation when one is anticipating to receive something, material or nonmaterial from someone. Example: 'The weekly sales report is expected from you' or 'A negative response was not expected from her after such good news.' 'Expected of' should be used when you believe that someone is capable of living up to a certain characteristic or adopting a typical behaviour. For example, 'This degree of good behaviour is expected of him.' or 'It is expected of the company to appropriately share the corporate and social responsibilities.'

Why the other options are wrong
  • A. It is correct part of sentence.
  • B. It is correct part of sentence.
  • C. It is correct part of sentence.

Q9. SPOT THE ERROR: In the following sentence some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.He glances back at the door, then turns his attention once more towards the paper and begins going through it casually. No error

  • A. He glances
  • B. At the door
  • C. Towards the paper
  • D. Through it casually
  • E. No error

Explanation: Text from (Book # III, Play # 1, Theme Lines). There should be 'to the paper ' instead of 'towards the paper ' because 'to' is used for focus, for attention, for destination but 'towards' is used only for direction.

Why the other options are wrong
  • A. There is no error in 'He glances'
  • B. There is no error in 'at the door'
  • D. There is no error in 'through it casually'
  • E. Text from (Book # III, Play # 1, Theme Lines). There should be 'to the paper ' instead of 'towards the paper ' because 'to' is used for focus, for attention, for destination but 'towards' is used only for direction.

Q10. SPOT THE ERROR: In the following sentence some segments of the sentence are underlined. Your task is to identify that underlined segment of the sentence, which contains the mistake that needs to be corrected.However, by being so long in lowest format I gained an immense advantage over the cleverer boys.

  • A. However
  • B. Lowest
  • C. An immense
  • D. Cleverer boys

Explanation: here immense is used an an adjective to show the degree of advantage and so using the article 'an' is not grammatically correct.

Why the other options are wrong
  • A. This option is correct in the given sentence.
  • B. Text from (Book # II, Lesson # 11, Page # 45, Last Para, Line# 1). The question says that the individual was the longest in the format hence he had an advantage. Logically, if he was the longest in the group of the short people then he must have had an advantage.
  • D. This option is correct in the given sentence.

Q11. In the following question, four alternative sentences are given. Choose the CORRECT one.

  • A. The manager looked on me in some alarm.
  • B. The manager looked on me with some alarm.
  • C. The manager looked at me with some alarm.
  • D. The manager looked at me in some alarm.

Explanation: Text from (Book # II, Lesson # 7, My Financial Career). "Look at" means to direct your eyes in a particular direction. 'At' will be the most appropriate preposition to use here.With some alarm, means to look at someone with some caution and uncertainty. The best way to solve this question is to read each option in your head and then decide which one sounds the best and fits in well.

Why the other options are wrong
  • A. "Looked on" generally means to observe or watch over a period of time, which doesn't fit the context of a momentary reaction of alarm.
  • B. As with option a, "looked on" means to observe or watch over a period of time. This phrase still doesn't fit the context.
  • D. While "looked at me" is correct, "in some alarm" is less common and less idiomatic than "with some alarm."

Q12. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.ILK

  • A. Breed
  • B. Civilization
  • C. Origin
  • D. Culture

Explanation: Ilk: a type of person or thing similar to one already referred to. Breed: to be of some the heritage or nature. Civlization: a complex human society, usually made up of different cities, with certain characteristics of cultural and technological development. Origin: the point or place where something begins, arises, or is derived.

Why the other options are wrong
  • B. Civilization: a complex human society, usually made up of different cities, with certain characteristics of cultural and technological development.
  • C. Origin: the point or place where something begins, arises, or is derived
  • D. Culture: the arts and other manifestations of human intellectual achievement regarded collectively.

Q13. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.DUNCE

  • A. Brainy
  • B. Intellectual
  • C. Cautious
  • D. Oaf

Explanation: Dunce: a person who is slow at learning; a stupid person. Oaf: a man who is rough or clumsy and unintelligent. Brainy and Intellectual: Someone who is intelligent. Cautious: Someone who is careful about things.

Why the other options are wrong
  • A. Brainy and Intellectual: Someone who is intelligent.
  • B. Brainy and Intellectual: Someone who is intelligent.
  • C. Cautious: Someone who is careful about things.

Q14. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.HIATUS

  • A. Lull
  • B. Longing
  • C. Heretical
  • D. Veneration

Explanation: Hiatus: a pause or break in continuity during an activity. Lull: a temporary interval of quiet or lack of activity. Longing: a desire of achieving something. Heretical: holding an opinion which is different with what is generally accepted. Veneration: having great respect for something.

Why the other options are wrong
  • B. Longing: a desire of achieving something.
  • C. Heretical: holding an opinion which is different from what is generally accepted.
  • D. Veneration: having great respect

Q15. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.BUFFERS

  • A. Shocks
  • B. Shield
  • C. Support
  • D. Window

Explanation: Buffer: a person or thing that reduces a shock or that forms a barrier. Shield: a person or thing providing protection. Shocks: frightening someone. Support: a thing that bears the weight of something or keeps it upright. Window: a hole though a solid object which can allow you look inside and outside.

Why the other options are wrong
  • A. Shocks: a sudden upsetting or surprising event or experience
  • C. Support: a thing that bears the weight of something or keeps it upright.
  • D. Window: a hole through a solid object which can allow you to look inside and outside.

Q16. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.ENCUMBER

  • A. Clear
  • B. Spacious
  • C. Convenient
  • D. Strained

Explanation: Encumber: restrict in such a way that free action or movement is difficult. Strain: to tie up something, limiting movement. Clear: easy to perceive, understand, or interpret. Spacious: (especially of a room or building) having ample space. Convenient: fitting in well with a person's needs, activities, and plans.

Why the other options are wrong
  • A. Clear: easy to perceive,understand, or interpret.
  • B. Spacious: (especially of a room or building) having ample space.
  • C. Convenient: fitting in well with a person's needs, activities, and plans.

Q17. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.HECTOR

  • A. Harass
  • B. Helpmate
  • C. Hellish
  • D. Hefty

Explanation: Hector: talk to (someone) in a bullying way.Harass: make someone a subject to aggressive pressure or intimidation.Helpmate: a helpful companion or partner.Hellish: like hell.Hefty: large and heavy.

Why the other options are wrong
  • B. A helpmate is a companion or a helpful partner, which is unrelated to the meaning of "hector."
  • C. Hellish means extremely unpleasant or like hell, which is not the meaning of "hector."
  • D. Hefty means large, heavy, or substantial in size, weight, or amount, which is not the meaning of "hector."

Q18. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.NEXUS

  • A. Focal point
  • B. Success
  • C. Hinterland
  • D. Politics

Explanation: Nexus: a central or focal point, and a connection or series of connections linking two or more things. Success: the accomplishment of an aim or purpose. Hinterland: an area lying beyond what is visible or known. Politics: the activities associated with the governance of a country or area.

Why the other options are wrong
  • B. Success: the accomplishment of an aim or purpose.
  • C. Hinterland: an area lying beyond what is visible or known.
  • D. Politics: the activities associated with the governance of a country or area.

Q19. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.PERPETUATE

  • A. Skulk
  • B. Deviate
  • C. Eternize
  • D. Perish

Explanation: Perpetuate: make (something) continue forever.Eternize: cause to live or last forever.Skulk: keep out of sight.Deviate: departing from usual or accepted standards; deviant.Perish: die, especially in a violent or sudden way.

Why the other options are wrong
  • A. To skulk means to move stealthily or to hide in a sneaky manner, which is unrelated to "perpetuate."
  • B. To deviate means to depart from an established course or norm, which is the opposite of perpetuating something.
  • D. To perish means to die or to cease to exist, which is also opposite in meaning to perpetuate.

Q20. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.AUGUST

  • A. Local
  • B. Old
  • C. Venerable
  • D. Foreign

Explanation: August: respected and impressive. Venerable: held in a great deal of respect, especially because of age, wisdom, or character. Local: relating or restricted to a particular area or one's neighbourhood. Foreign: from somewhere outside.

Why the other options are wrong
  • A. This refers to something pertaining to a particular place or locality, which is unrelated to the meaning of "August."
  • B. While "August" can refer to something old, "venerable" more accurately captures the sense of respect and dignity associated with age or status.
  • D. This refers to something or someone from another country or place, which is unrelated to the meaning of "August."

Q21. In the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word.LAMPOON

  • A. Appreciate
  • B. Burlesque
  • C. Approve
  • D. Annoy

Explanation: Lampoon: publicly criticize (someone or something) by using ridicule, irony, or sarcasm.Burlesque: parody or imitate in an absurd or comically exaggerated way.Appreciate: to understand the worth or importance of (something or someone).Approve: officially agree to or accept as satisfactory.Annoy: make (someone) a little angry; irritate.

Why the other options are wrong
  • A. To appreciate means to value or recognize the worth or quality of something, which is opposite in meaning to lampoon.
  • C. To approve means to agree with or accept something, which is not related to lampooning.
  • D. To annoy means to irritate or bother someone, which is not related to the meaning of lampoon.

Q22. The thickest chamber of the human heart is:

  • A. Left atrium
  • B. Right atrium
  • C. Right ventricle
  • D. Left ventricle

Explanation: The left ventricle of your heart is larger and thicker than the other chambers. This is because it has to pump the blood further around the body, and against a higher pressure. The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle through the tricuspid valve and hence don't need very thick walls. The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle through the mitral valve, hence it also doesn’t need thick walls.

Why the other options are wrong
  • A. The left atrium receives oxygen- rich blood from the lungs and pumps it to the left ventricle through the mitral valve, hence it also doesn't need thick walls.
  • B. The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle through the tricuspid valve and hence doesn't need very thick walls.
  • C. The right ventricle pumps the oxygen-poor blood to the lungs through the pulmonary valve.

Q23. The enzymes required for the Kreb cycle are found in _.

  • A. F1 particles
  • B. Lysosomes
  • C. Cytoplasm
  • D. Matrix

Explanation: The Krebs cycle enzymes are membrane proteins found within the matrix of the mitochondria except for succinate dehydrogenase which is an integral membrane protein locked to the inner mitochondrial membrane.

Why the other options are wrong
  • A. F1 particles are found in the matrix of mitochondria and is found attached to the cristae. It plays a very important role in the production of ATP molecules as it contains an enzyme called ATPase.
  • B. A lysosome is a membrane- bound cell organelle that contains digestive enzymes.
  • C. The cytoplasm is a thick solution that fills each cell and is enclosed by the cell membrane.

Q24. Coccyx vertebrae are located in:

  • A. Cervical region
  • B. Lumbar region
  • C. Pelvic region
  • D. Thoracic region

Explanation: The coccyx, also known as the tailbone, is a small, triangular bone resembling a shortened tail located at the bottom of the spine in the pelvic region. It is composed of three to five coccygeal vertebrae or spinal bones.The cervical spine is the most superior portion of the vertebral column, lying between the cranium and the thoracic vertebrae. It consists of seven distinct vertebrae.The thoracic spine is the longest region of the spine, and by some measures it is also the most complex. Connecting with the cervical spine above and the lumbar spine below, the thoracic spine runs from the base of the neck down to the abdomen.The thoracic spine has 12 vertebrae stacked on top of each other, labeled from T1 down to T12The lumbar spine (lower back) consists of five vertebrae in the lower part of the spine, between the ribs and the pelvis. The five lumbar vertebrae are numbered L1 to L5

Why the other options are wrong
  • A. The cervical spine is the most superior portion of the vertebral column, lying between the cranium and the thoracic vertebrae. It consists of seven distinct vertebrae.
  • B. The lumbar spine (lower back) consists of five vertebrae in the lower part of the spine, between the ribs and the pelvis. The five lumbar vertebrae are numbered L1 to L5.
  • D. The thoracic spine is the longest region of the spine, and by some measures it is also the most complex. Connecting with the cervical spine above and the lumbar spine below, the thoracic spine runs from the base of the neck down to the abdomen. The thoracic spine has 12 vertebrae stacked on top of each other, labelled from T1 down to T12.

Q25. Cell-mediated immune response is given by:

  • A. T-lymphocytes
  • B. B lymphocytes
  • C. Neutrophils
  • D. Macrophages

Explanation: Cell-mediated immunity is an immune response that does not involve antibodies. Rather, cell-mediated immunity is the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in response to an antigen. Humoral immunity is also called antibody-mediated immunity. With assistance from helper T cells, B cells will differentiate into plasma B cells that can produce antibodies against a specific antigen. The humoral immune system deals with antigens from pathogens that are freely circulating, or outside the infected cells. Antibodies produced by the B cells will bind to antigens, neutralizing them, or causing lysis (dissolution or destruction of cells by a lysin) or phagocytosis.

Why the other options are wrong
  • B. B lymphocytes, or B cells, are a type of white blood cell involved in the immune system. They play a crucial role in the adaptive immune response by producing antibodies, which recognize and neutralize pathogens like bacteria and viruses.
  • C. Neutrophils are a type of white blood cell that forms a significant part of the body's immune system. They are essential for fighting bacterial infections and are often the first responders to sites of infection or inflammation.
  • D. Macrophages are a type of white blood cell that functions as a part of the immune system. They play a key role in engulfing and digesting cellular debris, foreign substances, and pathogens. Macrophages also contribute to the regulation of immune responses and tissue repair.

Q26. Crossing over takes place during _ of meiosis.

  • A. Prophase I
  • B. Telophase I
  • C. Metaphase I
  • D. Anaphase I

Explanation: Meiosis consists of two divisions, both of which follow the same stages as mitosis (prophase, metaphase, anaphase, telophase). Meiosis is preceded by interphase, in which DNA is replicated to produce chromosomes consisting of two sister chromatids. A second growth phase called interkinesis may occur between meiosis I and II, however no DNA replication occurs in this stage: Prophase I: Chromosomes condense, nuclear membrane dissolves, homologous chromosomes form bivalents, crossing over occurs. Metaphase I: Spindle fibres from opposing centrosomes connect to bivalents (at centromeres) and align them along the middle of the cell. Anaphase I: Spindle fibres contract and split the bivalent, homologous chromosomes move to opposite poles of the cell. Telophase I: Chromosomes decondense, nuclear membrane may reform, cell divides (cytokinesis) to form two haploid daughter cells.

Why the other options are wrong
  • B. In Telophase I, chromosomes decondense, nuclear membrane may reform, cell divides (cytokinesis) to form two haploid daughter cells.
  • C. In Metaphase I, spindle fibres from opposing centrosomes connect to bivalents (at centromeres) and align them along the middle of the cell.
  • D. In Anaphase I, spindle fibres contract and split the bivalent, homologous chromosomes move to opposite poles of the cell.

Q27. During breathing, air from pharynx enters to:

  • A. Trachea
  • B. Bronchioles
  • C. Alveoli
  • D. Bronchi

Explanation: When you inhale through your nose or mouth, air travels down your pharynx (back of your throat), passes through your larynx (voice box) and into your trachea (windpipe). Your trachea is divided into two air passages called bronchial tubes. One bronchial tube leads to your left lung, the other to your right lung.

Why the other options are wrong
  • B. Bronchioles are small, narrow air passages in the respiratory system that branch off from the bronchi, which are larger airways in the lungs. The bronchioles are part of the conducting zone of the respiratory system, meaning they function to conduct air to and from the gas exchange surfaces in the lungs.
  • C. Alveoli are tiny, grape-like air sacs located at the end of the bronchioles in the lungs. These structures are the primary sites for the exchange of oxygen and carbon dioxide between the air and the bloodstream. The alveoli are essential for the respiratory system's main function: breathing and gas exchange.
  • D. The bronchi are the two main branches of the trachea (windpipe) that lead into the lungs. These air passages play a crucial role in the respiratory system, facilitating the flow of air to and from the lungs during the process of breathing. The bronchi are part of the larger respiratory airway system and are essential for the distribution of air within the lungs.The trachea bifurcates into two primary bronchi, each entering one of the lungs. These primary bronchi are also known as the main bronchi.

Q28. Gradual breakdown of the alveolar wall leads to which type of disease in a smoker?

  • A. Coronary heart disease
  • B. Bronchitis
  • C. Emphysema
  • D. Asthma

Explanation: In emphysema, the inner walls of the lungs' air sacs (alveoli) are damaged, causing them to eventually rupture. This creates one larger air space instead of many small ones and reduces the surface area available for gas exchange. Emphysema is a lung condition that causes shortness of breath.Asthma is a condition in which your airways narrow and swell and may produce extra mucus. This can make breathing difficult and trigger coughing, a whistling sound (wheezing) when you breathe out and shortness of breath.Bronchitis is an infection of the main airways of the lungs (bronchi), causing them to become irritated and inflamed. The main symptom is a cough, which may bring up yellow-grey mucus (phlegm)Coronary heart disease (CHD), or coronary artery disease, develops when the coronary arteries become too narrow. The coronary arteries are the blood vessels that supply oxygen and blood to the heart.CHD tends to develop when cholesterol builds up on the artery walls, creating plaques. These plaques cause the arteries to narrow, reducing blood flow to the heart. A clot can sometimes obstruct the blood flow, causing serious health problems.

Why the other options are wrong
  • A. Coronary heart disease (CHD), or coronary artery disease, develops when the coronary arteries become too narrow. The coronary arteries are the blood vessels that supply oxygen and blood to the heart.CHD tends to develop when cholesterol builds up on the artery walls, creating plaques. These plaques cause the arteries to narrow, reducing blood flow to the heart. A clot can sometimes obstruct the blood flow, causing serious health problems.
  • B. Bronchitis is an infection of the main airways of the lungs (bronchi), causing them to become irritated and inflamed. The main symptom is a cough, which may bring up yellow-grey mucus (phlegm).
  • D. Asthma is a condition in which your airways narrow and swell and may produce extra mucus. This can make breathing difficult and trigger coughing, a whistling sound (wheezing) when you breathe out and shortness of breath

Q29. Which of the following holds the alpha helix of protein in its place:

  • A. R group
  • B. Disulfide bond
  • C. Amino group
  • D. Hydrogen bond

Explanation: The α-helix is a right-handed helix with the peptide bonds located on the inside and the side chains extending outward. It is stabilized by the regular formation of hydrogen bonds parallel to the axis of the helix; they are formed between the amino and carbonyl groups of every fourth peptide bond

Why the other options are wrong

    Q30. If the molecule can bind to another site of the enzyme rather than the true active site, it is referred to as:

    • A. Competitive inhibitors
    • B. Allosteric inhibition
    • C. Non-competitive inhibitors
    • D. Irreversible inhibition

    Explanation: Non-competitive inhibitors are molecules that bind to an enzyme at a location other than the active site, leading to a conformational change in the enzyme's structure. This conformational change makes the active site less effective at catalyzing the reaction, even though the inhibitor does not directly compete with the substrate for binding to the active site.

    Why the other options are wrong
    • A. A competitive inhibitor is any molecule that can bind to the active site of an enzyme with sufficient affinity such that it can compete with the enzyme's natural substrate and reduce enzyme activity as a result.
    • B. When an inhibitor binds to the enzyme, all the active sites of the protein complex of the enzyme undergo conformational changes so that the activity of the enzyme decreases. In other words, an allosteric inhibitor is a type of molecule which binds to the enzyme specifically at an allosteric site.
    • D. An irreversible inhibitor inactivates an enzyme by bonding covalently to a particular group at the active site. It permanently blocks the action of enzymes.

    Q31. _ is the site of light-independent reaction.

    • A. Thylakoid membrane
    • B. Thylakoid space
    • C. Stroma
    • D. Grana

    Explanation: The light-dependent reactions take place on the thylakoid membranes. The inside of the thylakoid membrane is called the lumen, and outside the thylakoid membrane is the stroma, where the light-independent reactions take place. Thylakoids are arranged in stacks called grana.The chloroplast matrix is called the stroma and contains enzymes that catalyse the light-independent reactions of photosynthesis. But stroma is not the site for light reactions. Stromal lamellae connect two or more grana to each other. In this way, the lamellae act as a skeleton of the chloroplast, maintaining efficient distances between the grana, thereby maximising the overall efficiency of the chloroplast. Dark reaction does not depend directly on the presence of light but is dependent on the products of light reaction i.e., ATP and NADPH. The dark reaction occurs through the Calvin cycle.

    Why the other options are wrong
    • A. It is incorrect.
    • B. It is incorrect.
    • D. It is incorrect.

    Q32. When a nerve impulse jumps from one node of Ranvier to the next in a myelinated neuron, it's called _.

    • A. Synapses
    • B. Saltatory conduction
    • C. Resting potential
    • D. Membrane potential

    Explanation: Saltatory conduction is the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials.

    Why the other options are wrong
    • A. In the central nervous system, a synapse is a small gap at the end of a neuron that allows a signal to pass from one neuron to the next.
    • C. Resting potential is the imbalance of electrical charge that exists between the interior of electrically excitable neurons (nerve cells) and their surroundings.
    • D. Membrane potential (also transmembrane potential or membrane voltage) is the difference in electric potential between the interior and the exterior of a biological cell. Thus,

    Q33. The ability to distinguish between two separate points/objects is:

    • A. Magnification
    • B. Fractionation
    • C. Centrifugation
    • D. Resolution

    Explanation: Scientists think of resolution as the ability to tell that two objects that are very close together are distinct objects rather than just one.Fractionation is a separation process in which a certain quantity of a mixture (gas, solid, liquid, enzymes, suspension, or isotope) is divided during a phase transition, into a number of smaller quantities (fractions) in which the composition varies according to a gradient.Centrifugation is a technique used for the separation of particles from a solution according to their size, shape, density, viscosity of the medium and rotor speed. The particles are suspended in a liquid medium and placed in a centrifuge tube. The tube is then placed in a rotor and spun at a defined speed.Magnification is the process of enlarging the apparent size, not physical size, of something

    Why the other options are wrong
    • A. Magnification is the process of enlarging the apparent size, not physical size, of something.
    • B. Fractionation is a separation process in which a certain quantity of a mixture (gas, solid, liquid, enzymes, suspension, or isotope) is divided during a phase transition, into a number of smaller quantities (fractions) in which the composition varies according to a gradient.
    • C. Centrifugation is a technique used for the separation of particles from a solution according to their size, shape, density, viscosity of the medium and rotor speed. The particles are suspended in a liquid medium and placed in a centrifuge tube. The tube is then placed in a rotor and spun at a defined speed.

    Q34. The term “Loss of appetite” refers to disease:

    • A. Botulism
    • B. Anorexia nervosa
    • C. Obesity
    • D. Bulemia nervosa

    Explanation: Anorexia nervosa is an eating disorder characterized by an abnormally low body weight, an intense fear of gaining weight and a distorted perception of weight.

    Why the other options are wrong
    • A. Botulism is a rare and potentially fatal illness caused by a toxin produced by the bacterium Clostridium botulinum.
    • C. Obesity is a complex disease involving an excessive amount of body fat.
    • D. Bulimia nervosa, commonly called bulimia, is an eating disorder characterised by an obsession for binge(consuming unusually large amounts of food and feel unable to stop eating) eating.

    Q35. They serve as a scaffold for formation of higher order chromatin structure:

    • A. Nucleosome
    • B. Nucleus
    • C. Chromosomes
    • D. Histones

    Explanation: Nucleosomes are the basic packing unit of DNA built from histone proteins around which DNA is coiled. Nucleosomes are connected by short DNA segments (termed 'linker DNA') into nucleosomal arrays, which undergo short-range interactions with neighbouring nucleosomes to form chromatin fibres. Subsequent fibre–fibre interactions contribute to the high degree of compaction observed in the condensed chromosome. They serve as a scaffold for formation of higher order chromatin structure as well as for a layer of regulatory control of gene expressio.

    Why the other options are wrong
    • B. This option is incorrect.
    • C. This option is incorrect.
    • D. This option is incorrect.

    Q36. Salivary Amylase begins to digest Starch to shorter polysaccharides and then to:

    • A. Glucose
    • B. Maltose
    • C. Sucrose
    • D. Lactose

    Explanation: The enzyme salivary amylase breaks starch into smaller polysaccharides and the then maltose. Maltose is converted to two molecules of glucose by the enzyme maltase.Sucrase breaks down sucrose into glucose and fructose. Lactase breaks down lactose (or “milk sugar”) into glucose and galactose.

    Why the other options are wrong
    • C. Sucrase breaks down sucrose into glucose and fructose.
    • D. Lactase breaks down lactose (or "milk sugar") into glucose and galactose.

    Q37. The chemical nature of primers used in the PCR process is _.

    • A. RNA
    • B. Protein
    • C. Carbohydrate
    • D. DNA

    Explanation: Primers are small, chemically synthesised oligonucleotides that are complementary to the sequences, present at 3' end of the template DNA. They hybridise to the target DNA region, one to each strand of the double helix. These primers are oriented with their ends facing each other allowing synthesis of the DNA towards one another. Thus, the primer is a short, single-stranded DNA sequence which hybridises with the template DNA and defines the region of the DNA that needs to be amplified.

