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Sindh Mdcat Mock Paper 3 — Solved Past Paper with Answers

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Q1. Choose the word most similar in meaning to the capitalized ones. UNAMBIGUOUS

  • A. Stagnant
  • B. Hidden
  • C. Clear
  • D. Muddy
  • E. Grubby

Explanation: The word 'unambiguous' means 'without any doubt' or 'clearly expressed.' The term 'clear' is synonymous with unambiguous as it indicates something easy to understand or interpret.

Why the other options are wrong
  • A. Stagnant (adjective) means lacking movement or flow, often leading to an unpleasant condition. This does not relate to clarity or lack of ambiguity.
  • B. Hidden (adjective) refers to something that is concealed or not visible. This is unrelated to clarity or lack of ambiguity.
  • D. Muddy (adjective) can mean confused or unclear, which is the opposite of unambiguous.
  • E. Grubby (adjective) refers to something dirty or grimy, which is unrelated to unambiguity or clarity.

Q2. Read the passage to answer the question:To inquire about the meaning or object of one's own existence or of creation generally has always seemed to me absurd from an objective point of view. And yet everybody has certain ideals that determine the direction of his endeavors and his judgments. In this sense, I have never looked upon ease and happiness as ends in themselves-such an ethical basis I call more proper for a herd of swine. The ideals which have lighted me on my way and time after time given me new courage to face life cheerfully, have been Truth, Goodness, and Beauty. Without the sense of fellowship with men of like mind, of preoccupation with the objective, the eternally unattainable in the field of art and scientific research, life would have seemed to me empty. The ordinary objects of human endeavor property, outward success, luxury-have always seemed to me contemptible.The author of the passage followed which of the following objectives?I.TruthII. GoodnessIII. BeautyIV. Saints

  • A. I only
  • B. II only
  • C. I and II only
  • D. I, II and III only
  • E. I, II, III and IV

Explanation: I, II, AND III are clearly mentioned as the objectives in line 6. This question can be answered by directly inferring from the passage.

Why the other options are wrong
  • A. Incorrect. The author does emphasize Truth as one of his guiding ideals, but he also mentions Goodness and Beauty. This option is too limited.
  • B. Incorrect. While the author values Goodness, he also mentions Truth and Beauty as essential ideals. This option excludes two significant elements.
  • C. Incorrect. Though Truth and Goodness are mentioned as guiding principles, the author explicitly includes Beauty as well. This option omits Beauty, making it incomplete.
  • E. Incorrect. The passage does not mention Saints as one of the author’s guiding principles. Including Saints makes this option inaccurate.

Q3. Identify the word or phrase that needs to be changed for the sentence to be correct:The office is so busy that two extra clerks have had to be taken on.

  • A. The
  • B. Busy
  • C. Extra
  • D. Have had
  • E. No error

Explanation: There is no error in the above sentence. The sentence is grammatically correct. "The office" is a proper subject, "is so busy" correctly describes its state, "two extra clerks" is correctly phrased, and "have had to be taken on" is properly structured in the present perfect passive voice.

Why the other options are wrong
  • A. Incorrect. "The office" is correctly used because it refers to a specific office, making "The" appropriate.
  • B. Incorrect. The adjective "busy" is correctly used to describe the office's state, so no change is needed.
  • C. Incorrect. "Extra" correctly modifies "clerks," indicating additional staff, so this word is correctly used.
  • D. Incorrect. "Have had to be taken on" is the correct present perfect passive construction, indicating that extra clerks were required and hired over time.

Q4. Identify the word or phrase that needs to be changed for the sentence to be correct.The guests broke a dozen glass at the party.

  • A. The guests
  • B. Broke
  • C. Glass
  • D. At
  • E. No Error

Explanation: The given sentence is an example of a simple sentence. A simple sentence contains a subject and a verb, and it may also have an object and modifiers. However, it contains only one independent clause.The word "glass" requires a change to the plural form "glasses." The word or phrase that needs to be changed for the sentence to be correct is "glass"" (should be changed to "glasses").

Why the other options are wrong
  • A. “The guests” is the subject of the given sentence. “The” is a definite article which is used to identify a specific noun (guests). The use of “the guests” in the given sentence makes sense grammatically and hence, does not need to be changed.
  • B. The verb “broke” is the past tense of “break”. A simple past verb is used to show an action that has already occurred and was completed at a particular time in the past. The use of the word “broke” in the given sentence makes sense grammatically and hence, does not need to be changed.
  • D. The word “at” is a preposition that is used to indicate a position in time or a place (the party). The use of the word “at” in the given sentence makes sense grammatically and hence, does not need to be changed.
  • E. This option suggests that there are no errors in the sentence and it is already correct.

Q5. Choose the correct spelling:

  • A. Exantuated
  • B. Axantuated
  • C. Accenchuated
  • D. Accentuated

Explanation: To "accentuate" means to “make more noticeable and prominent” and its correct spelling is given in Option D.

Why the other options are wrong
  • A. Exantuated is not a valid spelling of this word.
  • B. Axantuated is also not a valid spelling.
  • C. Accenchuated is misspelled, the correct spelling is "accentuated".

Q6. Complete the sentences by choosing the most appropriate option, from the given lettered choices below each. I was having a cup _ tea when he knocked on the door.

  • A. Off
  • B. At
  • C. An
  • D. Of

Explanation: The correct preposition to use is 'of'. In the phrase 'a cup of tea', 'of' indicates that the tea is contained within the cup, showing a relationship of content. The other options do not correctly express this relationship: 'off' suggests separation, 'at' implies location, and 'an' is not a preposition but an article.

Why the other options are wrong
  • A. 'Off' is used to indicate separation or removal, as in moving away from a surface or position. It does not fit the context of describing what the cup contains.
  • B. 'At' is commonly used to denote a specific location or time, such as 'at the park' or 'at 5 PM'. It is not suitable for indicating the contents of a cup.
  • C. 'An' is an indefinite article used before words that start with a vowel sound. It is not a preposition and does not convey a relationship between nouns.

Q7. Choose the correct option.

  • A. Samar bought an apple, an orange and an pear.
  • B. Samar bought an apple a orange and a pear.
  • C. Samar bought an apple, an orange and a pear.
  • D. Samar bought a apple, an orange and a pear.

Explanation: This option is correct. It correctly uses commas to separate the items in the list ("an apple", "an orange", and "a pear"), and the articles ("an" and "a") are used correctly.