    Why the other options are wrong
    • B. Proteins are not used as primers in PCR. Primers need to be nucleic acids to participate in the DNA replication process, and proteins do not have the complementary base-pairing ability required for this function.
    • C. Carbohydrates are not used as primers in PCR. Similar to proteins, carbohydrates lack the nucleotide sequences and base-pairing ability necessary for DNA replication in the PCR process.
    • D. PCR primers are short, single-stranded DNA sequences that are complementary to the target DNA regions flanking the region of interest. They serve as starting points for DNA synthesis by DNA polymerase during the PCR process.

    Q38. In viruses, a combined structure formed by core (Nucleic Acid) and capsid is:

    • A. Nucleocapsid
    • B. Prion
    • C. Envelope
    • D. Capsomeres

    Explanation: The capsid and nucleic acid together are known as the nucleocapsid. A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally. Prion diseases can affect both humans and animals. A viral envelope is the outermost layer of many types of viruses. It protects the genetic material in their life-cycle when traveling between host cells. The capsomere is a subunit of the capsid, an outer covering of protein that protects the genetic material of a virus.

    Why the other options are wrong
    • B. A prion is a type of protein that can trigger normal proteins in the brain to fold abnormally. Prion diseases can affect both humans and animals.
    • C. A viral envelope is the outermost layer of many types of viruses. It protects the genetic material in their life-cycle when travelling between host cells.
    • D. The capsomere is a subunit of the capsid, an outer covering of protein that protects the genetic material of a virus.

    Q39. Skull, vertebral column, ribs, and sternum forms:

    • A. Appendicular skeleton
    • B. Hydrostatic skeleton
    • C. Exoskeleton
    • D. Axial skeleton

    Explanation: The axial skeleton forms a vertical axis that includes the head, neck, back, and chest. It has 80 bones and consists of the skull, vertebral column, and thoracic cage.The appendicular skeleton is the portion of the skeleton of vertebrates consisting of the bones that support the appendages. There are 126 bones. The appendicular skeleton includes the skeletal elements within the limbs, as well as supporting shoulder girdle pectoral and pelvic girdle.A hydrostatic skeleton is a skeleton formed by a fluid-filled compartment within the body, called the coelom.An exoskeleton is an external skeleton that supports and protects an animal's body.

    Why the other options are wrong
    • A. The appendicular skeleton is the portion of the skeleton of vertebrates consisting of the bones that support the appendages. There are 126 bones. The appendicular skeleton includes the skeletal elements within the limbs, as well as supporting shoulder girdle pectoral and pelvic girdle.
    • B. A hydrostatic skeleton is a skeleton formed by a fluid-filled compartment within the body, called the coelom.
    • C. An exoskeleton is an external skeleton that supports and protects an animal's body.

    Q40. Synthesis of microtubules increases in:

    • A. M phase
    • B. S phase
    • C. G1 phase
    • D. G2 phase

    Explanation: Following the G1 is the S-phase (synthesis phase) during which the DNA is synthesised and (chromosome are replicated) which initiates G2 phase (pre- mitotic phase), thus preparing the cell for division e.g., energy storage for chromosome movements, mitosis specific proteins, RNA and microtubule subunits (for spindle fibres) synthesise. G2 phase is the second growth phase. It occurs after the synthesis phase in a typical cell cycle. In the G2 phase synthesis of tubulin protein which is the major component of microtubules takes place. The spindle fibres are made of microtubules.

    Why the other options are wrong
    • A. It is mitotic phase and is not related to synthesis of microtubules.
    • B. It is related to DNA synthesis and chromosome replication.
    • C. G1 (Gap 1) is the period of extensive metabolic activity, in which cell normally grows in size, speciic enzymes, are synthesized and DNA base units are accumulated for the DNA synthesis.

    Q41. The region of the chromosome or, more specifically, the length of the DNA molecule, which has a particular function is called _.

    • A. Kinetochore
    • B. Locus
    • C. Allele
    • D. Gene

    Explanation: The gene is the basic physical and functional unit of heredity. It consists of a specific sequence of nucleotides at a given position on a given chromosome that codes for a specific protein.In genetics, a locus is a specific, fixed position on a chromosome where a particular gene or genetic marker is located.

    Why the other options are wrong
    • A. A kinetochore is a disc-shaped protein structure associated with duplicated chromatids in eukaryotic cells where the spindle fibres attach during cell division to pull sister chromatids apart.
    • B. In genetics, a locus is a specific, fixed position on a chromosome where a particular gene or genetic marker is located. Option C: An allele is one of two, or more, forms of a given gene variant.
    • C. It is incorrect.

    Q42. Urea cycle helps in the the detoxification of:

    • A. Creatine
    • B. Amino acids
    • C. Carbon dioxide
    • D. Ammonia

    Explanation: The urea cycle is the final pathway for removal of surplus nitrogen from the body, and the major route in humans for detoxification of ammonia. The full complement of enzymes is expressed only in the liver. Inherited deficiencies of urea cycle enzymes lead to hyperammonemia, which causes brain damage.

    Why the other options are wrong
    • A. Creatine is a nitrogenous organic compound that plays a role in energy metabolism, particularly in the muscles. It is not directly involved in the detoxification of ammonia or any other waste products
    • B. While the breakdown of amino acids can produce ammonia as a byproduct, the primary purpose of the urea cycle is to specifically detoxify and eliminate ammonia from the body.
    • C. It is incorrect in the context of the urea cycle and detoxification. Carbon dioxide is not directly detoxified by the urea cycle.

    Q43. Chitin which makes the exoskeleton in insects is further hardened by:

    • A. Protein and Sodium Bicarbonate
    • B. Protein and Calcium Carbonate
    • C. Protein and Potassium Carbonate
    • D. Protein and Sodium Carbonate

    Explanation: Chitin is translucent and tough in its pure form, but it also combines with other materials to form a strong outer structure. For example, in arthropods, it combines with proteins while in crustaceans, it combines with calcium carbonate. This material makes the exoskeleton and shells hard, tough, and stiff.

    Why the other options are wrong
    • A. Chitin is translucent and tough in its pure form, but it also combines with other materials to form a strong outer structure. For example, in arthropods, it combines with proteins while in crustaceans, it combines with calcium carbonate. This material makes the exoskeleton and shells hard, tough, and stiff.
    • C. Chitin is translucent and tough in its pure form, but it also combines with other materials to form a strong outer structure. For example, in arthropods, it combines with proteins while in crustaceans, it combines with calcium carbonate. This material makes the exoskeleton and shells hard, tough, and stiff.
    • D. Chitin is translucent and tough in its pure form, but it also combines with other materials to form a strong outer structure. For example, in arthropods, it combines with proteins while in crustaceans, it combines with calcium carbonate. This material makes the exoskeleton and shells hard, tough, and stiff.

    Q44. Number of salivary glands found in the human oral cavity.

    • A. 4
    • B. 3
    • C. 6
    • D. 2

    Explanation: Humans have three paired major salivary glands (parotid, submandibular, and sublingual) which are 6 in total.

    Why the other options are wrong

      Q45. Following group is the example of acoelomates:

      • A. Annelids
      • B. Aschelminthes
      • C. Molluscs
      • D. Platyhelminthes

      Explanation: Acoelomates do not possess a body cavity or coelom i.e the fluid-filled cavity between the digestive tract and the body wall that also surrounds the other internal organs is absent. Platyhelminthes and sponges are classic examples of acoelomates. In some animals, the embryonic blastocoel acts as a fluid-filled cavity. This body cavity is partially lined with the mesodermal derivative cells. Here, the coelom is much reduced or lost. It is not considered a true coelom, and hence the name pseudocoelomates. Examples include nematodes (roundworms). Animals that have their body cavities filled with fluid are called coelomates. Their internal organs are suspended in the fluid cavity. Examples include arthropods, annelids, molluscs, hemichordates, echinoderms and chordates.

      Why the other options are wrong
      • A. Acoelomates do not possess a body cavity or coelom i.e the fluid-filled cavity between the digestive tract and the body wall that also surrounds the other internal organs is absent. Platyhelminthes and sponges are classic examples of acoelomates. In some animals, the embryonic blastocoel acts as a fluid-filled cavity. This body cavity is partially lined with the mesodermal derivative cells. Here, the coelom is much reduced or lost. It is not considered a true coelom, and hence the name pseudocoelomates. Examples include nematodes (roundworms). Animals that have their body cavities filled with fluid are called coelomates. Their internal organs are suspended in the fluid cavity. Examples include arthropods, annelids, molluscs, hemichordates, echinoderms and chordates.
      • B. Acoelomates do not possess a body cavity or coelom i.e the fluid-filled cavity between the digestive tract and the body wall that also surrounds the other internal organs is absent. Platyhelminthes and sponges are classic examples of acoelomates. In some animals, the embryonic blastocoel acts as a fluid-filled cavity. This body cavity is partially lined with the mesodermal derivative cells. Here, the coelom is much reduced or lost. It is not considered a true coelom, and hence the name pseudocoelomates. Examples include nematodes (roundworms). Animals that have their body cavities filled with fluid are called coelomates. Their internal organs are suspended in the fluid cavity. Examples include arthropods, annelids, molluscs, hemichordates, echinoderms and chordates.
      • C. Acoelomates do not possess a body cavity or coelom i.e the fluid-filled cavity between the digestive tract and the body wall that also surrounds the other internal organs is absent. Platyhelminthes and sponges are classic examples of acoelomates. In some animals, the embryonic blastocoel acts as a fluid-filled cavity. This body cavity is partially lined with the mesodermal derivative cells. Here, the coelom is much reduced or lost. It is not considered a true coelom, and hence the name pseudocoelomates. Examples include nematodes (roundworms). Animals that have their body cavities filled with fluid are called coelomates. Their internal organs are suspended in the fluid cavity. Examples include arthropods, annelids, molluscs, hemichordates, echinoderms and chordates.

      Q46. Glycosidic bond is formed by the:

      • A. Removal of Oxygen
      • B. Addition of Oxygen
      • C. Removal of water
      • D. Addition of water

      Explanation: Glycosidic bond is a condensation reaction between two sugar units, where the H- group from one sugar interacts with the -OH group on another to release water and link the sugar units together to form a polysaccharide.

      Why the other options are wrong

        Q47. Which of the following statements is correct about the respiratory pigments?

        • A. Myoglobin and Haemoglobin has higher affinity for nitrogen
        • B. Cyanide and Haemoglobin has a low affinity for oxygen
        • C. Myoglobin has more affinity for oxygen as compared to haemoglobin
        • D. Albumin, Globulin and Globin proteins are present in respiratory pigments

        Explanation: Myoglobin's affinity for oxygen is higher than haemoglobin. And unlike haemoglobin which is found in the red blood cells, myoglobin is found in muscle tissues. Thus, haemoglobin's lower affinity for oxygen serves it well because it allows haemoglobin to release oxygen more easily in the cells. Myoglobin, on the other hand, has a significantly higher affinity for oxygen and will therefore be much less inclined to release it once it is bound.

        Why the other options are wrong
        • A. Both myoglobin and hemoglobin have a higher affinity for oxygen than for nitrogen. Myoglobin and hemoglobin are proteins that play crucial roles in the transport and storage of oxygen in the body. Hence, this option is incorrect.
        • B. Cyanide is a highly toxic compound that can interfere with cellular respiration, leading to a rapid and severe lack of oxygen in the body. It acts by inhibiting cytochrome c oxidase, a critical enzyme in the electron transport chain of cellular respiration. This disruption prevents cells from utilizing oxygen, despite its availability in the bloodstream. However, the interaction of cyanide with hemoglobin is indirect. Cyanide primarily affects the cells at the mitochondrial level rather than directly interacting with hemoglobin. Hemoglobin's function is to bind and transport oxygen, and under normal conditions, it does not have low affinity for oxygen.
        • D. Respiratory pigments are proteins that play a crucial role in transporting gases, such as oxygen and carbon dioxide, in the blood. However, the proteins albumin, globulin, and globin are not typically considered respiratory pigments. Hence, this option is incorrect.

        Q48. Conversion of ammonium into nitrates is:

        • A. Nitrification
        • B. Nitrogen Fixation
        • C. Ammonification
        • D. Denitrification

        Explanation: Nitrosomonas convert ammonia into nitrates by a process called nitrification. Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia. Ammonification refers to any chemical reaction in which NH2 groups are converted into ammonia or its ionic form, ammonium (NH4+), as an end product. Denitrification is the microbial process of reducing nitrate and nitrite to gaseous forms of nitrogen, principally nitrous oxide (N2O) and nitrogen (N2).

        Why the other options are wrong
        • B. Nitrogen fixation is a process by which molecular nitrogen in the air is converted into ammonia.
        • C. Ammonification refers to any chemical reaction in which NH2 groups are converted into ammonia or its ionic form, ammonium (NH4+), as an end product.
        • D. Nitrates are also lost as a result of the activities of certain soil bacteria; in the absence of oxygen these bacteria break down nitrates releasing nitrogen back into the atmosphere and using the oxygen for their own respiration. This process is known as denitrification.

        Q49. An area previously supporting life is made barren, the subsequent recolonization is called _.

        • A. Climax community
        • B. Pioneer succession
        • C. Primary succession
        • D. Secondary succession

        Explanation: Secondary succession occurs when the primary ecosystem gets destroyed. For example, a climax community gets destroyed by fire. It gets recolonized after the destruction. A climax community is the final stage of succession, remaining relatively unchanged until destroyed by an event such as fire or human interference. Primary succession is an ecological succession that begins in essentially lifeless areas, such as regions in which there is no soil or where the soil is incapable of sustaining life The pioneer species are hardy species that are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by fire. Therefore, the correct answer is secondary succession.

        Why the other options are wrong
        • A. A climax community is the final stage of succession, remaining relatively unchanged until destroyed by an event such as fire or human interference.
        • B. Pioneer succession: The first organisms appearing in the regions of primary succession are pioneer species (usually lichens or mosses). They are the first species present. They must be strong and hardy. The development of a new community is succession.
        • C. Primary succession is an ecological succession that begins in essentially lifeless areas, such as regions in which there is no soil or where the soil is incapable of sustaining life.

        Q50. In human female, the egg is fertilized in:

        • A. Ovary
        • B. Vagina
        • C. Oviduct
        • D. Uterus

        Explanation: In human females, fertilization typically occurs in the fallopian tubes, also known as the oviducts. The process begins with the release of an egg (ovum) from one of the ovaries during ovulation. The released egg then travels through the fallopian tube. If sexual intercourse has taken place and sperm are present in the female reproductive tract, fertilization can occur in the fallopian tube.

        Why the other options are wrong
        • A. In human females, fertilization typically occurs in the fallopian tubes, also known as the oviducts. The process begins with the release of an egg (ovum) from one of the ovaries during ovulation. The released egg then travels through the fallopian tube. If sexual intercourse has taken place and sperm are present in the female reproductive tract, fertilization can occur in the fallopian tube.
        • B. In human females, fertilization typically occurs in the fallopian tubes, also known as the oviducts. The process begins with the release of an egg (ovum) from one of the ovaries during ovulation. The released egg then travels through the fallopian tube. If sexual intercourse has taken place and sperm are present in the female reproductive tract, fertilization can occur in the fallopian tube.
        • D. In human females, fertilization typically occurs in the fallopian tubes, also known as the oviducts. The process begins with the release of an egg (ovum) from one of the ovaries during ovulation. The released egg then travels through the fallopian tube. If sexual intercourse has taken place and sperm are present in the female reproductive tract, fertilization can occur in the fallopian tube.

        Q51. Which hormone is released in females in response to FSH from the pituitary gland?

        • A. Estrogen
        • B. ADH
        • C. Oxytocin
        • D. Progesterone

        Explanation: Follicle-stimulating hormone (FSH) from the pituitary gland stimulates the ovaries in females. In response to FSH, the ovaries produce estrogen. Estrogen is a group of hormones that includes estradiol, estrone, and estriol. These hormones play crucial roles in the development and maturation of the ovarian follicles (structures that contain the developing eggs) and in regulating the menstrual cycle.

        Why the other options are wrong
        • B. Follicle-stimulating hormone (FSH) from the pituitary gland stimulates the ovaries in females. In response to FSH, the ovaries produce estrogen. Estrogen is a group of hormones that includes estradiol, estrone, and estriol. These hormones play crucial roles in the development and maturation of the ovarian follicles (structures that contain the developing eggs) and in regulating the menstrual cycle.
        • C. Follicle-stimulating hormone (FSH) from the pituitary gland stimulates the ovaries in females. In response to FSH, the ovaries produce estrogen. Estrogen is a group of hormones that includes estradiol, estrone, and estriol. These hormones play crucial roles in the development and maturation of the ovarian follicles (structures that contain the developing eggs) and in regulating the menstrual cycle.
        • D. Follicle-stimulating hormone (FSH) from the pituitary gland stimulates the ovaries in females. In response to FSH, the ovaries produce estrogen. Estrogen is a group of hormones that includes estradiol, estrone, and estriol. These hormones play crucial roles in the development and maturation of the ovarian follicles (structures that contain the developing eggs) and in regulating the menstrual cycle.

        Q52. In cross-section each centriole consists of nine (each in triplets) of:

        • A. Microfilaments
        • B. Microvilli
        • C. Microtubules
        • D. Intermediate filaments

        Explanation: Typical centrioles are made of 9 triplets of microtubules organized with radial symmetry.

        Why the other options are wrong
        • A. Microfilaments, also called actin filaments, are polymers of the protein actin that are part of a cell's cytoskeleton.
        • B. Microvilli are microscopic cellular membrane protrusions that increase the surface area for diffusion and minimise any increase in volume, and are involved in a wide variety of functions.
        • D. Intermediate filaments are important components of the cell's cytoskeletal system. They may stabilise organelles, like the nucleus, or they may be involved in specialised junctions. They are distinguished from "thin filaments" by their size (8-10 nm) and the fact that thin filaments are motile.

        Q53. In immunoglobulins / antibodies, Two light chains and two heavy chains are linked to each other by:

        • A. Covalent bonds
        • B. Hydrogen bonds
        • C. Ionic bonds
        • D. Disulphide bonds

        Explanation: Each antibody is made up of two short light (L) peptide chains and two long heavy (H) peptide chains (H2L2) joined to each other by disulfide bonds. Disulfide bonds are covalent linkages between the sulphur-containing side chains of cysteine amino acids.The peptide chains are arranged in a Y shaped structure. Each chain in the antibody has both constant and variable regions. The amino acid sequence and conformation of the variable region keeps changing from one type of antibody to the other. The conformation and amino acid sequence of the constant region remains the same. The unique antigen binding site in each antibody that is compatible with specific antigens is composed of the variable regions of both the heavy and the light chains.

        Why the other options are wrong
        • A. This is incorrect.
        • B. This is incorrect.
        • C. This is incorrect.

        Q54. In the nervous system chemical messengers are called _.

        • A. Neurotransmitters
        • B. Hormones
        • C. CHemoreceptors
        • D. Enzymes

        Explanation: Neurotransmitters are often referred to as the body's chemical messengers. They are the molecules used by the nervous system to transmit messages between neurons, or from neurons to muscles.

        Why the other options are wrong
        • B. Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work slowly, over time, and affect many different processes, including: Growth and development
        • C. Chemoreceptors are special nerve cells that detect changes in the chemical composition of the blood and send information to the brain to regulate cardiovascular and respiratory functions. There are two major types, which are peripheral and central chemoreceptors.
        • D. Enzymes are proteins that help speed up chemical reactions in our bodies i.e; biological catalysts.

        Q55. The first part of the large intestine is:

        • A. Colon
        • B. Appendix
        • C. Caecum
        • D. Rectum

        Explanation: The large intestine has four parts: cecum, colon, rectum, and anal canal. Partly digested food moves through the cecum into the colon, where water and some nutrients and electrolytes are removed. The remaining material, solid waste called stool, moves through the colon, is stored in the rectum, and leaves the body through the anal canal and anus. The appendix is a small, tube-like structure attached to the first part of the large intestine.

        Why the other options are wrong
        • A. Colon is right next to ceacum in large intestine which is the first part of large intestine.
        • B. Appendix is a small finger-like projection arising from the blind end of ceacum.
        • D. Rectum is the last part of large intestine which stores the feaces temporarily.

        Q56. Scapula is a:

        • A. Tail bone
        • B. Hip bone
        • C. Skull bone
        • D. Shoulder bone

        Explanation: The scapula or shoulder blade is the bone that connects the clavicle to the humerus. The scapula forms the posterior of the shoulder girdle. It is a sturdy, flat, triangular bone. The scapula provides attachment to several groups of muscles.

        Why the other options are wrong
        • A. The tailbone, scientifically known as the coccyx, is a small, triangular bone at the base of the spine. It consists of three to five fused vertebrae and is situated just above the cleft of the buttocks. The coccyx serves as an attachment point for various muscles, ligaments, and tendons. While it doesn't have a major role in weight-bearing or movement, it plays a part in supporting the pelvic floor and provides attachment points for muscles involved in posture and movement of the lower back and pelvis.
        • B. The hip bone is a large, flat bone forming part of the pelvis. It consists of three fused bones: the ilium, ischium, and pubis. Together, they create the socket for the hip joint and contribute to the structure of the pelvis, providing support for the body and attachment points for muscles.
        • C. The skull is the bony structure that encloses and protects the brain. It consists of two main parts: the cranium, which houses the brain, and the mandible (lower jaw), which is involved in chewing and speech. The skull also protects and supports sensory organs, such as the eyes and ears.

        Q57. A complete turn of the double helix of DNA comprises of:

        • A. 34 nanometer
        • B. 3.4 Angstrom
        • C. 3.4 nanometer
        • D. 34 micrometers

        Explanation: At a distance of 3.4nm, the double helix DNA produces one full turn. Each full turn of DNA consists of 10 base pairs. Pitch is the term for the distance covered by a DNA molecule in one full turn.

        Why the other options are wrong
        • A. At a distance of 3.4nm, the double helix DNA produces one full turn. Each full turn of DNA consists of 10 base pairs. Pitch is the term for the distance covered by a DNA molecule in one full turn.
        • B. At a distance of 3.4nm, the double helix DNA produces one full turn. Each full turn of DNA consists of 10 base pairs. Pitch is the term for the distance covered by a DNA molecule in one full turn.
        • D. At a distance of 3.4nm, the double helix DNA produces one full turn. Each full turn of DNA consists of 10 base pairs. Pitch is the term for the distance covered by a DNA molecule in one full turn.

        Q58. The enzymes required in Glycolysis are present in:

        • A. Golgi Apparatus
        • B. Cell cytoplasm
        • C. Inner Mitochondrial Membrane
        • D. Matrix of Mitochondria

        Explanation: Glycolysis is the process where glucose breaks partially to form pyruvic acid. Further the pyruvic acid enters as a substrate to continue the respiratory pathway. It takes place in the cytoplasm.It does not depend upon the availability of the oxygen.

        Why the other options are wrong
        • A. It is incorrect as glycolysis is the process where glucose breaks partially to form pyruvic acid. Further the pyruvic acid enters as a substrate to continue the respiratory pathway. It takes place in the cytoplasm.It does not depend upon the availability of the oxygen.
        • C. It is incorrect as glycolysis is the process where glucose breaks partially to form pyruvic acid. Further the pyruvic acid enters as a substrate to continue the respiratory pathway. It takes place in the cytoplasm.It does not depend upon the availability of the oxygen.
        • D. It is incorrect as glycolysis is the process where glucose breaks partially to form pyruvic acid. Further the pyruvic acid enters as a substrate to continue the respiratory pathway. It takes place in the cytoplasm.It does not depend upon the availability of the oxygen.

        Q59. Which lipid is hydrophilic and soluble?

        • A. Triglycerides
        • B. Phospholipids
        • C. Waxes
        • D. Terpenoids

        Explanation: Phospholipids are soluble in both water and oil (amphiphilic) because the hydrocarbon tails of two fatty acids are still hydrophobic, but the phosphate group end is hydrophilic. Phospholipids are the major component of cell membrane to form lipid bilayers.

        Why the other options are wrong
        • A. Triglycerides have 3 fatty acids and glycerin, they are hydrophobic.
        • C. Waxes are similar to fats except that waxes are composed of only one long-chain fatty acid bonded to a long-chain alcohol group attached. Because of their long, nonpolar carbon chains, waxes are extremely hydrophobic (meaning they lack an affinity for water).
        • D. In general, most of the terpenes are highly hydrophobic and insoluble in water but soluble in ethanol, chloroform and diethyl ether.

        Q60. _ hormone is released from the posterior lobe of the pituitary gland.

        • A. Adrenaline
        • B. Thyroid stimulating hormone
        • C. FSH
        • D. Antidiuretic hormone

        Explanation: The posterior lobe of the pituitary gland produces two hormones, vasopressin (Antidiuretic hormone) and oxytocin.Adrenaline is released from the adrenal glands and its major action, together with noradrenaline, is to prepare the body for 'fight or flight'.Thyroid-stimulating hormone, also known as TSH, is a glycoprotein hormone produced by the anterior pituitary.Follicle-stimulating hormone (FSH) is released by the anterior lobe of pituitary gland.

        Why the other options are wrong
        • A. Adrenaline is released from the adrenal glands and its major action, together with noradrenaline, is to prepare the body for 'fight or flight'.
        • B. Thyroid-stimulating hormone, also known as TSH, is a glycoprotein hormone produced by the anterior pituitary.
        • C. Follicle-stimulating hormone (FSH) is released by the anterior lobe of the pituitary gland.

        Q61. Ribosomes are made up of _ and _.

        • A. Proteins and carbohydrates
        • B. RNA and lipid
        • C. RNA and proteins
        • D. RNA and carbohydrates

        Explanation: A ribosome is an intercellular structure made up of equal amounts of both RNA and protein, hence named as 'ribonucleo-protein particles 'and it is the site of protein synthesis in the cell. The ribosome reads the messenger RNA (mRNA) sequence and translates that genetic code into a specified string of amino acids, which grow into long chains that fold to form proteins.

        Why the other options are wrong
        • A. A ribosome is an intercellular structure made up of equal amounts of both RNA and protein, hence named as 'ribonucleo-protein particles 'and it is the site of protein synthesis in the cell.
        • B. A ribosome is an intercellular structure made up of equal amounts of both RNA and protein, hence named as 'ribonucleo-protein particles 'and it is the site of protein synthesis in the cell.
        • D. A ribosome is an intercellular structure made up of equal amounts of both RNA and protein, hence named as 'ribonucleo-protein particles 'and it is the site of protein synthesis in the cell.

        Q62. A non-protein part which is essential for proper functioning of enzyme is called:

        • A. Additional factor
        • B. Cofactor
        • C. Efficient cofactor
        • D. Extra factor

        Explanation: A non-protein part that is essential for the proper functioning of an enzyme is called a "cofactor." Cofactors are often inorganic ions or organic molecules that associate with the protein component (apoenzyme) of an enzyme to form the complete and catalytically active holoenzyme.

        Why the other options are wrong
        • A. In enzymology, enzymes can sometimes have multiple cofactors or coenzymes that contribute to their catalytic activity. These additional cofactors may play specific roles in the enzyme's mechanism or may be involved in modulating its activity under different conditions.
        • C. In enzymology, the efficiency factor may refer to the catalytic efficiency of an enzyme, often quantified by parameters such as the turnover number (kcat) or Michaelis constant (Km).
        • D. A non-protein part that is essential for the proper functioning of an enzyme is called a "cofactor." Cofactors are often inorganic ions or organic molecules that associate with the protein component (apoenzyme) of an enzyme to form the complete and catalytically active holoenzyme.

        Q63. DNA made by joining pieces from two or more different sources is called:

        • A. Probes
        • B. Restriction endonuclease
        • C. Mutated DNA
        • D. Recombinant DNA

        Explanation: Recombinant DNA (or rDNA) is made by combining DNA from two or more sources.DNA probes are stretches of single-stranded DNA used to detect the presence of complementary nucleic acid sequences (target sequences) by hybridization.A restriction enzyme, restriction endonuclease, or restrictase is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites.A mutation is a change in a DNA sequence. Mutations can result from DNA copying mistakes made during cell division, exposure to ionizing radiation, exposure to chemicals called mutagens, or infection by viruses.

        Why the other options are wrong
        • A. Probes are a single-stranded sequence of DNA or RNA that is used to identify specific sequences of DNA or RNA. They are designed as complementary to the part of the genome of interest so that when the probe and the genome are brought together, the probe will hybridize with the target sequence.
        • B. A restriction enzyme, restriction endonuclease, REase, ENase, or restrictase is an enzyme that cleaves DNA into fragments at or near specific recognition sites within molecules known as restriction sites. Restriction enzymes are one class of the broader endonuclease group of enzymes.
        • C. A gene variant is a permanent change in the DNA sequence that makes up a gene. This type of genetic change used to be known as a gene mutation, but because changes in DNA do not always cause disease, it is thought that gene variant is a more accurate term.

        Q64. The hormone which controls the uptake of Sodium ions in kidney and its maintenance in blood plasma is:

        • A. Somatotrophic Hormone
        • B. Aldosterone Hormone
        • C. Gonadotrophic Hormone
        • D. Thyroxine Hormone

        Explanation: Aldosterone is a steroid hormone. Its main role is to regulate salt and water in the body, thus having an effect on blood pressure.Growth hormone (GH), also called somatotropin or human growth hormone, is a peptide hormone secreted by the anterior lobe of the pituitary gland. It stimulates the growth of essentially all tissues of the body, including bone.Gonadotropins: Luteinizing and Follicle Stimulating Hormones. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are called gonadotropins because they stimulate the gonads - in males, the testes, and in females, the ovaries.Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones.

        Why the other options are wrong
        • A. Growth hormone (GH), also called somatotropin or human growth hormone, is a peptide hormone secreted by the anterior lobe of the pituitary gland. It stimulates the growth of essentially all tissues of the body, including bone.
        • C. Gonadotropins: Luteinizing and Follicle Stimulating Hormones. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are called gonadotropins because they stimulate the gonads - in males, the testes, and in females, the ovaries.
        • D. Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones.

        Q65. A. ATP synthesis is seen in bothB. Outer membrane has more surface area in bothC. Circular naked DNA, RNA and 70 ribosomes are seen in bothD. Oxidative phosphorylation occurs in both Which of the following statements are true for mitochondria and chloroplasts?

        • A. A and B
        • B. B and C
        • C. A and C
        • D. A and D

        Explanation: ATP synthesis is seen in both chloroplasts and mitochondria. The inner membrane of mitochondria is folded to increase surface area. Both mitochondria and chloroplasts have small, circular DNA, all kinds of RNA and 70S ribosomes. Oxidative phosphorylation takes place only in mitochondria.

        Why the other options are wrong
        • A. The inner membrane of mitochondria is folded to increase surface area.
        • B. The inner membrane of mitochondria is folded to increase surface area.
        • D. Oxidative phosphorylation takes place only in mitochondria.

        Q66. The capillaries of glomerulus rejoin to form an _.

        • A. Efferent arteriole
        • B. Afferent arteriole
        • C. Peritubular capillaries
        • D. Collecting duct

        Explanation: At the distal end of the glomerulus, the capillaries rejoin to form the afferent arteriole through which blood leaves the glomerulus.The afferent arterioles branch from the renal artery, which supplies blood to the kidneys. The afferent arterioles later diverge into the capillaries of the glomerulus.In the renal system, peritubular capillaries are tiny blood vessels, supplied by the efferent arteriole, that travel alongside nephrons allowing reabsorption and secretion between blood and the inner lumen of the nephron.The collecting duct system of the kidney consists of a series of tubules and ducts that physically connect nephrons to a minor calyx or directly to the renal pelvis.

        Why the other options are wrong
        • B. Afferent arterioles have two functions: they serve to connect the renal artery to the glomerular capillaries and they take an active role in controlling not only the local blood pressure inside the kidney but also your overall body's blood pressure.
        • C. Peritubular capillaries are tiny blood vessels in your kidneys. They filter waste from your blood so the waste can leave your body through urine. Peritubular capillaries also reabsorb nutrients your body needs to work properly, such as minerals.
        • D. The last part of a long, twisting tube that collects urine from the nephrons (cellular structures in the kidney that filter blood and form urine) and moves it into the renal pelvis and ureters. Also called renal collecting tubule.

        Q67. How many sodium ions are pumped out in response to two potassium ions transported into the membrane?

        • A. 4
        • B. 1
        • C. 2
        • D. 3

        Explanation: The sodium-potassium pump actively expels three sodium ions out of the cell while simultaneously transporting two potassium ions into the cell, facilitating the maintenance of proper ion gradients and contributing to the cell's overall electrochemical stability.

        Why the other options are wrong
        • A. This option is incorrect because the sodium-potassium pump transports three sodium ions out of the cell for every two potassium ions transported into the cell, maintaining the proper ionic balance and contributing to the cell's resting membrane potential.
        • B. This option is incorrect as the sodium-potassium pump actively transports three sodium ions out of the cell in exchange for two potassium ions transported into the cell, playing a crucial role in maintaining the electrochemical gradient necessary for various cellular processes, including nerve transmission.
        • C. This choice is inaccurate since the sodium-potassium pump moves three sodium ions out of the cell and transports two potassium ions into the cell, ensuring the appropriate ion concentrations across the cell membrane and supporting essential functions like muscle contraction and nerve impulse transmission.

        Q68. Chance of a crossing over between two loci is directly proportional to their:

        • A. Thickening
        • B. Width
        • C. Length
        • D. Distance

        Explanation: The probability of a crossover between two genes is proportional to the distance between the two genes. That is, the greater the distance between the two genes, the greater the probability that a crossover will occur between them during meiosis.

        Why the other options are wrong
        • A. The probability of a crossover between two genes is proportional to the distance between the two genes. That is, the greater the distance between the two genes, the greater the probability that a crossover will occur between them during meiosis.
        • B. The probability of a crossover between two genes is proportional to the distance between the two genes. That is, the greater the distance between the two genes, the greater the probability that a crossover will occur between them during meiosis.
        • C. The probability of a crossover between two genes is proportional to the distance between the two genes. That is, the greater the distance between the two genes, the greater the probability that a crossover will occur between them during meiosis.

        Q69. Process ensuring the survival of species over long periods of time, even though individual members of the species die.

        • A. Reproduction
        • B. Adaptability
        • C. Mitosis
        • D. Respiration

        Explanation: Reproduction is the biological process by which new individual organisms offspring are produced from their parents. Reproduction is the biological process by which new individual organisms are produced from preexisting ones. It is a fundamental characteristic of living organisms and is essential for the continuation of a species. Reproduction can occur through various mechanisms, and it is central to the life cycle of organisms.

        Why the other options are wrong
        • B. Adaptability means being able to rapidly learn new skills and behaviours in response to changing circumstances.
        • C. Mitosis is a process where a single cell divides into two identical daughter cells.
        • D. Respiration is a chemical reaction that happens in all living cells, including plant cells and animal cells. It is the way that energy is released from glucose so that all the other chemical processes needed for life can happen.

        Q70. Phages which show lysogenic cycle are known as:

        • A. Enveloped Phage
        • B. Virulent Phage
        • C. Temperate phages
        • D. Bacteriophage

        Explanation: Temperate phages are some bacteriophages which display a lysogenic life cycle. Lysogeny is characterized by an integration of the bacteriophage nucleic acid into the host bacteria genome and becomes prophage. In this condition, the bacterium continues to live and reproduce normally. Bacteriophages that only use the lytic cycle are called virulent phages. So, the correct answer is 'temperate phages'.

        Why the other options are wrong
        • A. There is no such term used in biology but it may refer to enveloped viruses.As it is a combined term used for more than .
        • B. The phage which causes lysis of the host cell is known as lytic or virulent phage.
        • D. Viruses that infect bacteria are called bacteriophages.

        Q71. Organs specialized to perform different functions but structurally alike are:

        • A. Analogous organs
        • B. Homologous organs
        • C. Autologous organs
        • D. Anuclogous organs

        Explanation: Organs that have the same internal structure but perform different functions are called homologous organs. Analogous organs are the opposite of homologous organs, which have similar functions but different origins.

        Why the other options are wrong
        • A. The organs which have similar functions but are different in anatomical structures are called analogous organs. Examples of analogous organs are as follows: Wings of an insect and bird. Pectoral fins of sharks and flippers of dolphins.
        • C. Autologous: Auto means self. The stem cells in autologous transplants come from the same person who will get the transplant, so the patient is their own donor.
        • D. There is no term as anuclogous organs

        Q72. By PCR we mean:

        • A. Polymerase chronic reaction
        • B. Polymerase chain reaction
        • C. Polymerase copy reaction
        • D. Polymerase cross-reaction

        Explanation: Polymerase chain reaction (abbreviated PCR) is a laboratory technique for rapidly producing (amplifying) millions to billions of copies of a specific segment of DNA, which can then be studied in greater detail.

        Why the other options are wrong
        • A. This is not the correct expansion. The correct term is "Polymerase Chain Reaction."
        • C. This is not the correct expansion. PCR stands for Polymerase Chain Reaction, not Polymerase Copy Reaction.
        • D. This is not the correct expansion. PCR specifically refers to the Polymerase Chain Reaction and does not involve cross-reactions in its standard usage.

        Q73. If lipopolysaccharides did not appear in the wall of bacteria on staining then it will be known as _.

        • A. Gram-negative
        • B. Gram-positive
        • C. Capsule
        • D. Both Gram positive & negative

        Explanation: The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with. Alternatively, Gram negative bacteria stain pink, which is attributed to a thinner peptidoglycan wall, which does not retain the crystal violet during the decoloring process. Gram-positive bacteria do not contain lipopolysaccharides, but carry surface teichoic acids, lipoteichoic acids and peptidoglycan instead. The outer membrane of Gram-negative bacteria contains lipopolysaccharides, proteins, and phospholipids. The bacterial capsule is a large structure of many bacteria. It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell.

        Why the other options are wrong
        • A. The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with. Alternatively, Gram negative bacteria stain pink, which is attributed to a thinner peptidoglycan wall, which does not retain the crystal violet during the decoloring process. Gram-positive bacteria do not contain lipopolysaccharides, but carry surface teichoic acids, lipoteichoic acids and peptidoglycan instead. The outer membrane of Gram-negative bacteria contains lipopolysaccharides, proteins, and phospholipids. The bacterial capsule is a large structure of many bacteria. It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell.
        • C. The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with. Alternatively, Gram negative bacteria stain pink, which is attributed to a thinner peptidoglycan wall, which does not retain the crystal violet during the decoloring process. Gram-positive bacteria do not contain lipopolysaccharides, but carry surface teichoic acids, lipoteichoic acids and peptidoglycan instead. The outer membrane of Gram-negative bacteria contains lipopolysaccharides, proteins, and phospholipids. The bacterial capsule is a large structure of many bacteria. It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell.
        • D. The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet. Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with. Alternatively, Gram negative bacteria stain pink, which is attributed to a thinner peptidoglycan wall, which does not retain the crystal violet during the decoloring process. Gram-positive bacteria do not contain lipopolysaccharides, but carry surface teichoic acids, lipoteichoic acids and peptidoglycan instead. The outer membrane of Gram-negative bacteria contains lipopolysaccharides, proteins, and phospholipids. The bacterial capsule is a large structure of many bacteria. It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell.

        Q74. The low levels of surfactant produced by alveolar epithelium causes:

        • A. Emphysema
        • B. Respiratory distress syndrome
        • C. Bronchitis
        • D. Asthma

        Explanation: Respiratory distress syndrome (RDS) occurs primarily in premature infants who have not yet produced enough surfactant in their lungs. As a result, their lungs have higher surface tension, making it difficult for them to expand and fill with air properly. This leads to respiratory difficulty, shallow breathing, and can result in severe breathing problems and insufficient oxygenation of the blood.

        Why the other options are wrong
        • A. Emphysema is characterized by the destruction of the alveolar walls, leading to decreased lung elasticity and increased air trapping.
        • C. Bronchitis is inflammation of the bronchial tubes, and asthma involves chronic inflammation and constriction of the airways.
        • D. Asthma is a chronic respiratory condition characterized by inflammation and narrowing of the airways, leading to recurrent episodes of wheezing, coughing, and shortness of breath. It is often triggered by various factors such as allergens, respiratory infections, exercise, or cold air.

        Q75. Deficiency of enzyme _ causes combined immunodeficiency syndrome.

        • A. Adenosine transcriptase
        • B. Adenosine transaminase
        • C. Adenosine polymerase
        • D. Adenosine deaminase

        Explanation: Adenosine deaminase deficiency (ADA deficiency) is an inherited condition that damages the immune system and is a common cause of severe combined immunodeficiency (SCID).

        Why the other options are wrong
        • A. This is not a recognized enzyme. There is no enzyme with this name in the context of immunodeficiency.
        • B. Transaminases are enzymes involved in amino acid metabolism, but adenosine transaminase is not a known enzyme. It is not associated with immunodeficiency.
        • C. There is no enzyme called adenosine polymerase. Polymerases are enzymes involved in DNA or RNA synthesis, but none are specifically named adenosine polymerase.

        Q76. Site of protein synthesis in cells are:

        • A. Ribosomes
        • B. Endoplasmic Reticulum
        • C. Nucleolus
        • D. Smooth Endoplasmic Reticulum

        Explanation: The site of protein synthesis in the cell are ribosomes. These are present attached to the surface of the rough endoplasmic reticulum and also in the free state in the cytoplasm. These organelles are involved in the process of translation which is the conversion of the mRNA to protein.

        Why the other options are wrong
        • B. SER is involved in synthesis of lipids.
        • C. It is involved in synthesis of ribosomes.
        • D. SER is involved in synthesis of lipids.

        Q77. Keeping correct balance of ions and water in our body is called as:

        • A. Thermoregulation
        • B. Osmoregulation
        • C. Excretion
        • D. Selective reabsorption

        Explanation: Osmoregulation is the process of maintaining salt and water balance (osmotic balance) across membranes within the body. Thermoregulation is a process that allows your body to maintain its core internal temperature. Excretion is a process in which metabolic waste is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin. Selective reabsorption is the process whereby certain molecules (e.g. ions, glucose and amino acids), after being filtered out of the capillaries along with nitrogenous waste products (i.e. urea) and water in the glomerulus, are reabsorbed from the filtrate as they pass through the nephron.

        Why the other options are wrong
        • A. Thermoregulation is a process that allows your body to maintain its core internal temperature.
        • C. Excretion is a process in which metabolic waste is eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin.
        • D. Selective reabsorption is the process whereby certain molecules (e.g. ions, glucose and amino acids), after being filtered out of the capillaries along with nitrogenous waste products (i.e. urea) and water in the glomerulus, are reabsorbed from the filtrate as they pass through the nephron.

        Q78. There are _ number of linkage groups in humans.

        • A. 46
        • B. 22
        • C. 80
        • D. 23

        Explanation: This phenomenon of staying together of all the genes of a chromosome is called linkage. Gene linkage is a physical relationship between genes. A chromosome carries its linked genes in the form of a linkage group. The number of linkage groups corresponds to the number of homologous pairs of chromosomes. Man has 23 linkage groups.

        Why the other options are wrong
        • A. This phenomenon of staying together of all the genes of a chromosome is called linkage. Gene linkage is a physical relationship between genes. A chromosome carries its linked genes in the form of a linkage group. The number of linkage groups corresponds to the number of homologous pairs of chromosomes. Man has 23 linkage groups.
        • B. This phenomenon of staying together of all the genes of a chromosome is called linkage. Gene linkage is a physical relationship between genes. A chromosome carries its linked genes in the form of a linkage group. The number of linkage groups corresponds to the number of homologous pairs of chromosomes. Man has 23 linkage groups.
        • C. This phenomenon of staying together of all the genes of a chromosome is called linkage. Gene linkage is a physical relationship between genes. A chromosome carries its linked genes in the form of a linkage group. The number of linkage groups corresponds to the number of homologous pairs of chromosomes. Man has 23 linkage groups.

        Q79. The actual or preserved remains of the organisms that lived in the ancient past are called:

        • A. Fossils
        • B. Impression
        • C. Ancient prints
        • D. Ancient cast

        Explanation: Fossils are the preserved remains, or traces of remains, of ancient organisms. An impression fossil is formed when the plant or animal decays completely but leaves behind an impression of itself.

        Why the other options are wrong
        • B. An impression fossil is formed when the plant or animal decays completely but leaves behind an impression of itself.
        • C. This term doesn't fit the given statement.
        • D. The term refers to any printed image, irrespective of the printing technique employed, that was created over a period of more than 600 years, from the beginning of printmaking in Europe to the end of the 18th century or early 19th century.

        Q80. Which one of the following cells does not have nucleus:

        • A. Eosinophils
        • B. Neutrophils
        • C. Basophils
        • D. Platelets

        Explanation: Platelets are irregularly shaped, have no nucleus, and typically measure only 2–3 micrometers in diameter. Platelets are not true cells, but are instead classified as cell fragments produced by megakaryocytes. Neutrophils, eosinophils and basophils are all types of white blood cells that contain nucleus.

        Why the other options are wrong
        • A. Eosinophils have nucleus.
        • B. Nuetrophils have nucleus.
        • C. Badophils possess nucleus.

        Q81. These structures are involved in the breakdown of old organelles:

        • A. Leucoplasts
        • B. Glyoxysomes
        • C. Lysosomes
        • D. Peroxisomes

        Explanation: Lysosomes are membrane-bounded, dense granular structures containing hydrolytic enzymes responsible mainly for intracellular and extracellular digestion. They are also involved in the process called autophagy (self-eating). In this process, some old parts of the cell, such as old mitochondria, are engulfed and digested by lysosomes.

        Why the other options are wrong
        • A. This is an incorrect option. The function of leucoplasts is to store starches and oils in plant cells. It is not involved in the breakdown of any substance or organelle.
        • B. This option is incorrect. Glyoxysomes are present in plant seeds rich in lipids. They are the sites for breakdown of fatty acids to succinate. They are not involved in breakdown of old organelles.
        • D. This is an incorrect option. This organelle is specifically involved in the formation and decomposition of hydrogen peroxide in the cell.

        Q82. Which combination is the example of ball and socket joints:

        • A. Hip and shoulder joints
        • B. Hip and knee joints
        • C. Shoulder and knee joints
        • D. Hip and elbow joints

        Explanation: The ball and socket joint also called as the spheroidal joint is a joint in which the ball-like rounded surface of a bone moves within a cup-like depression on another bone, this allows greater freedom of movement (full circle) than any other kind of joint. As evident from the figure, the shoulder joint and the hip joint are of ball and socket type. Whereas, the elbow, knee and ankle joints are hinge joints.

        Why the other options are wrong
        • B. The hip joint connects the thigh bone (femur) to the pelvic bone, allowing for leg movement and flexibility. It is a ball-and-socket joint. The knee joint connects the thigh bone (femur) to the shinbone (tibia) and kneecap (patella). It functions as a hinge joint, facilitating bending and straightening of the leg. Both joints are crucial for mobility and weight-bearing activities.
        • C. The shoulder joint is a ball-and-socket joint connecting the upper arm bone (humerus) to the shoulder blade (scapula). It provides a wide range of motion for arm movements. The knee joint is a hinge joint connecting the thigh bone (femur) to the shinbone (tibia) and kneecap (patella). It primarily allows for bending and straightening of the leg. Both joints are essential for various daily activities and movements.
        • D. The hip joint is a ball-and-socket joint connecting the thigh bone (femur) to the pelvic bone, facilitating leg movement and rotation. The elbow joint is a hinge joint connecting the upper arm bone (humerus) to the forearm bones (radius and ulna), allowing for bending and straightening of the arm.

        Q83. In aerobic respiration which of the following is correct?

        • A. Pyruvate is completely oxidized to form carbon dioxide and water
        • B. Pyruvate is completely oxidized to form oxygen and water
        • C. Pyruvate carboxylated to produce citrate
        • D. Pyruvate is converted to ethanol and carbon dioxide

        Explanation: In aerobic respiration, glucose is oxidised to form pyruvate during glycolysis. This is followed by Link reaction, Krebs cycle and Electron transport chain all of which leads to the formation of ATP, water and CO2.

        Why the other options are wrong
        • B. This option is incorrect because pyruvate itself is not oxidized to form oxygen and water. In aerobic respiration, oxygen (O2) is the terminal electron acceptor in the electron transport chain, but it is not formed during the oxidation of pyruvate. Pyruvate is oxidized to produce carbon dioxide (CO2) and high-energy electron carriers (NADH and FADH2) during the citric acid cycle.
        • C. This option is incorrect because the formation of citrate occurs during the first step of the citric acid cycle, where acetyl-CoA combines with oxaloacetate to form citrate. Pyruvate is not directly carboxylated to produce citrate. Pyruvate is first converted to acetyl-CoA in the mitochondria before entering the citric acid cycle.
        • D. This option is incorrect because it describes the process of alcoholic fermentation, not aerobic respiration. In alcoholic fermentation, pyruvate is converted to ethanol (alcohol) and carbon dioxide in the absence of oxygen. However, in aerobic respiration, pyruvate undergoes complete oxidation to produce carbon dioxide and water in the presence of oxygen.

        Q84. Yeasts, the unicellular fungi belongs mostly to the group:

        • A. Deuteromycota
        • B. Zygomycota
        • C. Basidiomycota
        • D. Ascomycota

        Explanation: Yeast is a eukaryotic organism that is single-celled and is classified under the kingdom of fungi. Most of the species of yeast reproduce asexually by budding. The most common species of yeast is the Saccharomyces cerevisiae which is used for fermentation and baking purpose. Ascomycetes are also called sac fungi because these fungi produce elongated sacs called asci. This is the largest subdivision of fungi and contains some very well-known genera such as Penicillium, Saccharomyces, Aspergillus, Neurospora, etc

        Why the other options are wrong
        • A. Some of the examples of the Deuteromycetes are Cercospora, Colletotrichum, Trichoderma, Pyricularia, and Fusarium.
        • B. Molds on fruits and bread are often (but certainly not always) from the Mucorales, as well as molds that form on dog poop (specifically, a genus called Phycomyces). You can also find a diverse assortment of former "Zygomycota" members parasitizing other fungi and insects.
        • C. The Phylum Basidiomycota is a major division of the Fungi. Known collectively as the Basidiomycetes fungi, this group includes mushrooms, smuts, rusts, the Cryptococcus pathogen, and others. This group contains both edible and poisonous species and includes an impressive range of sizes, colors, and shapes.