Why the other options are wrong
  • A. This option is incorrect because "an pear" should be corrected to "a pear". The article "an" is used before words that start with a vowel sound, and "pear" starts with a consonant sound, so it should be "a pear".
  • B. This option is incorrect because it does not use commas to separate the items in the list ("an apple", "a orange", and "a pear"). Commas are needed to separate items in a series.
  • D. This option is incorrect because "a apple" should be corrected to "an apple". The article "a" is used before words that start with a consonant sound, and "apple" starts with a vowel sound, so it should be "an apple".

Q8. Complete the sentences by choosing the most appropriate option, from the given lettered choices (A to D) below each. The recent discoveries of medical science have_ life and health to millions of people.

  • A. Brought
  • B. Bring
  • C. Had bought
  • D. Bringing

Explanation: The question is talking about a thing that has already happened, so bringing and bring would not be correct options. Option C changes the word to “bought” which has a totally different meaning so is incorrect. So option A is correct.

Why the other options are wrong
  • B. "Bring" is the base form of the verb, but itdoesn't match the tense of the sentence. The sentence is in the present perfecttense, indicating actions that have occurred in the past with a connection tothe present.
  • C. "Had brought" is the past perfect tense, whichimplies an action that happened before another past action. However, there isno need to convey a sequence of past events in this sentence, so the pastperfect tense is not necessary.
  • D. "Bringing" is the present participle form of theverb "bring," which indicates an ongoing action. However, thesentence is talking about recent discoveries in the past that have already hadan impact on millions of people, so the present participle form is notsuitable.

Q9. The diagram shows the four types of human teeth. Which teeth are used for cutting rather than grinding food?

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

Explanation: Most adults have 32 permanent teeth, including eight incisors, four canines, eight premolars, and 12 molars. Incisors and canines are used to cut and chew. Premolars and molars are used for grinding the food.

Why the other options are wrong
  • B. Canines are sharp, pointy teeth used for tearing food, while premolars are located behind the canines and have broad surfaces for crushing and grinding food.
  • C. Premolars and molars are both teeth used for chewing and grinding food, but molars are larger, wider, and have more cusps (points) for grinding, while premolars are smaller and act as a transition between the canines and molars.
  • D. Incisors and molars are two different types of human teeth with distinct functions: incisors are sharp, front teeth used for cutting food, while molars are large, broad teeth in the back used for grinding food.

Q10. The inhibitor which closely resembles the substrate in its molecular structure and inhibits the enzyme activity by binding to the active site of the enzyme is called

  • A. Feedback inhibitor
  • B. Non-competitive inhibitor
  • C. Allosteric modulator
  • D. Competitive inhibitor

Explanation: In competitive inhibition, the inhibitor (I) closely resembles the real substrate (S) and is regarded as a substrate analog. The inhibitor competes with the substrate and binds at the active site of the enzyme but does not undergo any catalysis. As long as the competitive inhibitor holds the active site, the enzyme is not available for the substrate to bind. A competitive inhibitor diminishes the rate of catalysis by reducing the proportion of enzyme molecules bound to a substrate. At any given inhibitor concentration, competitive inhibition can be relieved by increasing the substrate concentration. So, the correct answer is 'Competitive inhibitor'.

Why the other options are wrong
  • A. Competitive inhibition occurs when molecules very similar to the substrate molecules bind to the active site and prevent binding of the actual substrate. Penicillin, for example, is a competitive inhibitor that blocks the active site of an enzyme that many bacteria use to construct their cell walls.
  • B. Competitive inhibition occurs when molecules very similar to the substrate molecules bind to the active site and prevent binding of the actual substrate. Penicillin, for example, is a competitive inhibitor that blocks the active site of an enzyme that many bacteria use to construct their cell walls.
  • C. Competitive inhibition occurs when molecules very similar to the substrate molecules bind to the active site and prevent binding of the actual substrate. Penicillin, for example, is a competitive inhibitor that blocks the active site of an enzyme that many bacteria use to construct their cell walls.

Q11. The gland known as the" gland of emergency" is the

  • A. Pituitary
  • B. Adrenal gland
  • C. Thyroid
  • D. Parathyroid
  • E. Pancreas

Explanation: The adrenal glands are often referred to as the "glands of emergency" because they play a crucial role in the body's stress response. These glands produce hormones such as adrenaline and cortisol, which prepare the body to respond to stressful situations by increasing heart rate, raising blood pressure, and mobilizing energy resources.

Why the other options are wrong
  • A. While the pituitary gland controls many important bodily functions by producing a variety of hormones, it is not typically referred to as the gland of emergency.
  • C. The thyroid gland plays a significant role in regulating metabolism, but it is not commonly known as the gland of emergency.
  • D. The parathyroid glands regulate calcium levels in the body but are not called the gland of emergency.
  • E. The pancreas produces insulin and other hormones involved in blood sugar regulation and digestion, but it is not known as the gland of emergency.

Q12. The autonomic nervous system controls all of the following activities except:

  • A. Digestion of food
  • B. Heart beat
  • C. Contraction of the pupil of the eye
  • D. Thought
  • E. Breathing rate

Explanation: Thought is a conscious action, so it is not controlled by the autonomic nervous system rather by the somatic nervous system. The autonomic nervous system regulates certain body processes, such as blood pressure and the rate of breathing. This system works automatically (autonomously), without a person's conscious effort.

Why the other options are wrong
  • A. Controlled by the parasympathetic division of the ANS.
  • B. Heartbeat → regulated by ANS (sympathetic and parasympathetic).
  • C. Contraction of the pupil of the eye → also controlled by the ANS.
  • E. Breathing rate is mainly controlled automatically by the autonomic nervous system.

Q13. Which of the following is the simplest form of pathogens causing diseases?

  • A. Viruses
  • B. Prions
  • C. Fungus
  • D. Amoeba

Explanation: Prions are the simplest disease-causing pathogens because they are merely misfolded proteins with with no nucleic acid (no DNA or RNA), making them the most minimal infectious agents compared to viruses, fungi, or protozoa like amoeba.

Why the other options are wrong
  • A. Viruses, while simple compared to many other life forms, still consist of genetic material (DNA or RNA) encapsulated in a protein coat. They require a host cell to reproduce and cannot independently cause disease, making them more complex than prions.
  • C. Fungi are complex organisms with defined cellular structures and reproductive mechanisms. They require specific environmental conditions to grow and are not the simplest pathogens, as they are multicellular or unicellular with extensive biological functions.
  • D. Amoebas are single-celled organisms that can cause diseases, but they are more complex than prions, as they possess cellular structures, organelles, and various pathogenic mechanisms. Thus, they do not represent the simplest form of pathogens.