        Q85. The enzyme used by the bacteria to cut the DNA of the invading virus for its protection is:

        • A. Restriction Exonuclease
        • B. Restriction Ligase
        • C. Restriction Endonuclease
        • D. DNA polymerase

        Explanation: Restriction enzyme, also called restriction endonuclease, a protein produced by bacteria that cleaves DNA at specific sites along the molecule. In the bacterial cell, restriction enzymes cleave foreign DNA, thus eliminating infecting organisms.Specific endonucleases, also called restriction endonucleases, are available that cleave specific sites within a DNA sequence. Exonuclease is usually non-specific and does not have defensive properties against the entry of pathogenic microbes.Ligase is an enzyme that uses ATP to form bonds, and is used in recombinant DNA cloning to join restriction endonuclease fragments that have annealed. (There is no such thing as restriction ligase)A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA.

        Why the other options are wrong
        • A. Exonuclease is usually non-specific and does not have defensive properties against the entry of pathogenic microbes.
        • B. Ligase is an enzyme that uses ATP to form bonds and is used in recombinant DNA cloning to join restriction endonuclease fragments that have annealed. (There is no such thing as restriction ligase)
        • D. A DNA polymerase is a member of a family of enzymes that catalyze the synthesis of DNA molecules from nucleoside triphosphates, the molecular precursors of DNA.

        Q86. The number and sequence of amino acids along a polypeptide chain is called _ structure of a protein.

        • A. Quaternary
        • B. Tertiary
        • C. Primary
        • D. Secondary

        Explanation: Primary structure is the amino acid sequence.Secondary structure is local interactions between stretches of a polypeptide chain and includes α-helix and β-pleated sheet structures.Tertiary structure is the overall three-dimension folding driven largely by interactions between R groups.Quaternary structures is the orientation and arrangement of subunits in a multi-subunit protein.

        Why the other options are wrong
        • A. Quaternary structures is the orientation and arrangement of subunits in a multi-subunit protein.
        • B. Tertiary structure is the overall three-dimensional folding driven largely by interactions between R groups.
        • D. Secondary structure is local interactions between stretches of a polypeptide chain and includes a-helix and B-pleated sheet structures.

        Q87. Rod-shaped bacteria are known as _

        • A. Spirilla
        • B. Bacilli
        • C. Spirochete
        • D. Cocci

        Explanation: Bacilli are rod shaped bacteria. Cocci are spherical shaped bacteria. Spirillas are corkscrew shaped bacteria. Spirochetes are any group of spiral shaped bacteria.

        Why the other options are wrong
        • A. Spirillas are corkscrew shaped bacteria.
        • C. Spirochetes are any group of spiral shaped bacteria.
        • D. Cocci are spherical shaped bacteria.

        Q88. _ is the exact position of a gene on the chromosome.

        • A. Trait
        • B. Centromere
        • C. Genotype
        • D. Locus

        Explanation: A locus is a specific, fixed position on a chromosome where a particular gene or genetic marker is located.A phenotypic trait, simply trait, or character state is a distinct variant of a phenotypic characteristic of an organism.The centromere is the specialized DNA sequence of a chromosome that links a pair of sister chromatids.A genotype is an organism's complete set of genetic material. Often though, genotype is used to refer to a single gene or set of genes, such as the genotype for eye color.

        Why the other options are wrong
        • A. A phenotypic trait, simply trait, or character state is a distinct variant of a phenotypic characteristic of an organism.
        • B. The centromere is the specialized DNA sequence of a chromosome that links a pair of sister chromatids.
        • C. A genotype is an organism's complete set of genetic material. Often though, genotype is used to refer to a single gene or set of genes, such as the genotype for eye colour.

        Q89. Parathormone production is controlled by the blood:

        • A. Ca level
        • B. Sugar level
        • C. Na level
        • D. Mg level

        Explanation: Parathyroid hormone is mainly controlled by the negative feedback of calcium levels in the blood to the parathyroid glands. Low calcium levels in the blood stimulate parathyroid hormone secretion, whereas high calcium levels in the blood prevent the release of parathyroid hormone.

        Why the other options are wrong
        • B. Insulin and glucagon production is controlled by it.
        • C. Aldosterone production is controlled by it.
        • D. This option is incorrect.

        Q90. Which one of the following act as a PACEMAKER in heart:

        • A. Bundle of His
        • B. Atrioventricular node
        • C. Atrioventricular bundles of fibers
        • D. Sinoatrial node

        Explanation: Electrical impulses from the heart muscle cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located at the top of the heart's upper-right chamber (the right atrium). The SA node is known as the heart's “natural pacemaker. The bundle of His is a collection of heart muscle cells specialized for electrical conduction that transmits the electrical impulses from the AV node (located between the atria and the ventricles) to the point of the apex of the fascicular branches via the bundle branches. The atrioventricular node or AV node is a part of the electrical conduction system of the heart that coordinates the top of the heart. It electrically connects the atria and ventricles.

        Why the other options are wrong
        • A. The bundle of His is a collection of heart muscle cells specialised for electrical conduction that transmits the electrical impulses from the AV node (located between the atria and the ventricles) to the point of the apex of the fascicular branches via the bundle branches.
        • B. The atrioventricular (AV) node is a cluster of cells in the heart that regulates the electrical signal between the atria and ventricles. It acts as a relay station, slowing down the electrical impulse, allowing the ventricles to fill with blood before contracting and pumping it out to the rest of the body.
        • C. The atrioventricular node or AV node is a part of the electrical conduction system of the heart that coordinates the top of the heart. It electrically connects the atria and ventricles.

        Q91. Single ringed pyrimidines are:

        • A. Uracil, Cytosine and Thymine
        • B. Cytosine, Guanine and Uracil
        • C. Adenine and Guanine
        • D. Cytosine, Adenine and Thymine

        Explanation: The pyrimidines, Thymine, Cytosine and Uracil, are smaller and have a single ring, while the purines, Adenine and Guanine, are larger and have two rings.

        Why the other options are wrong
        • B. Single-ring nitrogenous bases are called pyrimidines, while double-ringed structures are called purines. Pyrimidines include Cytosine, Thymine (only in DNA), and Uracil (only in RNA). Purines include Adenine and Guanine.
        • C. Single-ring nitrogenous bases are called pyrimidines, while double-ringed structures are called purines. Pyrimidines include Cytosine, Thymine (only in DNA), and Uracil (only in RNA). Purines include Adenine and Guanine.
        • D. Single-ring nitrogenous bases are called pyrimidines, while double-ringed structures are called purines. Pyrimidines include Cytosine, Thymine (only in DNA), and Uracil (only in RNA). Purines include Adenine and Guanine.

        Q92. Which one of the following is Multiple allelic characters?

        • A. Colour of flower in pea plant
        • B. Blood group of the human being
        • C. Shape of seed in pea plant
        • D. Length of stem in pea plant

        Explanation: Multiple alleles are the alternative forms of the same gene so they influence the same trait. An excellent example of multiple allele inheritance is human blood type. Blood type exists as four possible phenotypes: A, B, AB, & O. There are 3 alleles for the gene that determines blood type.

        Why the other options are wrong
        • A. It is the incorrect option.
        • C. It is the incorrect option.
        • D. It is the incorrect option.

        Q93. Which statement is correct about atrial systole?

        • A. Atria relax and ventricles contract
        • B. Atria contract and ventricle also contract
        • C. Atria and ventricles are relaxed
        • D. Ventricles remain relax while atria contract

        Explanation: During atrial systole following events occur: • AV valves open • SL valves close • Muscles of atria contract and pump blood to ventricles • Ventricles are relaxed and receive blood from atria.

        Why the other options are wrong
        • A. It is incorrect. Atria will contract and ventricles will relax.
        • B. It is incorrect.Atria will contract and ventricles will relax.
        • C. It is incorrect. Atria will contract and ventricles will relax.

        Q94. Growth in the larva of young arthropods is restricted by:

        • A. Exoskeleton
        • B. Appendages
        • C. Endoskeleton
        • D. Reduced mitosis

        Explanation: As the body underneath the exoskeleton grows, the animal begins to outgrow its tough exterior. In order to cope with this situation, arthropods undergo a process of shedding their exoskeleton and forming a new one periodically throughout their lifetime. This process is called molting, or ecdysis.

        Why the other options are wrong
        • B. As the body underneath the exoskeleton grows, the animal begins to outgrow its tough exterior. In order to cope with this situation, arthropods undergo a process of shedding their exoskeleton and forming a new one periodically throughout their lifetime. This process is called molting, or ecdysis.
        • C. As the body underneath the exoskeleton grows, the animal begins to outgrow its tough exterior. In order to cope with this situation, arthropods undergo a process of shedding their exoskeleton and forming a new one periodically throughout their lifetime. This process is called molting, or ecdysis.
        • D. As the body underneath the exoskeleton grows, the animal begins to outgrow its tough exterior. In order to cope with this situation, arthropods undergo a process of shedding their exoskeleton and forming a new one periodically throughout their lifetime. This process is called molting, or ecdysis.

        Q95. At the last step of Glycolysis, which of the following compound is formed:

        • A. Pyruvic acid/ Pyruvate
        • B. Lactic acid
        • C. Ethyl Alcohol
        • D. Fructose Phosphate

        Explanation: The last step in glycolysis is catalysed by the enzyme pyruvate kinase. Conversion of the PEP into pyruvate results in the production of a second ATP molecule by substrate-level phosphorylation and the compound pyruvic acid (or its salt form, pyruvate).

        Why the other options are wrong
        • B. It is incorrect as last step in glycolysis is catalysed by the enzyme pyruvate kinase. Conversion of the PEP into pyruvate results in the production of a second ATP molecule by substrate-level phosphorylation and the compound pyruvic acid (or its salt form, pyruvate).
        • C. It is incorrect as last step in glycolysis is catalysed by the enzyme pyruvate kinase. Conversion of the PEP into pyruvate results in the production of a second ATP molecule by substrate-level phosphorylation and the compound pyruvic acid (or its salt form, pyruvate).
        • D. It is incorrect as last step in glycolysis is catalysed by the enzyme pyruvate kinase. Conversion of the PEP into pyruvate results in the production of a second ATP molecule by substrate-level phosphorylation and the compound pyruvic acid (or its salt form, pyruvate).

        Q96. NADP, nicotinamide adenine dinucleotide phosphate, is a carrier of:

        • A. OH group
        • B. O2 group
        • C. Hydrogen
        • D. Phosphate

        Explanation: NADP+ is a coenzyme that functions as a universal electron carrier, accepting electrons and hydrogen atoms to form NADPH, or nicotinamide adenine dinucleotide phosphate.

        Why the other options are wrong
        • A. It is incorrect as NADP+ is a coenzyme that functions as a universal electron carrier, accepting electrons and hydrogen atoms to form NADPH, or nicotinamide adenine dinucleotide phosphate.
        • B. It is incorrect as NADP+ is a coenzyme that functions as a universal electron carrier, accepting electrons and hydrogen atoms to form NADPH, or nicotinamide adenine dinucleotide phosphate.
        • D. It is incorrect as NADP+ is a coenzyme that functions as a universal electron carrier, accepting electrons and hydrogen atoms to form NADPH, or nicotinamide adenine dinucleotide phosphate.

        Q97. When filtration is completed the waste products through distal tube of Nephrons empties to:

        • A. Efferent Arteriole
        • B. Collecting Tubules
        • C. Peritubular capillaries
        • D. Proximal tubules

        Explanation: When filtration is completed the waste products through distal tube of Nephrons empties to the collecting duct which carries the waste product emptying into the renal pelvis.At the distal end of the glomerulus, the capillaries rejoin to form the efferent arteriole through which blood leaves the glomerulus.In the renal system, peritubular capillaries are tiny blood vessels, supplied by the efferent arteriole, that travel alongside nephrons allowing reabsorption and secretion between blood and the inner lumen of the nephron.The proximal tubule is the segment of the nephron in kidneys which begins from the renal pole of the Bowman's capsule to the beginning of loop of Henle

        Why the other options are wrong
        • A. At the distal end of the glomerulus, the capillaries rejoin to form the efferent arteriole through which blood leaves the glomerulus.
        • C. In the renal system, peritubular capillaries are tiny blood vessels, supplied by the efferent arteriole, that travel alongside nephrons allowing reabsorption and secretion between blood and the inner lumen of the nephron.
        • D. The proximal tubule is the segment of the nephron in kidneys which begins from the renal pole of the Bowman's capsule to the beginning of loop of Henle.

        Q98. Blood solute potential is controlled by the following hormone.

        • A. Estrogen
        • B. Epinephrine
        • C. Thyroxine
        • D. Vasopressin

        Explanation: ADH is also called arginine vasopressin. It's a hormone made by the hypothalamus in the brain and stored in the posterior pituitary gland. It tells your kidneys how much water to conserve. ADH constantly regulates and balances the amount of water in your blood, hence managing the solute potential.Estrogen is a hormone that plays various roles in the body. In females, it helps develop and maintain both the reproductive system and female characteristics, such as breasts and pubic hair.Epinephrine, more commonly known as adrenaline, is a hormone secreted by the medulla of the adrenal glands. Strong emotions such as fear or anger cause epinephrine to be released into the bloodstream, which causes an increase in heart rate, muscle strength, blood pressure, and sugar metabolismThyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones

        Why the other options are wrong
        • A. Estrogen is a hormone that plays various roles in the body. In females, it helps develop and maintain both the reproductive system and female characteristics, such as breasts and pubic hair.
        • B. Epinephrine, more commonly known as adrenaline, is a hormone secreted by the medulla of the adrenal glands. Strong emotions such as fear or anger cause epinephrine to be released into the bloodstream, which causes an increase in heart rate, muscle strength, blood pressure, and sugar metabolism
        • C. Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development and maintenance of bones.

        Q99. The temperature that promotes the maximum activity of enzymes is referred to as:

        • A. Fixed temperature
        • B. Optimum temperature
        • C. Controlled temperature
        • D. Active temperature

        Explanation: The temperature that promotes the maximum activity of enzymes is referred to as the "optimum temperature." Each enzyme has an optimal temperature at which it functions most efficiently. This temperature allows the enzyme to reach its maximum catalytic activity, as the kinetic energy of the molecules is sufficient for effective collisions between the enzyme and its substrate. The optimum temperature can vary among different enzymes and is typically close to the normal physiological temperature of the organism from which the enzyme is derived. For many enzymes in human cells, the optimum temperature is around 37 degrees Celsius (98.6 degrees Fahrenheit), which is the normal body temperature for humans.

        Why the other options are wrong
        • A. The temperature that promotes the maximum activity of enzymes is referred to as the "optimum temperature." Each enzyme has an optimal temperature at which it functions most efficiently. This temperature allows the enzyme to reach its maximum catalytic activity, as the kinetic energy of the molecules is sufficient for effective collisions between the enzyme and its substrate.
        • C. The temperature that promotes the maximum activity of enzymes is referred to as the "optimum temperature." Each enzyme has an optimal temperature at which it functions most efficiently. This temperature allows the enzyme to reach its maximum catalytic activity, as the kinetic energy of the molecules is sufficient for effective collisions between the enzyme and its substrate.
        • D. The temperature that promotes the maximum activity of enzymes is referred to as the "optimum temperature." Each enzyme has an optimal temperature at which it functions most efficiently. This temperature allows the enzyme to reach its maximum catalytic activity, as the kinetic energy of the molecules is sufficient for effective collisions between the enzyme and its substrate.

        Q100. Divergent Evolution produces:

        • A. Vital Organs
        • B. Homologous Organs
        • C. Vestigial Organs
        • D. Analogous Organs

        Explanation: Homologous organs are created in divergent evolution. Homologous organs refer to the organs with similar structures but having different functions. The evolution of apes and humans from common primate ancestors is an example of divergent evolution.

        Why the other options are wrong
        • A. The human body contains five organs that are considered vital for survival. They are the heart, brain, kidneys, liver, and lungs.
        • C. Vestigial organs are rudimentary anatomical structures that are retained in a species despite having lost their primary ancestral function. These structures often lack an apparent purpose, in contrast to the full functionality of these organs observed in closely related and ancestral species.
        • D. Analogous structures are anatomically different but perform similar functions and hence are a result of convergent evolution. It occurs when two groups of largely unrelated organisms are exposed to very similar environments and develop similar adaptations to survive.

        Q101. Tonoplast bounds which organelle:

        • A. Golgi complex
        • B. Nucleus
        • C. Endoplasmic Reticulum
        • D. Vacuoles

        Explanation: A cell can have membrane bound organelles and non-membrane bound organelles. Membrane bound organelles are mitochondria, endoplasmic reticulum, vacuoles, lysosomes, Golgi apparatus, plastids. Membrane which occurs around the vacuole is called a tonoplast and separates the contents of the vacuole from the cytoplasm.

        Why the other options are wrong
        • A. It is not bound by tonoplast.
        • B. It is surrounded by nuclear envelope.
        • C. It is not bound by tonoplast.

        Q102. Antivenom given after a snake bite venom is an example of:

        • A. Artificial active immunity
        • B. Specific natural immunity
        • C. Artificial passive immunity
        • D. Natural passive immunity

        Explanation: "The explanation for this question will be added soon!".

        Why the other options are wrong
        • A. This type of immunity is obtained through vaccination, where the individual's immune system is exposed to an antigen, leading to the production of antibodies. Snake antivenom is not a vaccine, and it provides pre-formed antibodies, so it doesn't fit this category.
        • B. This term is not commonly used in immunology. Natural immunity generally refers to the body's natural defense mechanisms, while specific immunity can be active or passive but doesn't specify the source of immunity.
        • D. This form of immunity is gained when a baby receives antibodies from its mother through breast milk or the placenta. It's not the case with snake antivenom, which is artificially produced.

        Q103. The cisternae breaks up into vesicles from _ , _ of Golgi complex.

        • A. Convex, maturing face
        • B. Concave, forming face
        • C. Convex, forming face
        • D. Concave, maturing face

        Explanation: The trans face of golgi apparatus (concave surface) where the cisternae breaks up to form new vesicles is also known as the maturing face.

        Why the other options are wrong
        • A. The trans face of golgi apparatus (concave surface) where the cisternae breaks up to form new vesicles is also known as the maturing face.
        • B. The trans face of golgi apparatus (concave surface) where the cisternae breaks up to form new vesicles is also known as the maturing face.
        • C. The trans face of golgi apparatus (concave surface) where the cisternae breaks up to form new vesicles is also known as the maturing face.

        Q104. Which hormone causes the contraction walls of the uterus during the process of birth?

        • A. FSH
        • B. STH
        • C. Oxytocin
        • D. LTH

        Explanation: The hormone that plays a crucial role in causing the contraction of the uterine walls during the process of birth is oxytocin. Oxytocin is produced by the hypothalamus and released by the pituitary gland. It stimulates the muscles of the uterus to contract, leading to the progression of labor and ultimately the delivery of the baby. Oxytocin also plays a role in facilitating bonding between the mother and the newborn and in promoting milk ejection during breastfeeding.

        Why the other options are wrong
        • A. Follicle stimulating hormone is one of the hormones essential to pubertal development and the function of women's ovaries and men's testes. In women, this hormone stimulates the growth of ovarian follicles in the ovary before the release of an egg from one follicle at ovulation.
        • B. Growth hormone (GH) or somatotropin, also known as human growth hormones (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals.
        • D. Prolactin, also known as lactotropin (LTH), is a protein best known for its role in enabling mammals, usually females, to produce milk.

        Q105. Which of the following is Unsaturated “Fatty Acid”?

        • A. Stearic Acid
        • B. Palmitic Acid
        • C. Butyric Acid
        • D. Oleic Acid

        Explanation: Oleic acid is a mono-unsaturated omega-9 fatty acid found in various animal and vegetable sources.

        Why the other options are wrong
        • A. Stearic acid is a saturated fatty acid with an 18-carbon chain. The IUPAC name is octadecanoic acid.
        • B. Palmitic acid is a fatty acid with a 16-carbon chain. It is the most common saturated fatty acid found in animals, plants and microorganisms.
        • C. Butyric Acid is a saturated short-chain fatty acid with a 4-carbon backbone. Butyric acid is commonly found in esterified form in animal fats and plant oils.

        Q106. When we extract Carotenoids from its source we see that it is:

        • A. Violet in color
        • B. Blue green in color
        • C. Yellow green in color
        • D. Yellow to orange red in color

        Explanation: Carotenoids also called tetraterpenoids, are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, and fungi.

        Why the other options are wrong
        • A. It is incorrect.
        • B. It is incorrect.
        • C. It is incorrect.

        Q107. When two or more alleles do not show complete dominance or both the alleles are expressing independently in heterozygotic conditions. Such a condition is called:

        • A. Complete dominance
        • B. Over-dominance
        • C. Codominance
        • D. Incomplete dominance

        Explanation: Codominance, as it relates to genetics, refers to a type of inheritance in which two versions (alleles) of the same gene are expressed separately to yield different traits in an individual.

        Why the other options are wrong
        • A. Complete dominance is a form of dominance where in the dominant allele completely masks the effect of the recessive allele in heterozygous conditions. A gene (or allele) shows dominance when it suppresses the expression — or dominates the effects — of the recessive gene (or allele).
        • B. In overdominance, the heterozygote produced by two homozygous parents show a phenotype that is more pronounced than that of the parents.
        • D. Incomplete dominance is a form of Gene interaction in which both alleles of a gene at a locus are partially expressed, often resulting in an intermediate or different phenotype. It is also known as partial dominance.

        Q108. Taste buds on the tongue are example of:

        • A. Thermoreceptors
        • B. Photoreceptors
        • C. Mechanoreceptors
        • D. Chemoreceptors

        Explanation: The taste receptors are located around the small structures known as papillae found on the upper surface of the tongue, these are chemoreceptors.

        Why the other options are wrong
        • A. These are present in the skin dermis for detection of change in temperature. They include ruffini ending for heat and krause end bulbs for cold.
        • B. These are receptors present in eyes for the detection of light. For example rods and cone cells in the retina.
        • C. Mechanoreceptors are specialized sensory receptors that respond to mechanical stimuli such as touch, pressure, vibration, and stretch. They are responsible for detecting and transmitting information related to mechanical forces and changes in the environment.

        Q109. Which of the following hormones acts on the uterus wall for thickening?

        • A. Progesterone
        • B. Zona pellucida
        • C. Follicle stimulating hormone
        • D. Oxytocin

        Explanation: The hormone that acts on the uterus wall (endometrium) for thickening is progesterone. Progesterone is a steroid hormone that plays a key role in the menstrual cycle and the preparation of the uterus for potential pregnancy. During the menstrual cycle, after ovulation occurs, the ruptured follicle transforms into a structure called the corpus luteum. The corpus luteum is responsible for producing progesterone. Progesterone acts on the endometrial lining of the uterus to prepare it for the possible implantation of a fertilized egg.

        Why the other options are wrong
        • B. Zona pellucida is the thick transparent membrane surrounding a mammalian ovum before implantation.
        • C. In women, FSH helps control the menstrual cycle and stimulates the growth of eggs in the ovaries. FSH levels in women change throughout the menstrual cycle, with the highest levels happening just before an egg is released by the ovary.
        • D. The two main actions of oxytocin in the body are contraction of the womb (uterus) during childbirth and lactation.

        Q110. If concentration time graph of a reactant indicates a constant half life, then the order reaction with respect to that reactant is:

        • A. Zero order
        • B. Half order
        • C. Second order
        • D. First order

        Explanation: In First order reactions, the graph represents the half-life is different from zero order reaction in a way that the slope continually decreases as time progresses until it reaches zero. We can also easily see that the length of half-life will be constant, independent of concentration. For example, it takes the same amount of time for the concentration to decrease from one point to another point. The half-life of zero order reaction decreases as the concentration decreases. The half life of second order reactions increases as the concentration increases.

        Why the other options are wrong
        • A. If the concentration-time graph of a reactant indicates a constant half-life, the reaction is a first-order reaction with respect to that reactant. In first-order reactions, the half-life remains constant, and the rate of the reaction is directly proportional to the concentration of the reactant. Therefore this option is not correct.
        • B. If the concentration-time graph of a reactant indicates a constant half-life, the reaction is a first-order reaction with respect to that reactant. In first-order reactions, the half-life remains constant, and the rate of the reaction is directly proportional to the concentration of the reactant. Therefore this option is not correct.
        • C. If the concentration-time graph of a reactant indicates a constant half-life, the reaction is a first-order reaction with respect to that reactant. In first-order reactions, the half-life remains constant, and the rate of the reaction is directly proportional to the concentration of the reactant. Therefore this option is not correct.

        Q111. Which of the following catalysts is used in the below reaction?

        • A. Conc. H2SO4
        • B. Purnice stone
        • C. Pt
        • D. Ni

        Explanation: Esterification process is a slow process when it is performed at room temperature also the process does not complete at all in the room temperature. So to complete the process of esterification there should be something to complete the process as well as to speed up the process. Thus concentrated sulphuric acid is added. It is a catalyst which will speed up the process and esterification will proceed speedily and complete on time. Also concentrated sulphuric acid has a property to remove water. Therefore it also acts as a dehydrating agent. After adding this will take reaction in the equilibrium position and will be able to give a greater yield of ester as result.

        Why the other options are wrong
        • B. False.
        • C. False.
        • D. False.

        Q112. Halothane is a halo derivative of:

        • A. Methane
        • B. Ethane
        • C. Methanol
        • D. Ethanol

        Explanation: The chemical Formula for Halothane is F3CCHBRCI, which is a derivative of the chemical formula of Ethane (C2H6).

        Why the other options are wrong

          Q113. The species which are produced by heterolytic bond breaking and can act as electron pair donors are known as:

          • A. Nucleophiles
          • B. Cations
          • C. Free radicals
          • D. Anions

          Explanation: A nucleophile is a chemical species that donates an electron pair to form a chemical bond in relation to a reaction. Heterolytic bond cleavage (heterolytic cleavage; heterolysis): Bond breaking in which the bonding electron pair is split unevenly between the products. Heterolytic cleavage often produces at least one ion.Cation is a positively charged ion.Anion is a negatively charged ion.A free radical is an atom, molecule, or ion that has an unpaired valence electron.

          Why the other options are wrong
          • B. Cation is a positively charged ion.
          • C. A free radical is an atom, molecule, or ion that has an unpaired valence electron.
          • D. Anion is a negatively charged ion.

          Q114. The product of the concentrations of each ion in a saturated solution of a sparingly soluble salt at 298 K, raised to the power of their relative concentrations is:

          • A. Ksp
          • B. Ka
          • C. Kw
          • D. Kb

          Explanation: Solubility product, Ksp, is the mathematical product of the dissolved ions concentration raised to the power of their stoichiometric coefficients.An acid dissociation constant (Ka) is a quantitative measure of the strength of an acid in solution.Kb is the base dissociation constant. The base dissociation constant is a measure of how completely a base dissociates into its component ions in water.The equilibrium constant, Kw, is called the dissociation constant or ionization constant of water.

          Why the other options are wrong
          • B. An acid dissociation constant (Ka ) is a quantitative measure of the strength of an acid in solution
          • C. The equilibrium constant, Kw, is called the dissociation constant or ionisation constant of water.
          • D. Kb is the base dissociation constant. The base dissociation constant is a measure of how completely a base dissociates into its component ions in water. The equilibrium constant, Kw, is called the dissociation constant or ionisation constant of water.

          Q115. The catalyst used for the manufacture of H2SO4 by contact process is:

          • A. SO3
          • B. V2O5
          • C. Fe2O3
          • D. Pt/Pd

          Explanation: The contact process is one of the most common methods of forming Sulphuric acid. In this process not only Sulphuric acid is formed, but Oleum and Sulphur trioxide is also formed. First, Sulphur dioxide and oxygen are combined in a 1:1 ratio. And it is then treated with the catalyst Vanadium pentoxide at a temperature between (400-450)° and pressure. This converts the Sulphur dioxide into Sulphur trioxide Now this Sulphur trioxide formed is reacted with Sulphuric acid in order to dilute it. In this process Oleum is formed. This Oleum formed is then diluted with water to ultimately yield Sulphuric acid: Therefore, the catalyst used in making the contact process is Vanadium pentoxide.

          Why the other options are wrong
          • A. The catalyst used for the manufacture of H2SO4 (sulfuric acid) by the contact process is vanadium(V) oxide, often represented as V₂O₅. Therefore this option is not correct.
          • C. The catalyst used for the manufacture of H2SO4 (sulfuric acid) by the contact process is vanadium(V) oxide, often represented as V₂O₅. Therefore this option is not correct.
          • D. The catalyst used for the manufacture of H2SO4 (sulfuric acid) by the contact process is vanadium(V) oxide, often represented as V₂O₅. Therefore this option is not correct.

          Q116. Ligands having two lone pair of electrons for donation to the central transition metal ion are known as:

          • A. Polydentate ligands
          • B. Monodentate ligand
          • C. Bidentate ligands
          • D. Hexadentate ligands

          Explanation: Bidentate ligands have two lone pairs, both of which can bond to the central metal ion. Monodentate ligand is a ligand that has only one atom that coordinates directly to the central atom in a complex. A polydentate ligand is a ligand that is attached to a central metal ion by bonds from two or more donor atoms. A hexadentate ligand in coordination chemistry is a ligand that combines with a central metal atom with six bonds.

          Why the other options are wrong
          • A. Polydentate ligand is attached to a central metal ion by bonds from two or more donor atoms. EDTA, a hexadentate ligand, is an example of a polydentate ligand that has six donor atoms with electron pairs that can be used to bond to a central metal atom or ion.
          • B. Monodentate ligands are Lewis bases that donate a single pair ("mono") of electrons to a metal atom. Monodentate ligands can be either ions (usually anions) or neutral molecules.
          • D. A hexadentate ligand in coordination chemistry is a ligand that combines with a central metal atom with six bonds.

          Q117. The stability in the following structure is due to the:

          • A. Weak Van Der Waal’s forces.
          • B. Disulfide bridges.
          • C. Presence of unpaired electron in the structure.
          • D. Hydrogen bonding between NH group of one peptide and CO group of another peptide.

          Explanation: The alpha helix (α-helix) is a type of secondary structure of proteins and is in a right hand-helix conformation in which every backbone N−H group hydrogen bonds to the backbone C=O. group of the amino acid located three or four residues earlier along the protein sequence.

          Why the other options are wrong
          • A. Hydrogen bonding plays a crucial role in stabilizing the structure of proteins, contributing to their overall stability and function. In proteins, hydrogen bonds form between the hydrogen atoms of amino acid residues and other atoms, such as oxygen or nitrogen, within the same protein molecule. These bonds help maintain the secondary and tertiary structures of proteins. In the secondary structure, hydrogen bonds are prominent in stabilizing structures like alpha helices and beta sheets. These bonds result from interactions between the carbonyl group (C=O) of one amino acid and the amino group (N-H) of another along the polypeptide chain. In the tertiary structure, hydrogen bonds contribute to the overall folding of the protein into its three-dimensional shape. They can occur between different parts of the polypeptide chain, reinforcing the specific folding pattern. The strength and specificity of hydrogen bonds make them essential in maintaining the integrity and stability of protein structures, influencing their biological functions. Therefore, this option is not correct.
          • B. Hydrogen bonding plays a crucial role in stabilizing the structure of proteins, contributing to their overall stability and function. In proteins, hydrogen bonds form between the hydrogen atoms of amino acid residues and other atoms, such as oxygen or nitrogen, within the same protein molecule. These bonds help maintain the secondary and tertiary structures of proteins. In the secondary structure, hydrogen bonds are prominent in stabilizing structures like alpha helices and beta sheets. These bonds result from interactions between the carbonyl group (C=O) of one amino acid and the amino group (N-H) of another along the polypeptide chain. In the tertiary structure, hydrogen bonds contribute to the overall folding of the protein into its three-dimensional shape. They can occur between different parts of the polypeptide chain, reinforcing the specific folding pattern. The strength and specificity of hydrogen bonds make them essential in maintaining the integrity and stability of protein structures, influencing their biological functions. Therefore, this option is not correct.
          • C. Hydrogen bonding plays a crucial role in stabilizing the structure of proteins, contributing to their overall stability and function. In proteins, hydrogen bonds form between the hydrogen atoms of amino acid residues and other atoms, such as oxygen or nitrogen, within the same protein molecule. These bonds help maintain the secondary and tertiary structures of proteins. In the secondary structure, hydrogen bonds are prominent in stabilizing structures like alpha helices and beta sheets. These bonds result from interactions between the carbonyl group (C=O) of one amino acid and the amino group (N-H) of another along the polypeptide chain. In the tertiary structure, hydrogen bonds contribute to the overall folding of the protein into its three-dimensional shape. They can occur between different parts of the polypeptide chain, reinforcing the specific folding pattern. The strength and specificity of hydrogen bonds make them essential in maintaining the integrity and stability of protein structures, influencing their biological functions. Therefore, this option is not correct.

          Q118. Which is the structure of polyvinyl chloride (polychloroethane)?

          • A. -[CCl2-CCl2]-
          • B. -[HCCl-CH-Cl]-
          • C. [H2C=CH-Cl]
          • D. -[H2C-CH-Cl]-

          Explanation: Poly(vinyl chloride) (PVC) is a synthetic resin made from vinyl chloride and is a member of a large family of polymers broadly referred to as “vinyls.” The chemical formula for vinyl chloride is H2C=CHCl, and the formula for PVC is (H2C–CHCl)n, where n is the degree of polymerization.

          Why the other options are wrong

            Q119. Nylon-6,6 is also called:

            • A. Poly styrene
            • B. Polyester
            • C. Polyamide
            • D. Polyvinyl alcohol

            Explanation: Nylon-6,6 is a synthetic polymer called a polyamide because of the characteristic monomers of amides in the backbone chainPolystyrene is a plastic. It is made up of many styrenes. Styrene is a small organic compound with the chemical formula C6H5CH=CH2.Polyester is a synthetic fabric that's usually derived from petroleum. This fabric is one of the world's most popular textiles, and it is used in thousands of different consumer and industrial applications. Chemically, polyester is a polymer primarily composed of compounds within the ester functional group.Poly is a water-soluble synthetic polymer. It has the idealized formula [CH₂CH]ₙ.

            Why the other options are wrong
            • A. Polystyrene is a plastic. It is made up of many styrenes. Styrene is a small organic compound with the chemical formula C6H5CH=CH2.
            • B. Polyester is a synthetic fabric that's usually derived from petroleum. This fabric is one of the world's most popular textiles, and it is used in thousands of different consumer and industrial applications. Chemically, polyester is a polymer primarily composed of compounds within the ester functional group.
            • D. PVA is partially crystalline upon formation and is characterised by properties such as chemical resistance, water solubility, and biodegradability. The similarity in physical properties makes it compatible with human tissues.

            Q120. Which compound will be produced by the oxidation of ethanal by acidified K2Cr2O7 ?

            • A. Ethene
            • B. Ethanol
            • C. Ethanoic acid
            • D. Ethanone

            Explanation: Aldehyde when undergoes oxidation reaction in presence of acidified potassium dichromate or alkaline potassium permanganate forms carboxylic acid as a product.

            Why the other options are wrong
            • A. Aldehyde when undergoing oxidation reaction in presence of acidified potassium dichromate or alkaline potassium permanganate forms carboxylic acid as a product.
            • B. Aldehyde when undergoing oxidation reaction in presence of acidified potassium dichromate or alkaline potassium permanganate forms carboxylic acid as a product.
            • D. Aldehyde when undergoing oxidation reaction in presence of acidified potassium dichromate or alkaline potassium permanganate forms carboxylic acid as a product.

            Q121. Alcohol in which carbon atom bonded to OH group is further attached with three alkyl group is:

            • A. Tertiary alcohol
            • B. Primary alcohol
            • C. Aromatic alcohol
            • D. Secondary alcohol

            Explanation: A tertiary (3°) alcohol is one in which the carbon atom with the OH group is attached to three other carbon atoms. Its general formula is R3COH Primary alcohols are those alcohols where the carbon atom of the hydroxyl group (OH) is attached to only one single alkyl group. The aromatic alcohols or aryl-alcohols are a class of chemical compounds containing a hydroxyl group (—OH) bonded directly to an aromatic hydrocarbon group. A secondary alcohol is a compound in which a hydroxyl group( ‒OH) is attached to a saturated carbon atom which has two other carbon atoms attached to it.

            Why the other options are wrong
            • B. Primary alcohols are those alcohols where the carbon atom of the hydroxyl group (OH) is attached to only one single alkyl group.
            • C. The aromatic alcohols or aryl- alcohols are a class of chemical compounds containing a hydroxyl group (-OH) bonded directly to an aromatic hydrocarbon group.
            • D. A secondary alcohol is a compound in which a hydroxyl group(-OH) is attached to a saturated carbon atom which has two other carbon atoms attached to it.

            Q122. The following sketch shows the variation in a physical property of third period elements against their atomic numbers: What physical property is plotted in this sketch?

            • A. Ionization energy
            • B. Melting point
            • C. Ionic radius
            • D. Atomic radius

            Explanation: Na, Mg, Al, Si are all GIANT LATTICE structures involving either metallic (Na, Mg, Al) or giant covalent macromolecule (Si) bonding. Whereas, P, S, Cl are COVALENT MOLECULES, with Ar being a monatomic nonmetal gas. Melting is achieved by disrupting the considerably weaker van der Waals intermolecular forces that exist between the molecules. Melting point steadily increases between Na and Al due to: increased metal cation charge (more protons), more delocalised e− per atom, smaller sized metal ions, hence stronger electrostatic attraction between cations and delocalised e− therefore stronger metallic bonding. Silicon has a significantly higher melting point because Silicon is a giant covalent macromolecule. In order to melt Silicon there is a need to break down many strong covalent bonds between Si atoms, that can only be achieved by applying considerable energy. Melting point of S8 > P4 > Cl2 > Ar because there is decreasing strength of vdW intermolecular forces of attraction as there is a decreasing size of molecule. This explanation is based on the known correlation between molecular size (molecular mass) and magnitude of vdW force of attraction between molecules.

            Why the other options are wrong
            • A. The ionization energy is a measure of the capability of an element to enter into chemical reactions requiring ion formation or donation of electrons. It is also generally related to the nature of the chemical bonding in the compounds formed by the elements. See also binding energy; electron affinity.
            • C. The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius
            • D. The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius.

            Q123. The standard electrode potential of hydrogen is arbitrarily taken at 298 K is _

            • A. 0.00 volt
            • B. 0.10 volt
            • C. 10.0 volt
            • D. 1.00 volt

            Explanation: SHE is a redox electrode which forms the basis of oxidation-reduction potential. The standard electrode potential value of hydrogen is declared to be zero.

            Why the other options are wrong
            • B. The standard electrode potential value of hydrogen is declared to be zero.
            • C. The standard electrode potential value of hydrogen is declared to be zero.
            • D. The standard electrode potential value of hydrogen is declared to be zero.

            Q124. The potential difference of an electrochemical cell is measured by:

            • A. Ammeter
            • B. Voltmeter
            • C. Galvanometer
            • D. Calorimeter

            Explanation: A voltmeter is an instrument used for measuring the electric potential difference between two points in an electric circuit. An ammeter (from an ampere meter) is a measuring instrument used to measure the current in a circuit. A galvanometer is an electromechanical instrument used for detecting and indicating an electric current. A calorimeter is an object used for calorimetry or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity.

            Why the other options are wrong
            • A. An ammeter (from an ampere meter) is a measuring instrument used to measure the current in a circuit.
            • C. A galvanometer is an electromechanical instrument used for detecting and indicating an electric current.
            • D. A calorimeter is an object used for calorimetry or the process of measuring the heat of chemical reactions or physical changes as well as heat capacity.

            Q125. Which of the following acts as a nucleophile in the reaction of alkyl halide with alcoholic / aqueous ammonia?

            • A. H+
            • B. NH3
            • C. NO2+
            • D. Br-

            Explanation: Since ammonia is nucleophilic, it attacks the electropositive carbon and causes the Br- ion to leave, this allows for the formation of amines as a result of this reaction.

            Why the other options are wrong

              Q126. The liquid in the container has a temperature of 70°C. What will be the temperature on the Kelvin scale?

              • A. 350 K
              • B. 343 K
              • C. 300 K
              • D. 283 K

              Explanation: To convert temperature from celsius to kelvin scale the formula is °C + 273.15 K 70° + 273.15 =343 K.

              Why the other options are wrong
              • A. According to the solution, this is not the correct option.
              • C. According to the solution, this is not the correct option.
              • D. According to the solution, this is not the correct option.

              Q127. The formula which shows the simplest whole number ratio for the atoms of different elements in a compound is:

              • A. Ionic formula
              • B. Structural formula
              • C. Empirical formula
              • D. Molecular formula

              Explanation: The empirical formula of a chemical compound is the simplest positive integer ratio of atoms present in a compound.Ionic formula is the formula of an ionic compound.The structural formula of a chemical compound is a graphic representation of the molecular structure, showing how the atoms are possibly arranged in the real three-dimensional space.A molecular formula consists of the chemical symbols for the constituent elements followed by numeric subscripts describing the number of atoms of each element present in the molecule

              Why the other options are wrong
              • A. lonic formula is the formula of an ionic compound.
              • B. The structural formula of a chemical compound is a graphic representation of the molecular structure, showing how the atoms are possibly arranged in the real three-dimensional space.
              • D. A molecular formula consists of the chemical symbols for the constituent elements followed by numeric subscripts describing the number of atoms of each element present in the molecule.

              Q128. Which one will act as a strong acid?

              • A. Chloroethanoic acid
              • B. Ethanoic acid
              • C. Trichloroethanoic acid
              • D. Dichloroethanoic acid

              Explanation: Chloro groups cause an inductive effect(-I). i.e it is a withdrawing group because it is more electronegative than carbon to which it is attached. -Cl groups pull the bonded electrons from carbon and carbon in turn pulls the electron pair from hydrogen of -COOH group causing more electron deficiency on hydrogen. hydrogen becomes more partially positive hence more acidic. greater the withdrawing effect greater will be polarity and acidity. Since trichloro substituted acetic acid has greater no. of withdrawing groups (3 chloro groups)so it will be more polar and more acidic.

              Why the other options are wrong
              • A. False.Chloro groups cause an inductive effect(-I). i.e it is a withdrawing group because it is more electronegative than carbon to which it is attached. -Cl groups pull the bonded electrons from carbon and carbon in turn pulls the electron pair from hydrogen of -COOH group causing more electron deficiency on hydrogen. hydrogen becomes more partially positive hence more acidic. greater the withdrawing effect greater will be polarity and acidity. Since trichloro substituted acetic acid has greater no. of withdrawing groups (3 chloro groups)so it will be more polar and more acidic.
              • B. False.Chloro groups cause an inductive effect(-I). i.e it is a withdrawing group because it is more electronegative than carbon to which it is attached. -Cl groups pull the bonded electrons from carbon and carbon in turn pulls the electron pair from hydrogen of -COOH group causing more electron deficiency on hydrogen. hydrogen becomes more partially positive hence more acidic. greater the withdrawing effect greater will be polarity and acidity. Since trichloro substituted acetic acid has greater no. of withdrawing groups (3 chloro groups)so it will be more polar and more acidic.
              • D. False.Chloro groups cause an inductive effect(-I). i.e it is a withdrawing group because it is more electronegative than carbon to which it is attached. -Cl groups pull the bonded electrons from carbon and carbon in turn pulls the electron pair from hydrogen of -COOH group causing more electron deficiency on hydrogen. hydrogen becomes more partially positive hence more acidic. greater the withdrawing effect greater will be polarity and acidity. Since trichloro substituted acetic acid has greater no. of withdrawing groups (3 chloro groups)so it will be more polar and more acidic.

              Q129. The shape of [Co(NH3)6]3+ complex is:

              • A. Linear
              • B. Square planar
              • C. Tetrahedral
              • D. Octahedral

              Explanation: The cobalt ion is in +3 oxidation state and has an electronic configuration of 3d6. Six pairs of electrons, one from each ammonia molecule, occupy the six hybrid orbitals, hence the molecule is diamagnetic and octahedral in shape.

              Why the other options are wrong
              • A. As per the explanation, this option is incorrect.
              • B. As per the explanation, this option is incorrect.
              • C. As per the explanation, this option is incorrect.

              Q130. Amino acids react with each other such that -COOH group of one amino acid reacts with the -NH2 group of another amino acid to give a condensed structure as shown below:What is the name of the circled part of this structure?

              • A. Ester linkage
              • B. Peptide linkage
              • C. Carbide linkage
              • D. Azide linkage

              Explanation: A peptide linkage is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O) to form —CONH— .In an ester molecule, the bond connecting the atom doubly bonded to oxygen and the oxygen atom bearing the alkyl or aryl group is called the ester bond or, in biochemistry, ester linkage.

              Why the other options are wrong

                Q131. 3.0 mole of Calcium will contain _ g of Calcium.

                • A. 105 g
                • B. 120 g
                • C. 80 g
                • D. 100 g

                Explanation: Moles of Calcium = 3 Molar mass of Calcium (Ca) = 40 Mass of Calcium in grams = ? Moles = Mass/Molar mass Mass = Moles × Molar mass Mass = 3 x 40 → Mass 120g

                Why the other options are wrong

                  Q132. Which of the following is the correct equation to calculate the relative molecular mass of a gas?

                  • A. M = mPR / VT
                  • B. M = PV / mRT
                  • C. M = mPRT / V
                  • D. M = mRT / PV

                  Explanation: Since PV=NRT where n = m / M PV=MRT / M M=mRT / PV.

                  Why the other options are wrong
                  • A. This is not the correct equation.
                  • B. This is not the correct equation.
                  • C. This is not the correct equation.

                  Q133. Reaction of water with quicklime results in the rise in the temperature of the system. Using the concept of an energy change, indicates the nature of the reaction?

                  • A. Endothermic Reaction
                  • B. Non-Spontaneous Reaction
                  • C. Third Order Reaction
                  • D. Exothermic Reaction

                  Explanation: Calcium oxide reacts with water to form calcium hydroxide, also called slaked lime. Here are the for this reaction: Calcium oxide + water → calcium hydroxide CaO+H2O → Ca(OH)2 A lot of heat is produced in the reaction, which may even cause the water to boil. Hence it is a combination reaction as well as exothermic reaction.

                  Why the other options are wrong
                  • A. Since it is an exothermic reaction, hence this option is incorrect.
                  • B. Since it is an exothermic reaction, hence this option is incorrect.
                  • C. Since it is an exothermic reaction, hence this option is incorrect.

                  Q134. Which one of the following compounds act as a catalyst when alcohols react with carboxylic acids.

                  • A. Pt
                  • B. Conc. HNO3
                  • C. Ni
                  • D. Conc. H2SO4

                  Explanation: When a carboxylic acid is treated with an alcohol and an acid catalyst (Conc H2SO4), an ester is formed (along with water).

                  Why the other options are wrong
                  • A. Option A) Pt: Platinum (Pt) is not typically used as a catalyst in the reaction between alcohols and carboxylic acids.
                  • B. Option B) Conc. HNO3: Concentrated nitric acid (HNO3) is not commonly used as a catalyst in this specific reaction.
                  • C. When alcohols react with carboxylic acids, the compound that acts as a catalyst is concentrated sulfuric acid (option D). Concentrated sulfuric acid helps facilitate the reaction by providing protons (H+) to initiate the reaction between the alcohol and carboxylic acid.

                  Q135. In Period 2 and Period 3 maximum melting point shown by elements:

                  • A. Nitrogen and Phosphorus
                  • B. Neon and Argon
                  • C. Lithium and Sodium
                  • D. Carbon and Silicon

                  Explanation: So in periods two and three, the highest melting point elements tend to be the metal elements with the most delocalized electrons.In period 2, Carbon has the highest melting point, whereas in period 3 silicon has the highest melting point.

                  Why the other options are wrong
                  • A. So in periods two and three, the highest melting point elements tend to be the metal elements with the most delocalized electrons.In period 2, Carbon has the highest melting point, whereas in period 3 silicon has the highest melting point.
                  • B. So in periods two and three, the highest melting point elements tend to be the metal elements with the most delocalized electrons.In period 2, Carbon has the highest melting point, whereas in period 3 silicon has the highest melting point.
                  • C. So in periods two and three, the highest melting point elements tend to be the metal elements with the most delocalized electrons.In period 2, Carbon has the highest melting point, whereas in period 3 silicon has the highest melting point.

                  Q136. Which one of the following reagents is used to distinguish between aldehydes and ketones?

                  • A. Alkaline Iodine
                  • B. Tollen’s Reagent
                  • C. Bromine
                  • D. 2, 4 DNPH

                  Explanation: The Tollens' test is a reaction that is used to distinguish aldehydes from ketones, as aldehydes are able to be oxidized into a carboxylic acid while ketones cannot.Alkaline iodine is used in the iodoform test. When Iodine and sodium hydroxide are added to a compound that contains either a methyl ketone or a secondary alcohol with a methyl group in the alpha position, a pale yellow precipitate of iodoform or triiodomethane is formed. It can be used to identify aldehydes or ketones.A solution of bromine in CH2CL2 is used to either test for unsaturation or to check the ability to be oxidized for example in aldehydes. Bromine solution is naturally orange and when consumed in oxidation, it becomes colourless.2, 4 DNPH is used to detect ketones and aldehydes. A positive test is signalled by the formation of a yellow, orange or red precipitate of the dinitrophenylhydrazone.