Q14. The enzyme found in saliva responsible for the digestion of carbohydrates is:

  • A. Lysozyme
  • B. Amylase
  • C. Pepsin
  • D. Trypsinogen
  • E. Lipase

Explanation: The enzyme found in saliva responsible for the digestion of carbohydrates is amylase. Amylase breaks down complex carbohydrates, such as starches, into simpler sugars like maltose and glucose. Salivary amylase is produced by the salivary glands and is an important component of the initial stages of the digestive process, helping to initiate the breakdown of carbohydrates in the mouth before food travels to the stomach and further along the digestive tract.

Why the other options are wrong
  • A. Lysozyme is an enzyme that plays a role in the immune system by acting as an antimicrobial agent. Lysozyme is found in various bodily fluids, including saliva, tears, and mucus. It functions by breaking down the cell walls of certain bacteria, thereby helping to protect the body from infections.
  • C. Pepsin is an enzyme that plays a crucial role in the digestion of proteins. It is produced in the stomach, where it helps break down large protein molecules into smaller peptides. Pepsin works in an acidic environment, which is provided by the gastric acid in the stomach.
  • D. Trypsinogen is also an inactive precursor enzyme, similar to pepsinogen, but it is involved in the digestion of proteins in the small intestine. Trypsinogen is secreted by the pancreas into the small intestine, and it is activated to trypsin, an active enzyme, during the digestive process.
  • E. Lipase is an enzyme that plays a crucial role in the digestion of fats (lipids) in the digestive system. Lipases break down complex fats into simpler fatty acids and glycerol, which can then be absorbed by the body.

Q15. The process by which one molecule of Glucose splits up into molecules of Pyruvate is called:

  • A. Glycolysis
  • B. Oxidative Phospholyration
  • C. Electron Transport Chain
  • D. Kreb's Cycle
  • E. Calvin Cycle

Explanation: The process by which one molecule of glucose splits up into molecules of pyruvate is called glycolysis. Glycolysis is the first stage of cellular respiration, which occurs in the cytoplasm of the cell. During glycolysis, a molecule of glucose, a six-carbon sugar, is broken down into two molecules of pyruvate, each containing three carbon atoms.

Why the other options are wrong
  • B. The synthesis of ATP in the presence of oxygen is called oxidative phosphorylation.
  • C. In the Krebs cycle NADH and H+ are produced from NAD+. NADH and H+ transfer the hydrogen atoms to the respiratory chain also called the electron transport chain. Here, electrons are transported in a series of oxidation-reduction steps to react, ultimately, with oxygen.
  • D. A cyclic series of chemical reactions in which Acetyl CoA is oxidized to CO2 and ATP is generated is called the Krebs cycle. This cycle is also known as the citric acid cycle.
  • E. The cyclic series of reactions, catalyzed by enzymes, by which the carbon is fixed and reduced, resulting in the synthesis of sugar during the dark reactions of photosynthesis is called the Calvin cycle.

Q16. Movement of ions and large molecules with the help of protein molecules in and out of the cell is called _

  • A. Diffusion
  • B. Facilitated diffusion
  • C. Passive transport
  • D. Osmosis

Explanation: Diffusion is the passive movement of molecules down the concentration gradient whereas osmosis is the passive movement of water down the water potential gradient across a semi-permeable membrane. On the contrary, facilitated diffusion is the passive movement of molecules down the concentration gradient with the help of transport proteins (as these molecules/ions are incapable of moving through cell membranes directly).

Why the other options are wrong
  • A. Diffusion is the passive movement of substances down the concentration gradient ( generally small molecules) without the expenditure of energy.
  • C. Passive transport is a very generalized term used for all of diffusion, osmosis and facilitated diffusion.
  • D. Passive movement of water molecules down the water potential gradient across a semi-permeable membrane.

Q17. Match the parts of the human brain listed under Column I with the functions given under Column II. Choose the answer which gives the correct combination of alphabets of the two columns.

  • A. A=r, B=q, C=p, D=s
  • B. A=r, B s, C=q, D=t,
  • C. A=t, B=p, C=q, D=r
  • D. A=t, B=q, C=p, D=s

Explanation: Your cerebral hemisphere plays a key role in memory, intelligence, thinking, learning, reasoning, problem-solving, emotions, consciousness, and functions related to your senses. (so A=T, hence options A and B are incorrect). The thalamus is your body's information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation (so B=P, hence options A, B, and D are incorrect). The cerebellum controls voluntary movements such as walking, posture, balance, coordination, eye movements, and speech (C=Q). Neurons in the medulla also control arousal and sleep (D=R).

Why the other options are wrong
  • A. Your cerebral hemisphere plays a key role in memory, intelligence, thinking, learning, reasoning, problem-solving, emotions, consciousness, and functions related to your senses so A=T. The thalamus is your body's information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation, so B=P. This makes option A incorrect.
  • B. Your cerebral hemisphere plays a key role in memory, intelligence, thinking, learning, reasoning, problem-solving, emotions, consciousness, and functions related to your senses so A=T. The thalamus is your body's information relay station. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation, so B=P. This makes option B incorrect.
  • D. All information from your body's senses (except smell) must be processed through your thalamus before being sent to your brain's cerebral cortex for interpretation, so B=P. This makes option D incorrect.

Q18. The following statements are about enzymes: 1. They are globular proteins except ribo-enzyme.2. They can be inhibited3. They are formed in the smooth endoplasmic reticulum 4. There are only found attached to Plasma membranes in the cell Which statements are correct for all enzymes?

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

Explanation: Enzymes are a type of protein, and they have a three-dimensional, globular shape. This shape is crucial for their function, as it allows them to interact specifically with their substrates. Competitive inhibitors are molecules that closely resemble the substrate of an enzyme. They compete with the substrate for binding to the active site of the enzyme. When a competitive inhibitor binds to the active site, it prevents the substrate from binding and, as a result, inhibits the enzyme's normal catalytic activity.