                  Why the other options are wrong
                  • A. Alkaline iodine is used in the iodoform test. When iodine and sodium hydroxide are added to a compound that contains either a methyl ketone or a secondary alcohol with a methyl group in the alpha position, a pale yellow precipitate of iodoform or triiodomethane is formed. It can be used to identify aldehydes or ketones.
                  • C. A solution of bromine in CH2CL2 is used to either test for unsaturation or to check the ability to be oxidised for example in aldehydes. Bromine solution is naturally orange and when consumed in oxidation, it becomes colourless.
                  • D. 2, 4 DNPH is used to detect ketones and aldehydes. A positive test is signalled by the formation of a yellow, orange or red precipitate of the dinitrophenylhydrazone.

                  Q137. Gas is enclosed in a container of 20 cm3 with a moving piston. According to the kinetic theory of gases, what will be the effect on freely moving molecules of the gas if the temperature is increased from 20 oC to 100 oC?

                  • A. Pressure will become one half
                  • B. The volume will be increased
                  • C. Temperature has no effect on freely moving molecules
                  • D. Colliding capability of molecule will become lower

                  Explanation: According to Charles's law, the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature, if the pressure remains constant. Since the piston is movable, hence increased temperature causes the volume to be increased.

                  Why the other options are wrong
                  • A. This is not consistent with the kinetic theory. An increase in temperature typically leads to an increase in pressure.
                  • C. This is incorrect. Temperature has a significant effect on the kinetic energy of gas molecules.
                  • D. This is not consistent with the kinetic theory. An increase in temperature typically leads to an increase in the kinetic energy and, consequently, an increase in the colliding capability of gas molecules.

                  Q138. Which of these pollutants is produced by burning of coal and causes acid rain:

                  • A. NO
                  • B. CO2
                  • C. SO2
                  • D. CO

                  Explanation: SO2 is emitted by the burning of fossil fuels — coal, oil, and diesel. SO2 and other sulfur oxides can contribute to acid rain which can harm sensitive ecosystems.Nitrogen oxides are produced in combustion processes, partly from nitrogen compounds in the fuel, but mostly by direct combination of atmospheric oxygen and nitrogen in flames. They also contribute to acid rain.CO2 is a product of combustion reaction and is a greenhouse gas.Carbon monoxide (CO)—a colorless, odorless, tasteless, and toxic air pollutant—is produced in the incomplete combustion of carbon-containing fuels, such as gasoline, natural gas, oil, coal, and wood. It can cause carbon monoxide poisoning.

                  Why the other options are wrong
                  • A. Nitrogen oxides are produced in combustion processes, partly from nitrogen compounds in the fuel, but mostly by direct combination of atmospheric oxygen and nitrogen in flames. They also contribute to acid rain.
                  • B. CO2 is a product of combustion reaction and is a greenhouse gas.
                  • D. Carbon monoxide (CO)—a colourless, odourless, tasteless, and toxic air pollutant is produced in the incomplete combustion of carbon-containing fuels, such as gasoline, natural gas, oil, coal, and wood. It can cause carbon monoxide poisoning.

                  Q139. Role of a catalyst in a chemical reaction is to:

                  • A. Increase rate of a reaction
                  • B. Decrease rate of reaction
                  • C. Decrease yield of a reactant
                  • D. Increase yield of product

                  Explanation: A positive catalyst increase rate of reaction, decreases activation energy, decrease equilibrium time and changes mechanism of reaction.

                  Why the other options are wrong
                  • B. It increases the rate of reaction by lowering activation energy. A catalyst is a chemical substance which helps to increase the rate of the reaction. - It makes the reaction proceed faster by adjusting the activation energy of that reaction or by changing the mechanism of the reaction. - It does not get consumed by itself in the reaction.
                  • C. It only increases rate of reaction.
                  • D. It only increases rate of reaction. A catalyst is a chemical substance which helps to increase the rate of the reaction. - It makes the reaction proceed faster by adjusting the activation energy of that reaction or by changing the mechanism of the reaction. - It does not get consumed by itself in the reaction.

                  Q140. The essential property of a fertilizer is that is should be:

                  • A. Immiscible
                  • B. Highly soluble
                  • C. Insoluble
                  • D. Partially soluble

                  Explanation: There are three essential plant nutrients for healthy growth: nitrogen (N), phosphorous (P), potassium (K). Fertilisers contain one or more of these nutrients and different crops require different proportions of each of the three. For the fertiliser to be effective, it must be soluble so that it can reach the plant’s roots.

                  Why the other options are wrong
                  • A. There are three essential plant nutrients for healthy growth: nitrogen (N), phosphorous (P), potassium (K). Fertilisers contain one or more of these nutrients and different crops require different proportions of each of the three. For the fertiliser to be effective, it must be soluble so that it can reach the plant’s roots.
                  • C. There are three essential plant nutrients for healthy growth: nitrogen (N), phosphorous (P), potassium (K). Fertilisers contain one or more of these nutrients and different crops require different proportions of each of the three. For the fertiliser to be effective, it must be soluble so that it can reach the plant’s roots.
                  • D. There are three essential plant nutrients for healthy growth: nitrogen (N), phosphorous (P), potassium (K). Fertilisers contain one or more of these nutrients and different crops require different proportions of each of the three. For the fertiliser to be effective, it must be soluble so that it can reach the plant’s roots.

                  Q141. Which option shows all the molecules with bond angle 109.5 degrees:

                  • A. CH4 , NH4+ , PH3
                  • B. SiCl4 , H2O , BeCl2
                  • C. SiCl4 , NH4+ , CH4
                  • D. CH4 , CCl4 , NH3

                  Explanation: Since all molecules stated in option C are tetrahedral in shape, where a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. Hence they all have bond angles that are 109.5 degrees.

                  Why the other options are wrong
                  • A. Methane and ammonium ion have bond angles of 109.5o but phosphine has bond angle of 93o
                  • B. SiCl4 has bond angle 109.5o but H2O has 104.5o and BeCl2 has 180o
                  • D. The bond angles in these molecules are influenced by their molecular geometries: Methane (CH₄) -Bond Angle: Approximately 109.5 degrees -The four hydrogen atoms around the central carbon atom are arranged in a tetrahedral shape, leading to bond angles close to 109.5 degrees. Carbon Tetrachloride (CCl₄) -Bond Angle: Approximately 109.5 degrees -Similar to methane, carbon tetrachloride adopts a tetrahedral geometry, resulting in bond angles around 109.5 degrees. Ammonia (NH₃) -Bond Angle: Approximately 107 degrees -The nitrogen atom in ammonia is bonded to three hydrogen atoms, creating a trigonal pyramidal shape. The bond angle is slightly less than the ideal tetrahedral angle due to the presence of a lone pair on nitrogen, which exerts a greater repulsion than bonding pairs. These bond angles are influenced by the arrangement of electron pairs around the central atom and follow the principles of valence shell electron pair repulsion (VSEPR) theory. Therefore this option is not correct.

                  Q142. Down the group acid-base behaviour of metallic oxides of group 2 elements changes to:

                  • A. More basic
                  • B. No change
                  • C. Less basic
                  • D. More acidic

                  Explanation: Group II metal oxides become more basic as you go down the column. As the electronegativities of the metals decrease down the group, hence the change in electronegativity difference between the metal and oxygen increases down the group. The greater the difference in electronegativity the more ionic the metal-oxygen bond becomes. The more ionic the metal-oxygen bond the more basic the oxide is.

                  Why the other options are wrong
                  • B. This option is incorrect as the further you go down the group the acid base character of metallic oxides change towards more basic.
                  • C. This option is incorrect as the further you go down the group the acid base character of metallic oxides change towards more basic.
                  • D. This option is incorrect as the further you go down the group the acid base character of metallic oxides change towards more basic.

                  Q143. Butane molecules can have a maximum number of isomers.

                  • A. 5
                  • B. 3
                  • C. 4
                  • D. 2

                  Explanation: Butane is an alkane with four carbon atoms so the molecular formula is C4H10. It has two isomers; n-butane and isobutane.

                  Why the other options are wrong
                  • A. Butane has 2 isomers therefore it is incorrect.
                  • B. Butane has 2 isomers therefore it is incorrect.
                  • C. Butane has 2 isomers therefore it is incorrect.

                  Q144. Select one which is alcohol.

                  • A. CH3 - CH2 - Br
                  • B. CH3 - O - CH3
                  • C. CH3COOH
                  • D. CH3 - CH2 - OH

                  Explanation: An alcohol is an organic compound that carries at least one hydroxyl functional group (−OH) bound to a saturated carbon atom, hence CH3-CH2-OH is an alcohol. CH3-CH2-Br is an example of an alkyl halide (also known as haloalkanes) which are compounds in which one or more hydrogen atoms in an alkane have been replaced by halogen atoms (fluorine, chlorine, bromine or iodine). Ethers are a class of organic compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula R–O–R′, where R and R′ represent the alkyl or aryl groups. Therefore CH3-O-CH3 is an ether. CH3COOH is a carboxylic acid that is an organic acid which contains a carboxyl group (C(=O)OH) attached to an R-group. The general formula of a carboxylic acid is R–COOH, with R referring to the alkyl, alkenyl, aryl, or other group.

                  Why the other options are wrong
                  • A. CH3-CH2-Br is an example of an alkyl halide (also known as haloalkanes) which are compounds in which one or more hydrogen atoms in an alkane have been replaced by halogen atoms (fluorine, chlorine, bromine or iodine).
                  • B. Ethers are a class of organic compounds that contain an ether group-an oxygen atom connected to two alkyl or aryl groups. They have the general formula R-O-R', where R and R' represent the alkyl or aryl groups. Therefore CH3-O-CH3 is an ether.
                  • C. CH3COOH is a carboxylic acid that is an organic acid which contains a carboxyl group (C(=O)OH) attached to an R- group. The general formula of a carboxylic acid is R-COOH, with R referring to the alkyl, alkenyl, aryl, or other group.

                  Q145. Which is the correct electronic configuration of Chromium (24Cr)?

                  • A. 1s2, 2s2, 3s2, 2p6, 3p6, 4s2, 3d6
                  • B. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d4
                  • C. 1s1, 2s2, 2p6, 3s2, 3p6, 3d6
                  • D. 1s2, 2s2, 2p6, 3s2, 3p6, 4s1, 3d5

                  Explanation: The atomic number of chromium = 24. Cr (Z = 24) = 1s2, 2s2 2p6 3s2 3p6 4s1 3d5

                  Why the other options are wrong
                  • A. This is not the electronic configuration of chromium.
                  • B. This option is also incorrect.
                  • C. This option is also incorrect.

                  Q146. Which one of the following is the structure of Teflon?

                  • A. (-CF2-CF2-)n
                  • B. (-CF2-CCl2-)n
                  • C. (-CH2-CH2-)n
                  • D. (-CF2-CH2-)n

                  Explanation: Teflon is a synthetic polymer containing carbon and fluorine called polytetrafluoroethylene. Its formula is (C2F4)n.

                  Why the other options are wrong
                  • B. The polymer represented by (-CF2-CCl2-)n is commonly known as poly(chlorotrifluoroethylene) or PCTFE. It is a fluoropolymer that exhibits excellent chemical resistance, high thermal stability, and low friction properties. PCTFE is used in various applications such as coatings, films, gaskets, and seals due to its exceptional resistance to chemicals and extreme temperatures.
                  • C. The polymer represented by (-CH2-CH2-)n is commonly known as polyethylene, which is one of the most widely used polymers. Polyethylene has a range of applications due to its excellent physical and chemical properties, including its flexibility, low density, chemical resistance, and electrical insulation properties. It is used in various industries for packaging materials, plastic bags, containers, pipes, and many other everyday products.
                  • D. The polymer represented by (-CF2-CH2-)n can be classified as a fluorinated polymer. The incorporation of fluorine atoms into the polymer chain can impart unique properties such as chemical resistance, low surface energy, and thermal stability. These polymers find applications in various fields, including coatings, lubricants, electrical insulation, and membranes.

                  Q147. Which one of the following enthalpy changes is always exothermic?

                  • A. Enthalpy of combustion
                  • B. Enthalpy of formation
                  • C. Enthalpy of atomization
                  • D. Enthalpy of solution

                  Explanation: Combustion is an oxidation reaction that produces heat, and it is therefore always exothermic. Since these reactions are exothermic so the value for the enthalpy change (ΔH) is always negative

                  Why the other options are wrong
                  • B. The enthalpy of formation is the standard reaction enthalpy for the formation of the compound from its elements (atoms or molecules) in their most stable reference states at the chosen temperature (298.15K).It may be both exothermic & endothermic.
                  • C. Enthalpy of atomization is the change in enthalpy when one mole of bonds is completely broken to obtain atoms in the gas phase. For example: atomization of methane molecule.It is always endothermic.
                  • D. Enthalpies of solution may be either positive or negative - in other words, some ionic substances dissolve endothermically (for example, NaCl); others dissolve exothermically (for example NaOH).

                  Q148. While finding the relative atomic mass, which of the following standard is used to compare the atomic mass of chlorine (35.5 amu):

                  • A. Carbon - 13
                  • B. Neon - 20
                  • C. Carbon - 12
                  • D. Nucleon number

                  Explanation: By international agreement in 1961 for determining atomic masses, carbon-12 a distinct atom of carbon was chosen as standard with its atomic mass 12.00 atomic mass unit. It is defined as 1/12 the mass of an atom of carbon-12. Masses of all other atoms are determined relative to the mass of an atom of carbon 12. Relative atomic mass equals the average mass of all the atoms in an element compared to 1/12 the ​ mass of a carbon-12. Carbon-12 is the standard while measuring the atomic masses. Because no other nuclides other than carbon-12 have exactly whole-number masses in this scale.

                  Why the other options are wrong

                    Q149. Which compound is obtained by the elimination of bromopropane?

                    • A. Propene
                    • B. Ether
                    • C. Aldehyde
                    • D. Ester

                    Explanation: In the elimination reaction involving 2-bromopropane and hydroxide ions. 2-bromopropane is heated under reflux with a concentrated solution of sodium or potassium hydroxide in ethanol. The resulting re-arrangement of the electrons expels the bromine as a bromide ion and produces propene.

                    Why the other options are wrong

                      Q150. Which product is formed by the reaction of carboxylic acid with alcohol?

                      • A. Alkane
                      • B. Ether
                      • C. Aldehyde
                      • D. Ester

                      Explanation: When primary alcohol is treated with a carboxylic acid in the presence of sulphuric acid a compound is formed. This compound has a sweet smell. The compound obtained is called ester. The chemical reaction occurring in the formation of the ester is known as esterification reaction.

                      Why the other options are wrong
                      • A. False.When primary alcohol is treated with a carboxylic acid in the presence of sulphuric acid a compound is formed. This compound has a sweet smell. The compound obtained is called ester. The chemical reaction occurring in the formation of the ester is known as esterification reaction.
                      • B. False.When primary alcohol is treated with a carboxylic acid in the presence of sulphuric acid a compound is formed. This compound has a sweet smell. The compound obtained is called ester. The chemical reaction occurring in the formation of the ester is known as esterification reaction.
                      • C. False.When primary alcohol is treated with a carboxylic acid in the presence of sulphuric acid a compound is formed. This compound has a sweet smell. The compound obtained is called ester. The chemical reaction occurring in the formation of the ester is known as esterification reaction.

                      Q151. In an aqueous solution, amino acids exist in an ionic form as shown below:This ionic form of amino acid is known as:

                      • A. Zwitterion
                      • B. Amphoteric ion
                      • C. Cation
                      • D. Anion

                      Explanation: A zwitterion is a compound with no overall electrical charge, but which contains separate parts which are positively and negatively charged. In an aqueous solution, the carboxyl group can lose a proton (becomes a basic group) and the amino group can accept a proton (becomes acidic) giving rise to the dipolar ion known as Zwitterions.An amphoteric compound is a molecule or ion that can react both as an acid and as a base.

                      Why the other options are wrong
                      • B. An amphoteric compound is a molecule or ion that can react both as an acid and as a base.
                      • C. Cation is a positively charged species.
                      • D. Anion is a negatively charged species.

                      Q152. Reaction mechanism of alkanes with halogens is known as;

                      • A. Propagation
                      • B. Free radical substitution
                      • C. Addition
                      • D. Elimination

                      Explanation: Halogenation of alkanes means the substitution of a halogen atom(s) by the removal of one or more hydrogen atoms in the alkane. The mechanism of halogenations occurs in three steps: chain initiation, chain propagation, and chain termination.The order of reactivity of the halogens towards the halogenations reaction of alkanes as follows: F2> Cl2> Br2> I2.The iodination reaction is reversible as follows:CH4+I2⇌CH3−I+HI.

                      Why the other options are wrong

                        Q153. Why is it necessary to distill aldehyde formed from oxidation of primary alcohol through acidified potassium dichromate (VI) solution or acidified sodium dichromate (VI) solution?

                        • A. Aldehyde formed may be oxidized further to carboxylic acid concerned
                        • B. Aldehyde formed is unstable and decompose back to original precursor i.e. primary alcohol
                        • C. Aldehyde may be oxidised further to a ketone
                        • D. Aldehyde formed may react with primary alcohol, the original reactant.

                        Explanation: Oxidation of alcohols to aldehydes is partial oxidation, if aldehydes are further oxidized they form carboxylic acids. Therefore, the conditions required for making aldehydes are heat and distillation.

                        Why the other options are wrong
                        • B. Oxidation of alcohols to aldehydes is partial oxidation, if aldehydes are further oxidized they form carboxylic acids. Therefore, the conditions required for making aldehydes are heat and distillation.
                        • C. Oxidation of alcohols to aldehydes is partial oxidation, if aldehydes are further oxidized they form carboxylic acids. Therefore, the conditions required for making aldehydes are heat and distillation.
                        • D. Oxidation of alcohols to aldehydes is partial oxidation, if aldehydes are further oxidized they form carboxylic acids. Therefore, the conditions required for making aldehydes are heat and distillation.

                        Q154. Electron affinity of the atom is the energy released when:

                        • A. Covalent bond of molecule is broken.
                        • B. Electron is added to gaseous atom.
                        • C. Electron is removed from gaseous atom.
                        • D. Covalent bond is formed between the atoms.

                        Explanation: The electron affinity (Eea) of an atom or molecule is defined as the amount of energy released when an electron is attached to a neutral atom or molecule in the gaseous state to form a negative ion.

                        Why the other options are wrong
                        • A. Electron affinity of an atom is the energy released when an electron is added to a neutral atom to form a negative ion (anion). It is a measure of how much the atom "likes" to gain an electron. Therefore this option is not correct.
                        • C. Electron affinity of an atom is the energy released when an electron is added to a neutral atom to form a negative ion (anion). It is a measure of how much the atom "likes" to gain an electron. Therefore this option is not correct.
                        • D. Electron affinity of an atom is the energy released when an electron is added to a neutral atom to form a negative ion (anion). It is a measure of how much the atom "likes" to gain an electron. Therefore this option is not correct.

                        Q155. Which mechanism of reactions is shown by carbonyl compounds?

                        • A. Electrophilic addition
                        • B. Electrophilic substitution
                        • C. Free radical substitution
                        • D. Nucleophilic addition

                        Explanation: The main reactions of the carbonyl group are nucleophilic additions to the carbon‐oxygen double bond. This addition consists of adding a nucleophile and a hydrogen across the carbon‐oxygen double bond. An electrophilic addition reaction is an addition reaction where, in a chemical compound, a π bond is broken and two new σ bonds are formed. The substrate of an electrophilic addition reaction must have a double bond or triple bond. Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a functional group in a compound. Free radicals are atoms or groups of atoms which have a single unpaired electron. A free radical substitution reaction is one involving these radicals. Free radicals are formed if a bond splits evenly - each atom getting one of the two electrons. The name given to this is homolytic fission.

                        Why the other options are wrong
                        • A. An electrophilic addition reaction is an addition reaction where, in a chemical compound, a π bond is broken and two new o bonds are formed. The substrate of an electrophilic addition reaction must have a double bond or triple bond.
                        • B. Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a functional group in a compound.
                        • C. Free radicals are atoms or groups of atoms which have a single unpaired electron. A free radical substitution reaction is one involving these radicals. Free radicals are formed if a bond splits evenly - each atom getting one of the two electrons. The name given to this is homolytic fission.

                        Q156. Which of the following compounds is solid at room temperature?

                        • A. Ethanol
                        • B. Butane
                        • C. Methanol
                        • D. Phenol

                        Explanation: Phenols occur as white solids at room temperature and may be highly toxic and caustic.

                        Why the other options are wrong
                        • A. At room temperature ethanol and methanol are both liquid.
                        • B. At room temperature ethanol and methanol are both liquid.
                        • C. Butane is a gas at room temperature and atmospheric pressure.

                        Q157. Halogens are being used as fire extinguishers, mild antiseptic CFCs and many other organic chemicals, Which of the following halogen is used to kill the bacteria in drinking water.

                        • A. Bromine
                        • B. Fluorine
                        • C. Chlorine
                        • D. Iodine

                        Explanation: One of the easiest and cost effective way to clean water is to add some amount of chlorine into it. But if chlorine is added in excess then the water becomes unfit for consumption. So, when chlorinated water from treatment plants is disposed into rivers etc then it becomes harmful for aquatic species as excess of chlorinated water can lead to death of living beings. Hence, chlorine must be removed from water before releasing the water from water treatment plants into rivers, lakes or oceans.

                        Why the other options are wrong
                        • A. Bromine is not typically used for disinfection of drinking water. It is more commonly employed in hot tubs and swimming pools as a disinfectant.
                        • B. Fluorine gas is not used for disinfection of drinking water. Fluoride, an ion derived from fluorine, is sometimes added to drinking water, but for dental health rather than as a disinfectant.
                        • D. Iodine is used for disinfection, but it is less common in the treatment of drinking water. It is sometimes used in camping or emergency situations where other disinfection methods are not readily available.

                        Q158. Which of the following acts as an electrophile in the electrophilic substitution of benzene with bromine?

                        • A. Br+
                        • B. FeCl4+
                        • C. Fe2+
                        • D. Fe3+

                        Explanation: Benzene reacts with bromine in an electrophilic substitution reaction, but only in the presence of a catalyst to yield bromobenzene. As a bromine molecule approaches the benzene ring, the delocalised electrons in the ring repel electrons in the bromine-bromine bond. It is the slightly positive end of the bromine molecule which acts as the electrophile. The presence of the aluminium chloride helps this polarisation.

                        Why the other options are wrong
                        • B. FeCl4- is an electrophile in acylation of benzene.Therefore it is incorrect.
                        • C. It is not an electrophile.Therefore this option is incorrect.
                        • D. Fe3+ is not an electrophile in this reaction.Therefore it is incorrect.

                        Q159. According to Lowry - Bronsted Acid & Base Concept, H2O is:

                        • A. An acid
                        • B. A base
                        • C. An amphoteric species
                        • D. A salt

                        Explanation: Water is an example of an amphiprotic substance. This means it is able to donate a proton or accept a proton. The Bronsted/Lowry theory defines an acid or base by how they behave in a chemical reaction. Depending on what water reacts with it can act as an acid (proton donor) or a base (proton acceptor).

                        Why the other options are wrong

                          Q160. Which one of the following compounds is known as tertiary alcohol?

                          • A. 1 - Propanol
                          • B. 2- methyl - 2- propanol
                          • C. 2- methyl - 1- propanol
                          • D. 2 - propanol

                          Explanation: 2-methyl-2-propanol / tert-Butyl alcohol, also called tert-butanol or t-butanol, is the simplest tertiary alcohol, with a formula of (CH₃)₃COH.

                          Why the other options are wrong
                          • A. This is primary alcohol.
                          • C. Isobutanol, also known as iso-butyl alcohol or 2-methylpropanol, belongs to the class of organic compounds known as primary alcohols.
                          • D. 2-Propanol, or isopropyl alcohol, is a three-carbon alcohol with the OH group on the middle carbon. Isopropyl alcohol is a secondary alcohol

                          Q161. Which of the following molecules has the largest number of shared pairs of electrons?

                          • A. C2H4
                          • B. N2
                          • C. CO2
                          • D. NH3

                          Explanation: C2H4 has the largest number of shared electrons as it has 12 valence electrons in total which are all part of a shared pair (4 electrons between the two central carbons and 2 electrons each between 4 carbon-Hydrogen bonds).N2 has 3 shared pairs of electron (6 electrons in total)CO2 has 4 shared pairs of electrons (8 electrons in total).NH3 has 3 shared pairs of electrons. (6 electrons in total)

                          Why the other options are wrong
                          • B. N2 has 3 shared pairs of electron (6 electrons in total).
                          • C. CO2 has 4 shared pairs of electrons (8 electrons in total).
                          • D. NH3 has 3 shared pairs of electrons. (6 electrons in total).