Why the other options are wrong
  • A. The statement “all enzymes are proteins” is not correct.While most enzymes are indeed protein in nature, exceptions exist.RNA molecules with catalytic activity, called ribozymes, also function as enzymes.Example: the ribosome’s peptidyl-transferase activity is carried out by rRNA.Some synthetic DNA molecules (deoxyribozymes) also show catalytic roles.Hence, not every enzyme can be classified as a protein.Therefore, any option containing this statement, like A (1 and 4), is incorrect.
  • B. Competitive inhibitors are molecules that closely resemble the substrate of an enzyme. They compete with the substrate for binding to the active site of the enzyme. When a competitive inhibitor binds to the active site, it prevents the substrate from binding and, as a result, inhibits the enzyme's normal catalytic activity. Enzymes are not exclusively found attached to plasma membranes in cells. Enzymes are proteins that act as catalysts to facilitate and accelerate biochemical reactions, and they can be found in various cellular compartments, not just associated with the plasma membrane. The cellular location of enzymes depends on their specific functions and the processes they are involved in.
  • D. This statement is false. Enzymes are not exclusively found attached to plasma membranes in cells. Enzymes are proteins that act as catalysts to facilitate and accelerate biochemical reactions, and they can be found in various cellular compartments, not just associated with the plasma membrane. The cellular location of enzymes depends on their specific functions and the processes they are involved in.

Q19. About 55% of the volume of the human blood is?

  • A. Plasma
  • B. Blood proteins
  • C. Blood cells
  • D. Both B and C

Explanation: The correct answer is plasma, which makes up about 55% of the total blood volume. Plasma is a clear fluid consisting of 90% water and contains essential substances such as electrolytes, proteins, hormones, and nutrients. Blood proteins are an important part of plasma but do not constitute 55% of the blood volume on their own. Blood cells form the remaining 45% of the blood volume, encompassing red blood cells, white blood cells, and platelets, which are essential for various bodily functions but do not make up the majority of the blood volume.

Why the other options are wrong
  • B. Although blood proteins are a major component of plasma, they do not alone constitute 55% of the blood's volume. They perform essential functions such as clotting, immune responses, and transportation of various substances.
  • C. Blood cells, including red blood cells, white blood cells, and platelets, make up about 45% of the blood's volume. They are crucial for carrying oxygen, fighting infections, and clotting blood, but they do not account for 55% of the volume.
  • D. This option is incorrect because while blood proteins and blood cells are components of blood, together they do not constitute 55% of its volume. Plasma is the correct component that makes up approximately 55% of the blood volume.

Q20. Human cells maintain concentration gradients across their plasma membranes, such that there is a high sodium concentration outside the cell and a high potassium concentration inside the cell. Suppose that within the cell membrane are sodium leak channels or carrier proteins. These channels would allow sodium to:

  • A. Move out of the cell by simple diffusion
  • B. Move into the cell by simple diffusion
  • C. Move out of the cell by facilitated diffusion
  • D. Move into the cell by facilitated diffusion

Explanation: As the question mentions, there is a high concentration of sodium ions outside the cell, which means that through sodium leaky channels, the sodium ions should move inside the cell, not outside. The type of movement that occurs through channels or carrier proteins down the concentration gradient is called facilitated diffusion. That is why the answer is D.

Why the other options are wrong
  • A. Option A is wrong because neither sodium moves out of the cell nor is it transported via simple diffusion.
  • B. Option B is wrong because sodium does not transport via simple diffusion.
  • C. Option C is wrong because sodium moves inside the cell, not out of the cell.

Q21. Viruses resemble living things because they:

  • A. Circulate
  • B. Move
  • C. Reproduce
  • D. Are crystalline
  • E. Are able to respond to stimuli in the environment

Explanation: Only thing that makes a group of scientists want the virus to be classified as a living thing is its ability to reproduce. All other options are incorrect as non-living things can also exhibit these characteristics

Why the other options are wrong
  • A. Circulation is not the trait that makes viruses resemble with living things.
  • B. Movement is not the trait that makes viruses resemble with living things.
  • D. Viruses also have no metabolic processes (it is a set of chemical reactions which leads to growth, reproduction, and help respond to surroundings of any organism) like other living organisms. Thus they can be crystallized and understand the viral particles.
  • E. This is not the characteristic that makes viruses resemble with living things .

Q22. A/An _ is mostly a non-protein chemical compound that is required for the protein’s biological activity.

  • A. Active site
  • B. Substrate
  • C. Cofactor
  • D. Enzyme

Explanation: The correct answer is 'Cofactor'. A cofactor is a non-protein chemical compound required for the biological activity of some proteins, particularly enzymes. Cofactors can be metal ions or organic molecules and are essential for the catalytic activity of many enzymes.The other options are incorrect because:'Active site' refers to the region of the enzyme where the substrate binds, not a separate chemical compound.'Substrate' is the molecule upon which the enzyme acts, not a non-protein compound required for enzyme activity.'Enzyme' itself is a protein that facilitates biochemical reactions, whereas a cofactor is a non-protein component needed for some enzyme activities.

Why the other options are wrong
  • A. The active site is the part of an enzyme where the substrate binds and the reaction is catalyzed. It is not a separate chemical compound but a specific region of the enzyme.
  • B. The substrate is the specific reactant that an enzyme acts upon during a biochemical reaction. It is not a non-protein chemical compound required for the enzyme's activity.
  • D. Enzymes are proteins that catalyze biochemical reactions, often requiring cofactors to function properly. They are not non-protein compounds themselves.

Q23. A group of immune cells that mediate the cellular immune response by processing and presenting antigens for recognition of certain other cells or immune systems is called _.

  • A. Natural killer cells
  • B. Interferons
  • C. Antigen-presenting cells
  • D. Vaccines

Explanation: Antigen-presenting cells (APCs) like macrophages and dendritic cells display antigens to T-cells, activating immune response.

Why the other options are wrong
  • A. This option is incorrect. Natural killer cells are involved in the direct destruction of virus-infected and cancerous cells, but they do not process or present antigens.
  • B. This option is incorrect. Interferons are signaling proteins that help regulate the immune response rather than processing or presenting antigens.
  • D. This option is incorrect. Vaccines contain antigens or components that stimulate an immune response, but they are not cells that process or present antigens.

Q24. A psychological condition usually seen in girls and young women, with loss of appetite, is:

  • A. Obesity
  • B. Malnutrition
  • C. Anorexia Nervosa
  • D. Dyspepsia
  • E. Peptic ulcer

Explanation: Anorexia nervosa is a psychological disorder primarily affecting girls and young women, characterized by an intense fear of gaining weight and a distorted body image, leading to severe food intake restriction and loss of appetite. Unlike the other conditions listed, anorexia is specifically psychological and affects the demographic in question. Obesity is more about excessive weight gain, malnutrition is a broad term for nutrient deficiencies, dyspepsia is a digestive issue, and peptic ulcers are physical conditions of the digestive system.