                          Q162. Which of the following gas, when ignited, burns with a blue flame and is not very soluble in water?

                          • A. O2
                          • B. CO2
                          • C. N2
                          • D. He

                          Explanation: Firstly we should be clear that each gas has a specific type of flame depending on the nature of combustion and the products formed and so does all these gases which are given in the option. Nitrogen when ignited in the presence of oxygen it forms various oxides of nitrogen like NO, NO2 and burns with a blue flame.

                          Why the other options are wrong
                          • A. O2 does not burn with blue flame. It is partially soluble in water.
                          • B. CO2 burns with blue flame but is highly soluble in water.
                          • D. He burns with pinkish orange flame and is insoluble in water.

                          Q163. The dilute solution of _ is called vinegar.

                          • A. Formic acid
                          • B. Oxalic acid
                          • C. Benzoic acid
                          • D. Acetic acid

                          Explanation: A dilute (approximately 5 percent by volume) solution of acetic acid produced by fermentation and oxidation of natural carbohydrates is called vinegar.

                          Why the other options are wrong

                            Q164. Percentage of nitrogen by volume in air is:

                            • A. 78%
                            • B. 50%
                            • C. 20%
                            • D. 98%

                            Explanation: By volume, the dry air in Earth's atmosphere is about 78.08 percent nitrogen, 20.95 percent oxygen, and 0.93 percent argon. A brew of trace gases accounts for the other approximately 0.04 percent, including the greenhouse gases carbon dioxide, methane, nitrous oxide and ozone.

                            Why the other options are wrong
                            • B. As per the explanation, this is not the correct option.
                            • C. As per the explanation, this is not the correct option.
                            • D. As per the explanation, this is not the correct option.

                            Q165. Bromination of alkene is shown in the following reaction. This reaction is used for:

                            • A. Detection of ketones
                            • B. Detection of double bond
                            • C. Identification of Primary and Secondary alcohols
                            • D. Detection of Aldehydes

                            Explanation: The electrophilic addition of bromine to Alkenes in the cold with pure liquid bromine, or with a solution of bromine in an organic solvent like tetrachloromethane allows for a testing of double bonds. Presence of double bonds causes the bromine to turn from red to colourless.

                            Why the other options are wrong
                            • A. This reaction is used for detection of unsaturation.Therefore this option is incorrect.
                            • C. This reaction is used for detection of unsaturation of double bond.Therefore this option is incorrect.
                            • D. This reaction is used for detection of unsaturation of double bond.Therefore this option is incorrect.

                            Q166. The correct order of increasing reactivity of the following alkyl halides, (I) CH3​CH2​CH2​Cl(II) CH3​CH2​CH2​CH2​Br(III) (CH3​)2​C(Cl)CH2​CH3​(IV) CH3​CH2​CH(Br)CH3​ Towards SN​2 displacement is:

                            • A. I < II < III < IV
                            • B. III < I < IV < II
                            • C. III < I < II < IV
                            • D. II < IV < I < III
                            • E. I < III < II < IV

                            Explanation: The reactivity of alkyl halides towards SN2 depends on:(i) Degree of C-atoms Reactivity Order:1°>2°>3°(ii)More good the leaving group more will be reactivity of alkyl halide in SN2 since order of leaving group is I>Br>Cl>F Hence, correct order is: III<I<IV<||. Hence option B is correct.

                            Why the other options are wrong

                              Q167. Which of the following would react with ozone in the atmosphere?

                              • A. F*
                              • B. O2
                              • C. O*
                              • D. Cl*

                              Explanation: Chlorine and bromine atoms are also known as free radicals. Other free radicals in the stratosphere can also remove ozone. The chlorine atoms react with ozone to produce chlorine oxide and O2 molecules. The chlorine oxide molecule is also very reactive and can react with oxygen atoms to regenerate the chlorine atom, hence catalysing the destruction of the ozone layer.

                              Why the other options are wrong
                              • A. Fluorine radicals are highly reactive but are not typically found in significant quantities in the Earth's atmosphere. Fluorine is a reactive element, but its reactivity with ozone is not a common atmospheric process.
                              • B. Oxygen molecules (O2) are not reactive with ozone (O3) under normal atmospheric conditions. Ozone is a less stable allotrope of oxygen and can react with certain substances, but oxygen itself is not one of them.
                              • C. Oxygen radicals (O*) can react with ozone, but they are not as common in the atmosphere as other reactive species. Oxygen radicals can be formed in certain atmospheric processes, but they are not a primary reactant in ozone depletion reactions.

                              Q168. A 5 watt LED bulb converts 80% of the power into light photons wavelength 660 nm. What is the number of photons emitted from the bulb in one second.

                              • A. 5.8 x 1034
                              • B. 7.5 x 1018
                              • C. 6.6 x 107
                              • D. 1.3 x 1019

                              Explanation: Photon energy formula: E=hc/λ , where h is planck's constant λ =660nm c= 3*108 m/s h= 6.626 × 10-34 Js E=6.626*10-34 * 3*108 / 660*10-9 (Js*m/s/m = J) E=3.01*10-19J(per photon) Total energy= 1sec*5watt*80/100(efficiency) = 4 ws = 4J No. of photons = Total energy/E = 4J/3.01*10-19J = 1.3*1019

                              Why the other options are wrong
                              • A. Photon energy formula: E=hc/^, where h is planck's constant, λ =660nmc= 3*108 m/sh= 6.626 x10-34 Js.E=6.626*10-34 ×3*108 ÷ 660*10-9(Js*m/s/m = J)E=3.01*10-19J(per photon)Total energy= 1 sec×5 watt×80/100(efficiency) =4 ws = 4JNo. of photons = Total energy/E= 4J/3.01*10-19J = 1.3*1019.
                              • B. Photon energy formula: E=hc/^, where h is planck's constant, λ =660nmc= 3*108 m/sh= 6.626 x10-34 Js.E=6.626*10-34 ×3*108 ÷ 660*10-9(Js*m/s/m = J)E=3.01*10-19J(per photon)Total energy= 1 sec×5 watt×80/100(efficiency) =4 ws = 4JNo. of photons = Total energy/E= 4J/3.01*10-19J = 1.3*1019.
                              • C. Photon energy formula: E=hc/^, where h is planck's constant, λ =660nmc= 3*108 m/sh= 6.626 x10-34 Js.E=6.626*10-34 ×3*108 ÷ 660*10-9(Js*m/s/m = J)E=3.01*10-19J(per photon)Total energy= 1 sec×5 watt×80/100(efficiency) =4 ws = 4JNo. of photons = Total energy/E= 4J/3.01*10-19J = 1.3*1019.

                              Q169. If Cv = 5/2 R, Cp will be:

                              • A. 2 / 5 R
                              • B. 2 / 7 R
                              • C. 5 / 2 R
                              • D. 7 / 2 R

                              Explanation: Since Cp - Cv = Rhence , X - 5/2 R = RX = 7/2 R

                              Why the other options are wrong
                              • A. This option is incorrect. The specific heat at constant pressure (Cp) is related to the specific heat at constant volume (Cv) by the equation: Cp=Cv+R for an ideal gas. Since Cv= 5/2R, adding R to 5/2R yields 7/2R, not 2/5R.
                              • B. This option is incorrect. Similar to option A,2/7R is not the correct expression for Cp. The specific heat at constant pressure is always greater than the specific heat at constant volume for an ideal gas due to the energy required to work against the external pressure during expansion.
                              • C. This option is incorrect because it presents Cp as being equal to Cv. However, Cp is always greater than Cv for an ideal gas due to the energy required to do work against the external pressure during expansion.

                              Q170. The rate at which work is being done is called:

                              • A. Power
                              • B. Energy
                              • C. Density
                              • D. Force

                              Explanation: The rate at which work is done is called power. It is expressed as the amount of work per unit of time.

                              Why the other options are wrong
                              • B. In physics, energy is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light.
                              • C. Density is the measurement of how tightly a material is packed together. It is defined as the mass per unit volume.
                              • D. A force can cause an object with mass to change its velocity, i.e., to accelerate.

                              Q171. What is the instantaneous power dissipated through a resistor of resistance 10 ohm if it is connected to an AC source of frequency 15 Hz at 1/180 sec if peak value is 20 V?

                              • A. 10 W
                              • B. 100 W
                              • C. 40 W
                              • D. Cannot be determined

                              Explanation: UsingVo = V sin(2𝜋ft) = 20 x sin (2𝜋 x 15 x 1/180) = 10 VUsingP = v2/ R = 102 / 10 = 10 W

                              Why the other options are wrong

                                Q172. A signal of -80 mV is applied to the inverting terminal of the amplifier while the non-inverting terminal is grounded. The gain of the amplifier is 25 using Rin(R1) equal to 3 ohms and Rf(R2) equal to 75 Ohms. What would be the value of the output signal?

                                • A. 200 mV
                                • B. -3 V
                                • C. 2 V
                                • D. 3 V

                                Explanation: Since Gain = 25Vout = Vin * Gain = -80mv * 25 = -2000 mv = -2V = 2V**** since a positive-going voltage at the inverting terminal gives a negative-going output voltage, hence the answer is positive 2V.

                                Why the other options are wrong
                                • A. This option suggests that the output signal would be 200mV.However, based on the given gain of the amplifier (25) and the input signal (-80mV), the output signal will be greater than 200mV.Therefore, option A) 200mV is incorrect.
                                • B. This option suggests that the output signal would be -3V.However, based on the given gain of the amplifier (25) and the input signal (-80mV), the output signal will be a positive voltage.Therefore, option B) -3V is incorrect.
                                • D. This option suggests that the output signal would be 3V.However, based on the given gain of the amplifier (25) and the input signal (-80mV), the output signal will be less than 3V.Therefore, option D) 3V is incorrect.

                                Q173. When the frequency of the applied force becomes equal to one of natural frequencies of body then the body oscillates with maximum displacement this phenomenon is called:

                                • A. Heating
                                • B. Resonance
                                • C. Reverberation
                                • D. Damping

                                Explanation: Resonance describes the phenomenon of increased amplitude that occurs when the frequency of a periodically applied force is equal or close to a natural frequency of the system on which it acts.

                                Why the other options are wrong
                                • A. Heating refers to the process of increasing the temperature of an object or substance. It occurs when energy is transferred to the object, typically resulting in an increase in kinetic energy of its particles, leading to higher temperature. In the context of oscillations and resonance, heating may occur due to friction or other dissipative processes that convert mechanical energy into thermal energy.
                                • C. Reverberation refers to the persistence of sound in an enclosed space due to repeated reflections off surfaces. It is commonly experienced in rooms with hard and reflective surfaces, such as concert halls or empty rooms. Reverberation can affect the clarity and quality of sound, and it is often controlled or mitigated in acoustic design to optimize the acoustic environment.
                                • D. Damping is the process by which energy is dissipated or removed from a vibrating system, causing its amplitude to decrease over time. Damping can occur due to various factors such as friction, air resistance, or energy transfer to other modes of vibration. It is essential for controlling oscillations and preventing excessive vibration in mechanical systems. In the context of resonance, damping is necessary to prevent the system from oscillating uncontrollably at resonance frequencies.

                                Q174. Force is a derived quantity, its derived unit can be expressed in terms of the base units as:

                                • A. Kgms-2
                                • B. Kgcms-2
                                • C. Kgm2s2
                                • D. Kgms2

                                Explanation: The following is the solution:Since F=ma ,where m: mass in kg,a: acceleration in m/s²,F = Kgms-2 = Newton

                                Why the other options are wrong
                                • B. Incorrect as per the formula
                                • C. Incorrect as per the formula
                                • D. Incorrect as per the formula

                                Q175. E/m of an electron is given by the relationship.

                                • A. e/m2(VB2r2)
                                • B. e/m=(V/Br)2
                                • C. e/m=V.r/B
                                • D. e/m=V/Br

                                Explanation: When an electron enters a region in which there is a uniform magnetic field, B, perpendicular to the velocity, v, of the electron (Caution: The capital letter V will be used below to represent voltage. Don't confuse v with V!), the electron experiences a force, F, with a magnitude given by the following equation.F = evB The force is perpendicular to both v and B and its direction can be found by using the right-hand rule. The force will cause the electron to move in a circular orbit with radius r (uniform circular motion). Equating this force to the mass times the centripetal acceleration, we have the equation below.evB = mv2/rSolving Eq. 2 for e/m, we get the following equation.e/m = v/Br

                                Why the other options are wrong

                                  Q176. Lenz’s law in electromagnetic induction is the direct consequence of the principle of conservation of:

                                  • A. Energy
                                  • B. Charge
                                  • C. Momentum
                                  • D. Mass

                                  Explanation: Lenz’s law is used to determine the direction of the induced current by a change in magnetic field. This direction of the induced current always opposes the direction of the magnetic field which produced it. Complete step by step answer: Lenz’s law states that the direction of an induced current by a changing magnetic field is such that the magnetic field created by the induced current opposes that change responsible for its production. This means, a change in magnetic field (B1) produces an induced current and the induce current also generates some magnetic field (B2) which is different from the initial magnetic field (B1). Now, the generated magnetic field (B2) by the induced current opposes the initial changing magnetic field (B1). Consider a magnet and a coil, such that the magnet is approaching towards the coil. When the north pole of a magnet is moved towards a coil, the face of the coil near to the magnet behaves like a north pole and tries to repel the approaching North Pole. To do this, the coil generates an anticlockwise current in itself. Here, we can see that electrical energy is not generated just by moving the magnet towards the coil. There is an opposite for the change in flux. Hence we can say that Lenz’s law is a consequence of conservation of energy. Thus, the right answer is Option A; Lenz’s law is a consequence of law of conservation of energy.

                                  Why the other options are wrong

                                    Q177. Which material will follow the below stress-strain curve?

                                    • A. Copper
                                    • B. Iron
                                    • C. Lead
                                    • D. Glass

                                    Explanation: A stress-strain curve is a graphical way to show the reaction of a material when a load is applied. It shows a comparison between stress and strain.Brittle materials, which comprise cast iron, glass, and stone, are characterized by the fact that rupture occurs without any noticeable prior change in the rate of elongation. Thus, for brittle materials, there is no difference between the ultimate strength and the breaking strength.

                                    Why the other options are wrong
                                    • A. A stress-strain curve is a graphical way to show the reaction of a material when a load is applied. It shows a comparison between stress and strain.Brittle materials, which comprise cast iron, glass, and stone, are characterized by the fact that rupture occurs without any noticeable prior change in the rate of elongation. Thus, for brittle materials, there is no difference between the ultimate strength and the breaking strength.Hence this option is incorrect since the given graph represents brittle solids only.
                                    • B. A stress-strain curve is a graphical way to show the reaction of a material when a load is applied. It shows a comparison between stress and strain.Brittle materials, which comprise cast iron, glass, and stone, are characterized by the fact that rupture occurs without any noticeable prior change in the rate of elongation. Thus, for brittle materials, there is no difference between the ultimate strength and the breaking strength.Hence this option is incorrect since the given graph represents brittle solids only.
                                    • C. A stress-strain curve is a graphical way to show the reaction of a material when a load is applied. It shows a comparison between stress and strain.Brittle materials, which comprise cast iron, glass, and stone, are characterized by the fact that rupture occurs without any noticeable prior change in the rate of elongation. Thus, for brittle materials, there is no difference between the ultimate strength and the breaking strength.Hence this option is incorrect since the given graph represents brittle solids only.

                                    Q178. A wheel starts rotating from the result with an angular acceleration of 2 rads-2 till its angular speed becomes 6 rad/s. The angular displacement of the wheel will be equal to:

                                    • A. 4 rad
                                    • B. 9 rad
                                    • C. 12 rad
                                    • D. 7 rad

                                    Explanation: V = u + at6 = 0 + 2tt = 3 secondsØ = ut + 1/2at2Ø = 0 + 1/2 • 2 • 3²Ø = 9 radian.

                                    Why the other options are wrong
                                    • A. It is incorrect as per the given formula.
                                    • C. It is incorrect as per the given formula.
                                    • D. It is incorrect as per the given formula.

                                    Q179. Coulomb's law is given by the formula:F=kq1 q2 / r2The magnitude of k having the unit of Nm2 C-2 for free space is equal to:

                                    • A. 9 x 107
                                    • B. 6 x 107
                                    • C. 10 x 109
                                    • D. 9 x 109

                                    Explanation: The Coulomb constant, the electric force constant, or the electrostatic constant (denoted ke, k or K) is a proportionality constant in electrostatics equations. In SI units it is equal to 8.9875517923(14)×109 (9*109)kg⋅m3⋅s−2⋅C−2

                                    Why the other options are wrong
                                    • A. Incorrect as per formula
                                    • B. Incorrect as per formula
                                    • C. Incorrect as per formula

                                    Q180. Simple Harmonic Motion of a body is described by which statements mentioned below:K: K.E is maximum when displacement x = 0L: P.E is maximum when x = 0M: P.E is maximum when x = ± x0

                                    • A. K and L
                                    • B. K and M
                                    • C. K, L and M
                                    • D. L and M

                                    Explanation: Option A is incorrect because the statement about potential energy (P.E) is incorrect.Option B is correct as both statements about kinetic energy (K.E) and potential energy (P.E) are true.Option C is incorrect because one of the statements about potential energy (P.E) is incorrect.Option D is incorrect because it contains two statements about potential energy (P.E), and one of them is incorrect.

                                    Why the other options are wrong
                                    • A. This option combines both correct and incorrect statements. While the statement about kinetic energy (K.E) is correct (K.E is maximum when displacement x = 0), the statement about potential energy (P.E) is incorrect. The potential energy is maximum at the extreme positions (x = ± x0), not when the displacement is zero.
                                    • C. This option combines both correct and incorrect statements. The statement about kinetic energy (K.E) being maximum when displacement x = 0 is true. However, the statement about potential energy (P.E) being maximum when x = ± x0 is correct, not when x = 0. The statement about P.E being maximum when x = 0 is incorrect since the potential energy is actually minimum (zero) at the equilibrium position.
                                    • D. This option contains two statements about potential energy (P.E). While the statement about P.E being maximum when x = ± x0 is correct, the statement about P.E being maximum when x = 0 is incorrect. As explained earlier, the potential energy is minimum (zero) at the equilibrium position (x = 0).

                                    Q181. Which of the following gives the relationship between linear velocity and angular velocity?

                                    • A. v = rω
                                    • B. v = rθ
                                    • C. v=sω
                                    • D. v=sθ

                                    Explanation: The greater the rotation angle in a given amount of time, the greater the angular velocity. Angular velocity (w) is analogous to linear velocity (v).We can write the relationship between linear velocity and angular velocity in two different ways: v=rw or w=v/r.The difference between these two quantities must also be known;

                                    Why the other options are wrong
                                    • B. It is incorrect as per the given explanation.
                                    • C. It is incorrect as per the given explanation.
                                    • D. It is incorrect as per the given explanation.

                                    Q182. A torch is rated 2.2 V 0.25 A. Calculate the charge passing through the bulb in one second and energy transferred by the passage of each coulomb of charge.

                                    • A. 2.5 C and 0.55 J
                                    • B. 0.25 C and 0.55 J
                                    • C. 0.25 C and 2.2 V
                                    • D. 2.25 V and 0.55 J

                                    Explanation: Q= I*t = 0.25*1 = 0.25 CV = U/q U= V*q = 2.2V*0.25C = 0.55J

                                    Why the other options are wrong
                                    • A. This option is incorrect as per the formula and calculations
                                    • C. This option is incorrect as per the formula and calculations
                                    • D. This option is incorrect as per the formula and calculations

                                    Q183. Energy consumed by 60 watt bulb in 2 minutes is equal to:

                                    • A. 7.2 kilo joules
                                    • B. 720 joules
                                    • C. 120 joules
                                    • D. 72000 joules

                                    Explanation: Power=Energy/time Energy=power ×time 60 watt×120 sec =7200 J =7.2 kilo J.

                                    Why the other options are wrong
                                    • B. Incorrect as per the formula
                                    • C. Incorrect as per the formula
                                    • D. Incorrect as per the formula

                                    Q184. If one mole of an ideal gas is heated at constant pressure, then the first law of thermodynamics can be written as:

                                    • A. CpΔT = CvΔT + PΔV
                                    • B. CvΔT = CpΔT + PΔV
                                    • C. CpΔT = CvΔT + VΔP
                                    • D. ΔCpT = ΔCvT + PΔV

                                    Explanation: Heat supplied to the gas at constant pressure isΔQ=nCPΔTChange in internal energy,ΔU=nCVΔTChange in work done,ΔW = PΔVAccording to the first law of thermodynamicsΔQ=ΔU+ΔWnCPΔT= nCVΔT + PΔV

                                    Why the other options are wrong
                                    • B. This equation incorrectly represents the first law of thermodynamics. It seems to mix up the roles of Cp and Cv, and it incorrectly includes PΔV on both sides of the equation. This option is incorrect.
                                    • C. This equation introduces the VΔP term, which is inconsistent with the first law of thermodynamics for an ideal gas heated at constant pressure. The correct term should involve PΔV instead of VΔP. This option is incorrect.
                                    • D. This equation introduces changes in heat capacities (ΔCp and ΔCv) which is not relevant to the first law of thermodynamics for an ideal gas heated at constant pressure. It also incorrectly represents the relationship between heat capacities and the change in internal energy or enthalpy. This option is incorrect.

                                    Q185. The de Broglie wavelength of an electron travelling with a speed of 1.0 x 107m/s is equal to, (h=6.6 x 10-34 Js and me= 9.1 x 10-31 kg)

                                    • A. 7.3 x 1011 m
                                    • B. 7.3 x 108 m
                                    • C. 7.3 x 10-11 m
                                    • D. 7.3 x 10-13 m

                                    Explanation: De broglie wavelength of any particle: λ = h/p and p = mv ∴λ = h/mvλ = 6.6* 10-34 / (9.1*10-31*1.0*107)λ= 7.2527473e-11m

                                    Why the other options are wrong
                                    • A. De broglie wavelength of any particle: λ = h/p and p = mv ∴λ = h/mvλ = 6.6* 10-34 / (9.1*10-31*1.0*107)λ= 7.2527473e-11m
                                    • B. De broglie wavelength of any particle: λ = h/p and p = mv ∴λ = h/mvλ = 6.6* 10-34 / (9.1*10-31*1.0*107)λ= 7.2527473e-11m
                                    • D. De broglie wavelength of any particle: λ = h/p and p = mv ∴λ = h/mvλ = 6.6* 10-34 / (9.1*10-31*1.0*107)λ= 7.2527473e-11m

                                    Q186. Find the mean translational kinetic energy of ideal hydrogen gas at 17 degrees Celsius.

                                    • A. 6.21 x 10-21 J
                                    • B. 5 x 10-21J
                                    • C. 6.21 x 10-12 J
                                    • D. 6 x 10-21 J

                                    Explanation: Following is the correct solution:

                                    Why the other options are wrong
                                    • B. This option is incorrect. It's significantly lower than the correct value obtained using the formula for mean translational kinetic energy. This could be a distractor value.
                                    • C. This option is incorrect. It's several orders of magnitude higher than the correct value. This suggests a calculation error or a misunderstanding of the formula for mean translational kinetic energy.
                                    • D. This option is incorrect. While it's close to the correct value, it's not accurate. It's important to calculate the value precisely using the correct formula to ensure accuracy.

                                    Q187. Calculate the activity (decaying atom per unit time) of radioactive strontium - 90 having 6.7 x 1021 atoms at t = 0. Decay constant of strontium - 90 is 8.3 x 10-10 s-1

                                    • A. 8.01 x 1010 Bq
                                    • B. 5.6 x 1011 s-1
                                    • C. 5.6 x 1012 Bq
                                    • D. 12 x 1011 Bq

                                    Explanation: A=λN0e(-λt)where λ = decay constantA= (8.3*10-10)* (6.7*1021) * (e) (-8.3 x 10-10*0) = 5.561 *1012

                                    Why the other options are wrong

                                      Q188. If the time period of the oscillation is 20 micro-sec, then what will be the frequency of that oscillating body?

                                      • A. 5000 Hz
                                      • B. 50000 Hz
                                      • C. 20000 Hz
                                      • D. 1000 Hz

                                      Explanation: T=1/FT=1/20×10-6F = 50000 Hz.

                                      Why the other options are wrong
                                      • A. This option suggests that the frequency of the oscillating body is 5000 Hz. However, this is not correct.The frequency (f) of an oscillating body is defined as the reciprocal of its time period (T). In this case, if the time period is 20 microseconds (20×10−6seconds), then the frequency is 1/20×10−6=50,000Hz, not 5000 Hz.
                                      • C. This option suggests that the frequency of the oscillating body is 20000 Hz. However, this is not correct.The frequency (f) of an oscillating body is defined as the reciprocal of its time period (T). In this case, if the time period is 20 microseconds (20×10−6seconds), then the frequency is 1/20×10−6=50,000Hz, not 20000 Hz.
                                      • D. This option suggests that the frequency of the oscillating body is 1000 Hz. However, this is not correct.The frequency (f) of an oscillating body is defined as the reciprocal of its time period (T). In this case, if the time period is 20 microseconds (20×10−6seconds), then the frequency is 1/20×10−6=50,000Hz, not 1000 Hz.