Why the other options are wrong
  • A. Obesity is a medical condition characterized by excessive body weight and fat accumulation, often linked to overeating rather than a loss of appetite. It is not primarily psychological nor specific to girls and young women.
  • B. Malnutrition involves inadequate nutrition due to a lack of essential nutrients. While it can result in a loss of appetite, it is not a psychological condition specific to girls and young women, and it encompasses a range of nutritional deficiencies.
  • D. Dyspepsia, or indigestion, is a gastrointestinal condition characterized by discomfort in the upper abdomen. It can occasionally lead to a decreased appetite, but it is not primarily psychological or specific to girls and young women.
  • E. A peptic ulcer is a physical condition in the digestive system, caused by bacterial infection or prolonged NSAID use. While it can cause appetite loss, it is not a psychological condition nor specific to girls and young women.

Q25. The diagram represents the human respiratory system. While inhalation, which of the labelled muscles contract?

  • A. X only
  • B. X and Y only
  • C. X and Z only
  • D. Y and Z only
  • E. X, Y and Z

Explanation: During inhalation, the diaphragm (labelled as Z) and the external intercostal muscles (labelled as Y) contract to allow the lungs to expand and fill with air. The intercostal muscles labelled as X do not contract during this process; they relax. Hence, the correct answer is option D: Y and Z only. Options involving X are incorrect because X does not contract during inhalation.

Why the other options are wrong
  • A. X represents the intercostal muscles. During inhalation, the intercostal muscles that do not actively contract instead relax, allowing the ribcage to expand naturally. This relaxation works in coordination with the diaphragm and other muscles to increase thoracic volume and facilitate air entry into the lungs. Therefore, this option is incorrect.
  • B. While X represents intercostal muscles that relax during inhalation, Y represents the external intercostal muscles that do contract. However, this option is incomplete as it does not include Z, the diaphragm. Thus, this option is incorrect.
  • C. X represents intercostal muscles that relax during inhalation, not contract. Z represents the diaphragm that does contract during inhalation. This option is incorrect because it excludes Y, the external intercostal muscles that also contract.
  • E. X represents the intercostal muscles that relax during inhalation, so including it makes this option incorrect. Only Y and Z contract during inhalation.

Q26. Which is the incorrectly paired one?

  • A. Robert Hooke ... cell wall
  • B. Schlelden and Schwann ... cell theory
  • C. Robert Brown... nucleus
  • D. Watson and Crick ... DNA model
  • E. Virchow... Mosaic model of plasma membrane

Explanation: The Fluid Mosaic hypothesis was formulated by Singer and Nicolson in the early 1970s, not by Virchow. All others are correctly paired.

Why the other options are wrong
  • A. This is correct. Robert Hooke ... cell wall: Robert Hooke observed cork cells in 1665 and coined the term "cell." He also described the cell walls he saw in these structures.
  • B. This is correct. Schleiden and Schwann ... cell theory: Matthias Schleiden (botanist) and Theodor Schwann (zoologist) are credited with formulating the unified cell theory in the late 1830s, stating that all living things are composed of cells.
  • C. This is correct. Robert Brown ... nucleus: Robert Brown, a Scottish botanist, is recognized for discovering the cell nucleus in 1831. * Source: Robert Brown Discovered Nucleus
  • D. This is correct. Watson and Crick ... DNA model: James Watson and Francis Crick, along with contributions from Rosalind Franklin and Maurice Wilkins, proposed the double helix structure of DNA in 1953.

Q27. The disease caused by nutritional deficiency is:

  • A. Hepatitis
  • B. Cholera
  • C. Malaria
  • D. Beriberi
  • E. Alzheimer's

Explanation: Beriberi is caused by the deficiency of Vitamin-B1, which is a thiamine.All other diseases mentioned are caused by pathogens.

Why the other options are wrong
  • A. Hepatitis is an inflammation of the liver. It is usually caused by a viral infection, toxic agents, or drugs
  • B. Cholera is an acute, diarrheal illness caused by infection of the intestine with the toxigenic bacterium Vibrio cholerae.
  • C. Malaria is a serious and sometimes fatal disease caused by a parasite that commonly infects a certain type of mosquito that feeds on humans.
  • E. Alzeheimer is a non-pathogenic, inherited disorder.

Q28. Which diagram illustrates the process of active transport?

  • A. Option A
  • B. Option B
  • C. Option C
  • D. Option D

Explanation: Option D is correct because it illustrates active transport, where molecules move against their concentration gradient, requiring energy input, typically from ATP. The diagram likely shows molecules moving into a cell despite a higher concentration inside, indicative of active transport. Option A is incorrect as it shows passive movement, Option B is incorrect as it shows facilitated diffusion, and Option C shows osmosis, all of which do not require energy for the movement of molecules.

Why the other options are wrong
  • A. Option A shows passive transport, where molecules move from high to low concentration without energy use.
  • B. Option B depicts facilitated diffusion, which also moves molecules down their concentration gradient with the help of a protein carrier, but without energy.
  • C. Option C illustrates osmosis, the movement of water molecules through a selectively permeable membrane from low to high solute concentration, also not requiring energy.

Q29. Consider the following statements regarding blood pressure:1. It is the pressure exerted by the blood on the walls of any vessel.2. It decreases in the arteries as the distance from the heart increases.3. It is lower in the capillaries than in the arteries.4. It is usually lower in women than in men.Choose the correct statements:

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

Explanation: All statements are correct: blood pressure varies by vessel type, location, and gender, and is highest near the heart.

Why the other options are wrong
  • A. Blood pressure is literally defined as the force of blood pushing against the walls of blood vessels. As the blood moves further from the heart, there is a drop in blood pressure. This drop happens because of friction and resistance in the vessels. Arterial blood pressure (120/80 mmHg) is much higher than capillary pressure (20–40 mmHg).
  • B. As the blood moves further from the heart, there is a droo in blood pressure. This drop happens because of friction and resistance in the vessels. Arterial blood pressure (120/80 mmHg) is much higher than capillary pressure (20–40 mmHg). On average, women have slightly lower blood pressure than men of the same age. This is mainly due to difference in hormones.
  • C. Blood pressure is literally defined as the force of blood pushing against the walls of blood vessels. On average, women have slightly lower blood pressure than men of the same age. This is mainly due to difference in hormones.

Q30. It is the non-living component of the cell, it is secreted and maintained by the living portion of the cell and is found only in plants. What is this structure?

  • A. Golgi apparatus
  • B. Lysosome
  • C. Mitochondrion
  • D. Cell wall
  • E. Ribosomes

Explanation: The correct answer is the cell wall, which is a non-living component unique to plant cells among the options provided. It is secreted and maintained by the living parts of the cell, such as the plasma membrane and the Golgi apparatus. The cell wall provides structure, protection, and supports the plant cell against mechanical stress and osmotic pressure. It is primarily composed of cellulose in plants.Other options such as the Golgi apparatus, lysosomes, mitochondria, and ribosomes are all living organelles involved in various cell functions and are found in both plant and animal cells. They do not serve the structural role that the cell wall does.

Why the other options are wrong
  • A. The Golgi apparatus is a living organelle involved in modifying, sorting, and packaging proteins and lipids for secretion or use within the cell. It is found in both plant and animal cells.
  • B. Lysosomes are membrane-bound organelles that contain enzymes for digesting cellular waste and other substances. They are more commonly found in animal cells and are living components.
  • C. Mitochondria are energy-producing organelles found in both plant and animal cells. They are involved in cellular respiration and are living components.
  • E. Ribosomes are the site of protein synthesis in cells and are found in both plant and animal cells. They are living components and essential for translating genetic information into proteins.

Q31. Which of the following are found in both arteries and capillaries?

  • A. Connective tissues
  • B. Elastic fibres
  • C. Endothelial cells
  • D. Smooth muscle cells

Explanation: Endothelial cells line the inner surface of all blood vessels, including arteries and capillaries, allowing smooth blood flow and exchange of substances.

Why the other options are wrong
  • A. Connective tissues provide structural support to blood vessels, but they are prominently found in arteries and veins, not capillaries, due to the thinness of capillary walls.
  • B. Elastic fibers are abundant in arteries to help manage high pressure from blood flow, but they are not a significant component of capillaries.
  • D. Smooth muscle cells are primarily found in arteries and veins to regulate blood flow and pressure, but they are not a feature of capillaries.

Q32. A part of the digestive system that is not in contact with food is the:

  • A. Small intestine
  • B. Stomach
  • C. Liver
  • D. Large intestine
  • E. Oesophagus

Explanation: The liver aids in digestion by producing bile, a fluid that emulsifies fats in the small intestine, breaking them down into smaller, more manageable droplets for absorption. While the liver doesn't "digest" food directly, it creates the bile necessary for fat digestion, which is then stored in the gallbladder before being released into the small intestine when food is present. All others are those parts of the digestive tract that come in contact with the food.

Why the other options are wrong
  • A. The small intestine is the part of the digestive system that comes in contact with the food. Digestion in the small intestine is a process of chemical breakdown and nutrient absorption, where enzymes from the pancreas, liver, and the intestine itself break down food into smaller molecules like sugars, amino acids, and fatty acids.
  • B. The stomach is the part of the digestive system that comes in contact with the food. Digestion in the stomach involves mechanical and chemical processes where food is mixed with gastric juices, a mix of acid and enzymes, to break down food into a semi-liquid substance called chyme.
  • D. Large intestine is the part of digestive system that comes in contact with the food. The large intestine's primary roles are absorbing water and electrolytes, housing beneficial bacteria, and forming and storing feces for elimination.
  • E. The oesophagus is that part of the digestive system that comes in contact with the food. Digestion in the esophagus is primarily a process of mechanical movement, not chemical digestion. After food is swallowed, the esophagus uses muscular contractions called peristalsis.

Q33. The cell A, in the given figure is:

  • A. Gametophyte
  • B. Spermatogonium
  • C. Sperm
  • D. Spermatocyte
  • E. Spermatid

Explanation: Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. During spermatocytogenesis primitive cells called spermatogonia proliferate by mitosis. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II.

Why the other options are wrong
  • A. Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. During spermatocytogenesis primitive cells called spermatogonia proliferate by mitosis. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II.
  • C. Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. During spermatocytogenesis primitive cells called spermatogonia proliferate by mitosis. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II.
  • D. Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. During spermatocytogenesis primitive cells called spermatogonia proliferate by mitosis. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II.
  • E. Spermatogenesis is the process by which haploid spermatozoa develop from germ cells in the seminiferous tubules of the testis. During spermatocytogenesis primitive cells called spermatogonia proliferate by mitosis. The primary spermatocyte divides meiotically (Meiosis I) into two secondary spermatocytes; each secondary spermatocyte divides into two equal haploid spermatids by Meiosis II.

Q34. Formation of _ will be greater with the faster breakdown of glucose and glycogen to compensate for energy requirements in anaerobic respiration.

  • A. Enzymes
  • B. Hormones
  • C. Lactic acid
  • D. Fat

Explanation: In anaerobic respiration, when oxygen is scarce, glucose and glycogen are broken down to meet energy needs, resulting in lactic acid as a byproduct. This process does not produce enzymes or hormones as byproducts. Fat metabolism mainly occurs in the presence of oxygen and is not involved in this type of respiration.

Why the other options are wrong
  • A. Enzymes facilitate biochemical reactions, but they are not the end products of glucose or glycogen breakdown in anaerobic respiration.
  • B. Hormones regulate physiological processes but are not byproducts of anaerobic glucose or glycogen breakdown.
  • D. Fat is typically metabolized through aerobic pathways and is not a byproduct of anaerobic respiration.

Q35. What does 'a' in the following picture show?

  • A. Cellular pathway
  • B. Symplast pathway
  • C. Apoplast pathway
  • D. Water pathway

Explanation: Movement from cell to cell through plasmodesmata is a symplast pathway.Movement through the cell walls to the cell walls of other cells is called an apoplast pathway.

Why the other options are wrong
  • A. Cellular pathway: This is a broad term and doesn't specifically describe the pathway indicated by "a." While the symplast pathway is within cells, "cellular pathway" isn't precise enough.
  • C. Apoplast pathway: The apoplast is the space between cell walls and extracellular spaces. This is outside the cells, so "a" does not represent this.
  • D. Water pathway: This is too general. Both the apoplast and symplast pathways involve water movement, but "a" specifically refers to the symplast.Therefore, the correct answer is the Symplast pathway.

Q36. The function of a cell wall in prokaryotes is:

  • A. To give cells rigidity
  • B. To give specific shape
  • C. To protect from osmotic lysis
  • D. All of Above

Explanation: All prokaryotic cells have a stiff cell wall located underneath the capsule (if there is one). This structure maintains the 'cell's shape', protects the cell interior, and prevents the cell from bursting when it takes up water. Since the bacterial cell wall is 'thick and rigid', it will maintain the shape of the cell and also 'protect it from osmotic lysis' just like the cell wall of plants. Hence, the correct option is 'D'.