                                      Q189. In photo-emission from a metal, if light of λ is replaced by light of wavelength λ / 4 , the maximum kinetic energy of the photoelectrons.

                                      • A. Decreases by an amount equal to half of an incident photon of wavelength λ
                                      • B. Increases by an amount equal to four times energy of an incident photon of wavelength λ
                                      • C. Increases by an amount equal to the work function of the metal
                                      • D. Decreases by an amount equal to the energy of an incident photon of wavelength λ

                                      Explanation: The maximum kinetic energy KEe of ejected electrons (photoelectrons) is given by KEe=hf−BE , where hf is the photon energy and BE is the binding energy (or work function) of the electron to the particular material. Since f = v/ λ when λ is replaced by λ/4 , f increases by 4 times and hence the energy of incident photons increases by 4 times.

                                      Why the other options are wrong
                                      • A. When the wavelength of the incident light is decreased to λ/4 the energy of each photon increases. The energy of a photon is directly proportional to its frequency and inversely proportional to its wavelength. So, if the wavelength decreases to λ/4 the energy of each photon increases by a factor of 4. When a photoelectron is emitted, it gains energy from absorbing a photon. Since each photon now carries four times the energy compared to before, the photoelectron would gain four times the energy compared to when the wavelength was λ Thus, the correct choice would involve an increase in kinetic energy, not a decrease.
                                      • C. The work function represents the minimum energy required to eject an electron from the metal surface. However, changing the wavelength of the incident light doesn't change the work function of the metal. Therefore, this option doesn't accurately describe the effect of changing the wavelength of the incident light.
                                      • D. This choice contradicts the fact that decreasing the wavelength of the incident light increases the energy of each photon, which in turn increases the kinetic energy of the emitted photoelectrons. So, this option is not correct.

                                      Q190. A cyclist is travelling at 15 ms-1, she applies brakes so that she doesn't collide with the wall in front of her at a distance of 18 m. Calculate the magnitude of deceleration.

                                      • A. 6.3 ms-1
                                      • B. 5.3 ms-1
                                      • C. 13 ms-1
                                      • D. 12.5 ms-1

                                      Explanation: Initial velocity, u=15m/sFinal velocity, v=0m/sDistance, s=18mAcceleration, a=?Using relation, v2 −u2 =2as02 −(15)2 =2a×18−225=36aa= 36 −225 ​ =−6.25m/s2So, deceleration is 6.25m/s2 which is equal 6.3m/s2

                                      Why the other options are wrong

                                        Q191. In a practical transformer mutual induction between primary and secondary coils takes place. In such transformer what can be deduced about the power.

                                        • A. Power output = Power input
                                        • B. Power output > Power input
                                        • C. Power output ≥ Power input
                                        • D. Power output < Power input

                                        Explanation: The output power in a transformer is always less than the input power because of the different losses in a transformer. The losses may be Iron loss or core loss, hysteresis loss, eddy current loss, copper loss etc.

                                        Why the other options are wrong

                                          Q192. If slope of velocity time graph is not constant at different points then body is moving with:

                                          • A. Uniform velocity
                                          • B. changing acceleration
                                          • C. Average acceleration
                                          • D. Constant acceleration

                                          Explanation: Since the slope of the velocity time graph represents the acceleration of the body, hence a changing slope of the graph means that the acceleration is also changing.

                                          Why the other options are wrong
                                          • A. If a body is moving with uniform velocity (i.e., velocity remains constant with respect to time), the velocity-time graph is a straight line parallel to the time axis.
                                          • C. From a particle's velocity-time graph, its average velocity can be found by calculating the total area under the graph and then dividing it by the corresponding time-interval. For a particle with uniform acceleration, the velocity-time graph is a straight line.
                                          • D. If a particle is moving under constant acceleration, then the velocity –time graph is a straight line passing through the origin.

                                          Q193. Electric potential due to 2uC charge at distance of one meter is equal to:

                                          • A. 18 x 104 volt
                                          • B. 1.8 x 106 volt
                                          • C. 1.8 x 109 volt
                                          • D. 1.8 x 104 volt

                                          Explanation: V=KQ/r where K= coulomb's constant V=(9*109)*(2*10-6)/1 = 18000 volts = 1.8*104

                                          Why the other options are wrong
                                          • A. Incorrect as per formula
                                          • B. Incorrect as per formula
                                          • C. Incorrect as per formula

                                          Q194. Kirchhoff's first law is manifestation of:

                                          • A. Law of conservation of momentum
                                          • B. Law of conservation mass
                                          • C. Law of conservation of energy
                                          • D. Law of conservation of charge

                                          Explanation: Kirchhoff's first law states that the algebraic sum of current flowing into a junction is zero. This rule corresponds to conservation of charge which states that total charge in a closed system remains constant because current is the rate of flow of charge.

                                          Why the other options are wrong
                                          • A. This law states that the total linear momentum of an isolated system remains constant if no external forces act on it. Kirchhoff's first law is not related to the conservation of momentum; it primarily deals with the conservation of electric charge in a circuit.
                                          • B. This law states that the mass of a closed system remains constant over time. Kirchhoff's first law is not related to the conservation of mass; it specifically addresses the conservation of electric charge in electrical circuits.
                                          • C. This law states that energy cannot be created or destroyed, only converted from one form to another. Kirchhoff's first law is not directly related to the conservation of energy; instead, it deals with the conservation of charge.

                                          Q195. Light photons, each of energy 3.5 x 10-19J falls on the cathode of a photocell. The current through the cell is reduced to zero by taking the cathode to a potential +0.25 V relative to anode. The work function of the cathode is:

                                          • A. 3.35 x 10-19 J
                                          • B. 3.5 x 10-19 J
                                          • C. 3.25 x 10-19 J
                                          • D. 3.1 x 10-19 J

                                          Explanation: Explanation is given below.

                                          Why the other options are wrong
                                          • A. This option is incorrect as per the calculations
                                          • B. This option is incorrect as per the calculations
                                          • C. This option is incorrect as per the calculations

                                          Q196. A diffraction grating has 500 lines per mm, its grating element d is equal to:

                                          • A. 2 x 10-6 meter
                                          • B. 2 x 10-2 meter
                                          • C. 2 x 10-2 cm
                                          • D. 2 x 10-6 cm

                                          Explanation: The explanation is given below.Grating element = 1/N = 1/500 = 0.2 * 10-2 mm = 2 * 10-3 mm = 2 * 10-6 meter.

                                          Why the other options are wrong
                                          • B. This option is incorrect as per the formula.
                                          • C. This option is incorrect as per the formula.
                                          • D. This option is incorrect as per the formula.

                                          Q197. In the case of linear deformation, the ratio of tensile stress to tensile strain is called:

                                          • A. Energy stored in a stretched wire
                                          • B. Young’s double slit phenomenon
                                          • C. Bulk Modulus
                                          • D. Young’s Modulus

                                          Explanation: The Young's modulus (E) is a property of the material that tells us how easily it can stretch and deform and is defined as the ratio of tensile stress (σ) to tensile strain (ε). Where stress is the amount of force applied per unit area (σ = F/A) and strain is extension per unit length (ε = dl/l).

                                          Why the other options are wrong
                                          • A. Elastic potential energy is the potential energy stored by stretching or compressing an elastic object by an external force such as the stretching of a spring.
                                          • B. Young's original double-slit experiments were in fact the first to demonstrate the phenomenon of interference. When he shone light through two narrow slits and observed the pattern created on a distant screen, Young didn't find two bright regions corresponding to the slits, but instead saw bright and dark fringes.
                                          • C. The bulk modulus of a substance is a measure of how resistant to compression the substance is. It is defined as the ratio of the infinitesimal pressure increase to the resulting relative decrease of the volume.

                                          Q198. What is the name of the energy which is released when an atom is formed from its constituent particles?

                                          • A. Atomic Energy
                                          • B. Radioactive Energy
                                          • C. Nuclear Energy
                                          • D. Binding Energy

                                          Explanation: Binding energy, amount of energy required to separate a particle from a system of particles or to disperse all the particles of the system. Binding energy is especially applicable to subatomic particles in atomic nuclei, to electrons bound to nuclei in atoms, and to atoms and ions bound together in crystals.

                                          Why the other options are wrong
                                          • A. The energy that is released through a nuclear reaction or radioactive decay process.
                                          • B. Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles.
                                          • C. Nuclear energy is a form of energy released from the nucleus, the core of atoms, made up of protons and neutrons. This source of energy can be produced in two ways: fission – when nuclei of atoms split into several parts – or fusion – when nuclei fuse together.

                                          Q199. Calculate the half life of Bismuth-214 which has a decay constant of 4.3 x 10-4 s-1:

                                          • A. 2.9 x 10-3 s
                                          • B. 1.6 x 10^3 s
                                          • C. 3.9 x 103 s
                                          • D. 2.9 x 103 s

                                          Explanation: T1/2 = ln 2/𝞴 = 0.693/ 4.3 x 10-4 = 1.6 x 103 where 𝞴 = decay constant.

                                          Why the other options are wrong

                                            Q200. What is the main feature required by the optical fiber for the propagation of light in an optical fiber?

                                            • A. Optical glass should be cleaned
                                            • B. Light should be totally confined within the fiber
                                            • C. They are cheaper than copper wire
                                            • D. LED light must be used

                                            Explanation: Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. To ensure proper transmission light should be confined within the fiber.

                                            Why the other options are wrong
                                            • A. Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. To ensure proper transmission light should be confined within the fibre.
                                            • C. Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. To ensure proper transmission light should be confined within the fibre.
                                            • D. Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. To ensure proper transmission light should be confined within the fibre.

                                            Q201. Two long, parallel conductors which are free to move are arranged 1.0 cm apart. A steady current of 20 A flows in each of the conductors in the same direction. The conductors:

                                            • A. Remains stationary
                                            • B. Move towards each other
                                            • C. Move away from each other
                                            • D. Move at right angles to each other

                                            Explanation: When two parallel wires carry current in the same direction, they exert equal and opposite attractive forces on each other. This causes them to move towards one another.

                                            Why the other options are wrong

                                              Q202. A stone of mass 2.0 kg is dropped from a rest position 5.0 m above the ground. What is its velocity at a height of 3.0 m above the ground?

                                              • A. 12.5 m/s
                                              • B. 6.3m/s
                                              • C. 9.3 m/s
                                              • D. 16.0 m/s

                                              Explanation: Refer to following explanation

                                              Q203. In case of half wave rectification the resistance of diode during negative half of A.C is:

                                              • A. Very high
                                              • B. Very low
                                              • C. A few ohms
                                              • D. Negative

                                              Explanation: A half-wave rectifier converts an AC signal to DC by passing either the negative or positive half-cycle of the waveform and blocking the other. Half-wave rectifiers can be easily constructed using only one diode, but are less efficient than full-wave rectifiers. During negative half of half wave rectifier, the diode is reverse biased i.e the current of few ohms and hence very high resistance.

                                              Why the other options are wrong

                                                Q204. Newton first law of motion is also known as:

                                                • A. Law of inertia
                                                • B. Law of electromagnetism
                                                • C. Law of universal gravity
                                                • D. Law of conservation of momentum

                                                Explanation: The property of a body to remain at rest or to remain in motion with constant velocity is called inertia. Newton's first law is often called the law of inertia.

                                                Why the other options are wrong

                                                  Q205. When a potential difference is applied across the ends of a uniform wire of length l and radius r, a current I flows in the wire. If same potential difference is applied to the ends of another wire of the same material but of length 2l and radius 2r, the current in the wire is:

                                                  • A. I/4
                                                  • B. 2I
                                                  • C. I
                                                  • D. I/2

                                                  Explanation: R=ρl/AWhen radius is doubled : Area=2*pi*(2r) = 2*pi*4rHence the area has increased by 4 times.New resistance : Rx = ρ*2l/4A = ½ RV=IR where V remains same and R becomes halfI = V / ½RI become equal to 2I.

                                                  Why the other options are wrong
                                                  • A. This option is incorrect as per the formula and calculations
                                                  • C. This option is incorrect as per the formula and calculations
                                                  • D. This option is incorrect as per the formula and calculations

                                                  Q206. A shock wave is produced due to an earthquake which makes the buildings move in the direction of the shock wave. Which progressive wave would this be?

                                                  • A. Longitudinal wave
                                                  • B. Transverse wave
                                                  • C. Material wave
                                                  • D. Particle wave

                                                  Explanation: When an earthquake occurs, the shock-waves of released energy that shake the Earth and temporarily turn soft deposits, such as clay, into jelly (liquefaction) are called seismic waves, from the Greek 'seismos' meaning 'earthquake'.A 'P' body wave (primary body wave) (a type of seismic wave) is a compression (longitudinal) wave that induces the particles in the rock to vibrate back and forth in the same direction the wave moves.A longitudinal wave is a type of mechanical wave in which the oscillations or vibrations occur parallel to the direction of wave propagation. In a longitudinal wave, the particles of the medium through which the wave travels move back and forth in the direction of the wave. Examples of longitudinal waves include sound waves and seismic P-waves (primary waves). In the context of an earthquake, longitudinal waves can cause the ground to move back and forth parallel to the direction of wave propagation.

                                                  Why the other options are wrong
                                                  • B. A transverse wave is a type of mechanical wave in which the oscillations or vibrations occur perpendicular to the direction of wave propagation. In a transverse wave, the particles of the medium through which the wave travels move up and down or side to side perpendicular to the direction of the wave. Examples of transverse waves include electromagnetic waves (such as light waves) and seismic S-waves (secondary waves). Transverse waves typically do not cause the same kind of ground movement as longitudinal waves during an earthquake.
                                                  • C. The term "material wave" is not a standard term in physics. It may refer to waves that propagate through a material medium, which could include both longitudinal and transverse waves. Without a specific definition, it is unclear how this option relates to the phenomenon described.
                                                  • D. The term "particle wave" is also not a standard term in physics. It may refer to the wave-like behavior exhibited by particles in quantum mechanics, such as electrons in a double-slit experiment. However, in the context of mechanical waves like those produced by earthquakes, it is not directly relevant.

                                                  Q207. A neutron having mass equal to a proton (mp = 1.6 x 10-27 kg) is moving in a magnetic field of intensity 1.20 x 10-3 T with a speed of 2.0 x 107 ms-1 . What is the maximum force experienced by the neutron?

                                                  • A. 3.84 x 10-15 N
                                                  • B. 0
                                                  • C. 3.84 x 10-12 N
                                                  • D. 38.4 x 10-15 N

                                                  Explanation: Neutrons do not experience magnetic fields because it's a neutral particle, moving charged particles only experience the magnetic force

                                                  Why the other options are wrong

                                                    Q208. In SHM the kinetic energy of the body is maximum when:

                                                    • A. The body is at mean position
                                                    • B. The body is at extreme position from the mean
                                                    • C. The body is exactly half way down between mean and extreme position
                                                    • D. The body is somewhere between mean and extreme position

                                                    Explanation: In simple harmonic motion, there is a continuous interchange of kinetic energy and potential energy. At maximum displacement from the equilibrium point, potential energy is a maximum while kinetic energy is zero. At the equilibrium point (mean position) the potential energy is zero and the kinetic energy is a maximum.

                                                    Why the other options are wrong
                                                    • B. At extreme positions, the displacement of the body from the equilibrium position is maximum.However, while the potential energy is maximum at extreme positions, the kinetic energy is zero because the velocity of the body is momentarily zero.Hence, option B is incorrect.
                                                    • C. At this position, the body has both kinetic and potential energy, but neither is maximum.The kinetic energy is not maximum because the velocity of the body is not maximum at this position.Hence, option C is incorrect.
                                                    • D. Similar to option C, the body at positions between the mean and extreme positions has both kinetic and potential energy, but neither is maximum.The kinetic energy is not maximum because the velocity of the body is not maximum at these positions.Hence, option D is incorrect.

                                                    Q209. The different magnitudes of same physical quantities are measured by comparing them to:

                                                    • A. Available scale
                                                    • B. Standard size
                                                    • C. Each other
                                                    • D. Other physical quantities

                                                    Explanation: When the different magnitudes of certain physical quantities are measured then it should be measured according to a standard measure which is the same for everyone throughout the world. So that the distinguished quantities and the differences in the magnitude can be perfectly measured.

                                                    Why the other options are wrong

                                                      Q210. Force experienced per unit positive test charge at a point in an electric field is the definition of:

                                                      • A. Electric potential energy
                                                      • B. Electric field strength
                                                      • C. Electric potential
                                                      • D. Electric field

                                                      Explanation: The strength of an electric field E at any point may be defined as the electric, or Coulomb, force F exerted per unit positive electric charge q at that point, or simply E = F/q.

                                                      Why the other options are wrong
                                                      • A. Electric potential energy is the energy that is needed to move a charge against an electric field. FormulaUE=kq1q2/r2
                                                      • C. Electric potential, the amount of work needed to move a unit charge from a reference point to a specific point against an electric field. Typically, the reference point is Earth, although any point beyond the influence of the electric field charge can be used.
                                                      • D. An electric field (sometimes E-field) is the physical field that surrounds electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to the physical field for a system of charged particles

                                                      Q211. A metal rod of length 10.0 cm is moving at a speed of 0.5 ms-1 in a direction perpendicular to a 0.20 T magnetic field. Find the emf produced in the rod.

                                                      • A. 2.0 x 10-3 V
                                                      • B. 0.50 x 10-2 V
                                                      • C. 1.0 x 10-2 V
                                                      • D. 1.0 x 10-3 V

                                                      Explanation: Motional emf = Bℓv (B,ℓ, and v perpendicular) Emf = (0.20T) * (0.1m) * (0.5m/s) = 0.01 = 1 * 10-2 V

                                                      Why the other options are wrong

                                                        Q212. The dog sprang _ him.

                                                        • A. On
                                                        • B. Upon
                                                        • C. In
                                                        • D. Over

                                                        Explanation: The sentence "The dog sprang upon him" suggests that the dog leaped or jumped aggressively towards him. The preposition "upon" is used to indicate a sudden or forceful action in this context.

                                                        Why the other options are wrong
                                                        • A. "On," could also be used to indicate the dog's movement towards him, but "upon" is a more appropriate and commonly used preposition in this context.
                                                        • C. "In," does not accurately convey the action of the dog leaping towards him."In," does not accurately convey the action of the dog leaping towards him.
                                                        • D. "Over," suggests that the dog jumped over him rather than directly towards him.

                                                        Q213. I _ cricket every morning.

                                                        • A. Playing
                                                        • B. Plays
                                                        • C. Play
                                                        • D. Played

                                                        Explanation: When talking about a fact or a habitual activity, we use the present indefinite tense (also called the simple present tense). Hence, the correct option here would be 'play'.

                                                        Why the other options are wrong
                                                        • A. "playing" is the present participle and would be used in a continuous or progressive verb form, like "I am playing cricket every morning."
                                                        • B. "plays" is the third-person singular present tense, which doesn't match the subject "I".
                                                        • D. "played" is the simple past tense, which would indicate a completed action in the past, not a habitual one.

                                                        Q214. Demonstrate correct use of articles and prepositions Demonstrate correct use of subject-verb agreement Demonstrate correct use of writing conventions of spelling, capitalization and punctuation to clarify meaning:I advised her _ drink it.

                                                        • A. Don't
                                                        • B. Not to
                                                        • C. To not
                                                        • D. To don't

                                                        Explanation: A preposition must be placed before the adverb. Hence, the correct option is option B.

                                                        Why the other options are wrong
                                                        • A. A and D are incorrect as the sentence already has a main verb. In a single clause we use 1 main verb. If a sentence has multiple clauses, each clause has its own main verb.
                                                        • C. C is incorrect because the positioning of the adverb and preposition is wrong. Prepositions are written after adverbs.
                                                        • D. A and D are incorrect as the sentence already has a main verb. In a single clause we use 1 main verb. If a sentence has multiple clauses, each clause has its own main verb.

                                                        Q215. My parents _ near Lahore.

                                                        • A. Living
                                                        • B. Are living
                                                        • C. Lives
                                                        • D. Live

                                                        Explanation: Parents is a plural noun so the verb used should be singular.

                                                        Why the other options are wrong
                                                        • A. "Living near" is incorrect as it does not agree with the subject-verb agreement.
                                                        • B. "Are living" is also incorrect as it uses the present continuous tense, which is not suitable for describing a present state.
                                                        • C. "Lives" is incorrect as it is in the third-person singular form, which does not agree with the subject "my parents," which is in the plural form.

                                                        Q216. The two machines _ considerably. One has an electric motor, and the other one runs on oil.

                                                        • A. Different
                                                        • B. Differentiate
                                                        • C. Differ
                                                        • D. Difference

                                                        Explanation: the verb "differ" is the correct choice to complete the sentence and describe how the two machines have considerable differences between them.

                                                        Why the other options are wrong
                                                        • A. "Different" is an adjective, not a verb, so it doesn't fit the sentence structure.
                                                        • B. "Differentiate" means to recognize or ascertain the difference, which is not what the sentence is conveying.
                                                        • D. "Difference" is a noun, not a verb and so, it doesn't work in this context.

                                                        Q217. Which one has proper use of preposition?

                                                        • A. "If I am lying, the curse of Allah be on me and may I be drowned in some period. May I even be deprived from a decent burial!"
                                                        • B. "If I am lying. the curse of Allah be on me and may I be drowned in some period, May I even be deprived at a decent burial!"
                                                        • C. "If I am lying, the curse of Allah be on me and may I be drowned in some period. May I even deprived off a decent burial."
                                                        • D. "If I am lying, the curse of Allah be on me and may I be drowned in some period. May I even be deprived of a decent burial!"

                                                        Explanation: The preposition “of” is used to show possession or belonging. In this sentence, the speaker is saying that they may be deprived of something that they would normally have or deserve, which is a decent burial. The other options use incorrect prepositions or omit them altogether.

                                                        Why the other options are wrong
                                                        • A. This option includes the preposition "from" in the phrase "deprived from a decent burial." However, the more commonly used preposition in this context is "of," as mentioned in option D. So, option A does not have the proper use of preposition.
                                                        • B. This option includes the preposition "at" in the phrase "deprived at a decent burial." However, similar to option A, the more appropriate preposition to use in this context is "of," as mentioned in option D. Therefore, option B does not have the proper use of preposition.
                                                        • C. This option does not include a preposition in the phrase "deprived off a decent burial." The correct usage would be "deprived of a decent burial," as mentioned in option D. Therefore, option C does not have the proper use of preposition

                                                        Q218. Which of the following sentences is grammatically incorrect?

                                                        • A. Is this your jacket?
                                                        • B. Whose jacket is this?
                                                        • C. Is this jacket yours?
                                                        • D. Who's jacket is this?

                                                        Explanation: Another way to ask this question is to say “To whom does this jacket belong?”, so we’re talking about possession. “Who’s” is a contraction that’s short for “who is” or "who has", and it does not show ownership. The corrected form is noted above.

                                                        Why the other options are wrong
                                                        • A. This sentence is grammatically correct. It is a simple question asking if the jacket belongs to the person being addressed.
                                                        • B. This sentence is also grammatically correct. It is a question asking about the ownership of the jacket.
                                                        • C. This sentence is grammatically correct. It is another way of asking if the jacket belongs to the person being addressed, with a slight variation in word order.

                                                        Q219. Which of the following is grammatically correct?

                                                        • A. In the end, they found there money over they're by the ATM.
                                                        • B. In the end, they found they're money over their by the ATM.
                                                        • C. In the end, they found their money over there by the ATM.
                                                        • D. In the end, they found there money over their by the ATM.

                                                        Explanation: In this sentence, we have two homophones—their and there. In this first instance, we need to show possession, so the correct form is their. In the second instance, we need an adverb representing a place, so the correct form is there.

                                                        Why the other options are wrong
                                                        • A. This option is incorrect because it contains several grammatical errors. "There" should be "their" to indicate possession, and "they're" is the contraction of "they are" and doesn't fit in this context. Additionally, "over they're" is not a valid phrase.
                                                        • B. Similar to option A, this choice has errors. "They're" should be "their" to show possession. "Over their" is correct to indicate the location, but the placement of "by the ATM" is awkward.
                                                        • D. Option D contains two errors. "There" should be "their" to indicate possession. Additionally, "over their" is correct for indicating location, but the placement of "by the ATM" is incorrect.

                                                        Q220. Pick the correct option:

                                                        • A. No star is brighter than the moon.
                                                        • B. No star is more bright than the moon.
                                                        • C. No star is brighter then the moon
                                                        • D. No star is brighter than moon.

                                                        Explanation: More bright is wrong since, in the comparative verb form, bright becomes brighter. ”Than” should be used instead of then. Lastly, the article “the” should be used as the sentence is mentioning the moon, which is specific.

                                                        More Punjab / UHS Solved Papers