Why the other options are wrong
  • A. All prokaryotic cells have a stiff cell wall located underneath the capsule (if there is one). This structure maintains the 'cell's shape', protects the cell interior, and prevents the cell from bursting when it takes up water. Since the bacterial cell wall is 'thick and rigid', it will maintain the shape of the cell and also 'protect it from osmotic lysis' just like the cell wall of plants. Hence, the correct option is 'D'.
  • B. All prokaryotic cells have a stiff cell wall located underneath the capsule (if there is one). This structure maintains the 'cell's shape', protects the cell interior, and prevents the cell from bursting when it takes up water. Since the bacterial cell wall is 'thick and rigid', it will maintain the shape of the cell and also 'protect it from osmotic lysis' just like the cell wall of plants. Hence, the correct option is 'D'.
  • C. All prokaryotic cells have a stiff cell wall located underneath the capsule (if there is one). This structure maintains the 'cell's shape', protects the cell interior, and prevents the cell from bursting when it takes up water. Since the bacterial cell wall is 'thick and rigid', it will maintain the shape of the cell and also 'protect it from osmotic lysis' just like the cell wall of plants. Hence, the correct option is 'D'.

Q37. In 1959, Koshland proposed which of the following?

  • A. Unit membrane model
  • B. Fluid mosaic model
  • C. Reflective index model
  • D. Induced fit model

Explanation: In 1959, Daniel E. Koshland, an American biochemist, proposed the "induced fit" model of enzyme-substrate interaction. This model is an extension of the earlier "lock and key" model proposed by Emil Fischer. The induced fit model suggests that the active site of an enzyme is flexible and can undergo conformational changes upon binding to a substrate. In other words, the enzyme is not a rigid structure with a pre-formed active site (as implied by the lock and key model), but rather, the binding of the substrate induces changes in the enzyme's structure to achieve optimal interaction.

Why the other options are wrong
  • A. The concept of the "unit membrane" was initially proposed by J.D. Robertson in the 1950s. It refers to the basic structural organization of biological membranes, such as cell membranes and certain organelle membranes.
  • B. The fluid mosaic model was proposed by S.J. Singer and G.L. Nicolson in 1972 and is a widely accepted model describing the structure and dynamics of biological membranes.
  • C. The refractive index of a material is a measure of how much light is bent, or refracted, as it passes through that material. The refractive index is calculated as the ratio of the speed of light in a vacuum to the speed of light in the material.

Q38. The diagram shows some organs of the digestive system. Where is amylase present?

  • A. 1,4 and 5
  • B. 1,2 and 3
  • C. 2,6 and 4
  • D. 3,5 and 4

Explanation: Amylase is mostly present in the mouth, in pancreatic juice, and ileum; hence, option A is correct. Amylase is not present in the liver, no enzyme is present in the large intestine and only pepsin (protease) is present in the stomach. That is why, all other options B, C and D are wrong.

Why the other options are wrong
  • B. Amylase is not present in the stomach and liver. So, it is the wrong option.
  • C. Amylase is not present in the stomach and large intestine. So, it also will be the wrong option.
  • D. Amylase is not present in liver. So, it is the wrong option.

Q39. Which of the following statement(s) is/are correct regarding a nucleus? I.Stores wastes and other SubstancesII.Contains genetic materialIII.Helps in cellular transport systemIV.Control centre of the cell

  • A. I only
  • B. I&II
  • C. II & III
  • D. II & IV
  • E. III & IV

Explanation: Nucleus is the control centre of the cell and stores the genetic material of the cell,so we say that statements II and IV are correct, making option D correct. Nucleus does not store wastes and other substances plus it also does not help in cellular transport system, that eliminate option A,B,C and E.

Why the other options are wrong
  • A. Nucleus doesn't store wastes and any other kind of substances. Nucleus is the governor house of cell. It controls the life and activities of cells.
  • B. Nucleus stores genetic material but doesn't store any kind of wastes . So , statement II makes option B incorrect.
  • C. Nucleus doesn't help in cellular transport system. So , this option is incorrect.
  • E. Nucleus is the control center of cell but does not help in cellular respiration. Thus , statement III makes option E incorrect.

Q40. Which of the following nutrients is incorrectly paired with its function in a plant?

  • A. Potassium - Formation of cell wall.
  • B. Magnesium - Constituent of chlorophyll.
  • C. Nitrogen - Constituent of protein.
  • D. Phosphorus - Component of nucleic acid.

Explanation: The plant cell wall is made of Cellulose.Potassium creates the cell membrane potential which allows the cell to generate an action potential.Magnesium in plants is located in the enzymes, in the heart of the chlorophyll molecule.A phosphate backbone is the portion of the DNA double helix that provides structural support to the molecule.

Why the other options are wrong
  • B. Magnesium - Constituent of chlorophyll: Magnesium is the central atom in the chlorophyll molecule, which is essential for photosynthesis.
  • C. Nitrogen - Constituent of protein: Nitrogen is a key component of amino acids, which are the building blocks of proteins. Proteins are vital for plant growth and development.
  • D. Phosphorus - Component of nucleic acid: Phosphorus is a component of nucleic acids like DNA and RNA, which carry the genetic information of the plant. Phosphorus is also important in ATP, the energy currency of cells.Therefore, the only incorrect

Q41. The disease, which is caused by a defect in a single gene or pair of genes is referred to as:

  • A. Unifactorial
  • B. Multifactorial
  • C. Down syndrome
  • D. Turner syndrome

Explanation: The disease, which is caused by a defect in a single gene or pair of genes is referred to as a unifactorial gene.

Why the other options are wrong
  • B. Multifactorial diseases involve multiple genes and often environmental factors. These are complex traits, and examples include heart disease and diabetes.
  • C. Down syndrome is a chromosomal disorder caused by an extra copy of chromosome 21, not by a defect in a single gene.
  • D. Turner syndrome is a chromosomal disorder caused by the complete or partial absence of one X chromosome, not by a defect in a single gene.

Q42. Which organ(s) in the male reproductive system produce gametes?

  • A. Vas deferens
  • B. Malpighian tubule system
  • C. Seminiferous tubules
  • D. Ejaculatory duct
  • E. Testicular Duct System

Explanation: In mammals production of testes occurs in the seminiferous tubules of the male testes.The male genitals include the testes, the ductus deferens, the seminal vesicles, the ejaculatory ducts, and the penis, together with the following accessory structures: the prostate and the bulbourethral glands.The testes are two glandular organs, which secrete the semen; they are suspended in the scrotum by the spermatic cords.Testosterone is the principal hormone in a group of hormones called androgens. In men, testosterone is produced by the testes, in women, testosterone is primarily secreted by the ovaries.It is derived from cholesterol (like all the sex hormones) and its immediate precursor is DHEA.

Why the other options are wrong
  • A. Vas deferens transports sperm from the epididymis to the ejaculatory ducts
  • B. The Malpighian tubule system is a type of excretory and osmoregulatory system found in some insects, myriapods , arachnids and tardigrades .
  • D. The ejaculatory ducts are paired structures in male anatomy. Each ejaculatory duct is formed by the union of the vas deferens with the duct of the seminal vesicle
  • E. The testicular reproductive system includes the testes, the epididymis, the penis, and the ducts and glands that produce and carry sperms

Q43. Menstruation, the shedding of the lining of the uterus (endometrium), is accompanied by:

  • A. Shivering
  • B. Fever
  • C. Bleeding
  • D. Vomiting
  • E. Headache

Explanation: Menstruation is the shedding of the endometrium, which results in bleeding from the uterus. It is a normal physiological process that occurs in females of reproductive age. It is not usually accompanied by shivering, fever, vomiting or headache.

Why the other options are wrong
  • A. Shivering refers to involuntary muscle contractions that generate heat to increase body temperature. It is not directly related to menstruation or the shedding of the uterine lining.
  • B. Fever is an elevated body temperature often caused by an immune response to an infection. While some women may experience a slight increase in body temperature during menstruation, it is not typically considered a common or defining symptom of menstruation.
  • D. Vomiting, or the forceful expulsion of stomach contents through the mouth, is not a typical symptom of menstruation. While some women may experience nausea or digestive discomfort during their menstrual cycle, vomiting is not directly associated with menstruation.
  • E. Headaches or migraines can occur before or during menstruation for some women. Changes in hormone levels, particularly a drop in estrogen, can trigger headaches in some individuals. However, it is important to note that not all women experience headaches during menstruation, and there can be various causes for headaches unrelated to menstruation.

Q44. In addition to smaller hind limb muscle mass, the mutant "mini Muscle” gene exhibits lower heart rates during physical activity, and larger kidneys and livers in mice. This is a very good example of _.

  • A. Epistasis
  • B. Multiple alleles
  • C. Codominance
  • D. Pleiotropy

Explanation: Pleiotropy is a genetic situation where one gene impacts multiple, seemingly unrelated phenotypic traits. The example of the 'mini Muscle' gene impacting muscle mass, heart rate, and organ sizes in mice illustrates this principle. The other options are incorrect because they describe different genetic phenomena: Epistasis involves gene interactions, Multiple alleles involve more than two gene variants, and Codominance involves equal expression of two alleles rather than a single gene affecting multiple traits.

Why the other options are wrong
  • A. This option is incorrect. Epistasis involves interactions between different genes where one gene masks or modifies the expression of another gene, rather than a single gene affecting multiple traits.
  • B. This option is incorrect. Multiple alleles refer to the existence of more than two allelic forms of a gene within a population, not the influence of one gene on multiple traits.
  • C. This option is incorrect. Codominance occurs when two alleles are expressed equally in a phenotype, resulting in a distinct expression of both alleles, rather than a single gene affecting multiple traits.

Q45. What does the following picture show?

  • A. Motor Neuron
  • B. Sensory Neuron
  • C. Interneuron
  • D. Nerve

Explanation: The diagram illustrates a sensory neuron. The defining feature is the cell body, which connects to the dendrites via dendron processes. This structure is specific to sensory neurons and is not found in motor neurons, where the cell body directly attaches to dendrites. Interneurons are characterized by processes that are similar in size to the cell body, which is not evident here. Lastly, the term 'nerve' refers to a collection of neurons, whereas the image shows only one neuron.

Why the other options are wrong
  • A. This is incorrect. Motor neurons have their cell body attached directly to the dendrites without the presence of dendron processes, which are characteristic of sensory neurons.
  • C. This is incorrect. Interneurons typically have shorter processes that are comparable in size to the cell body, unlike what is shown in the image.
  • D. This is incorrect. A nerve consists of many neurons bundled together, whereas the image shows a single neuron.

Q46. The synapse formed at the sites where the terminal branches of the axon of a motor neuron conduct to a target muscle cell is called:

  • A. Sensory end plate
  • B. Synapse end plate
  • C. Motor end plate
  • D. Postsynaptic membrane

Explanation: The motor end plate is the specialized area at the neuromuscular junction where the axon terminal of a motor neuron forms a synapse with a muscle fiber. It is responsible for transmitting neural signals to muscle cells, resulting in muscle contraction. The term sensory end plate is associated with sensory neurons, not motor neurons. Synapse end plate is not a recognized term in neuroscience. The postsynaptic membrane refers generically to the membrane receiving neurotransmitters at any synapse, not specifically at neuromuscular junctions.

Why the other options are wrong
  • A. This term refers to the receptor region on sensory neurons, not motor neurons, which is involved in receiving sensory stimuli rather than muscle innervation.
  • B. This is not a standard term in neuroscience; it does not refer to a recognized anatomical or functional structure.
  • D. This is the membrane on the receiving side of a synapse, not specific to neuromuscular junctions, and is common in neuron-to-neuron synapses.

Q47. Which of the following is a uni-nucleated cell?

  • A. Skeletal muscle
  • B. Cardiac muscle
  • C. Smooth muscle
  • D. Both B and C

Explanation: Smooth muscles are uni-nucleated and non-striated. It is composed of small spindle-shaped cells with a single, central nucleus. They have unbranched cells that are controlled by the autonomic nervous system. The function of smooth muscle is to contract like any muscle tissue.

Why the other options are wrong
  • A. Skeletal muscle cells are multinucleated, meaning they have multiple nuclei within a single cell. This characteristic is due to the fusion of multiple precursor cells called myoblasts during muscle development. The multinucleation is important for the functioning and contractile abilities of skeletal muscles.
  • B. Cardiac muscle cells, also known as cardiomyocytes, are typically uninucleated or binucleated. Unlike skeletal muscle cells, which are multinucleated, each cardiac muscle cell typically contains one or two nucleus. This characteristic is consistent with the structure and function of the heart, where cardiac muscle cells work together in a coordinated manner to facilitate the pumping of blood.
  • D. This option is incorrect

Q48. Why are skeletal muscles called striated muscles?

  • A. Appear darker than smooth muscles by naked eye
  • B. Alternating dark and light bands appear on their surface when visualized by naked eye
  • C. Alternating dark and light bands appear on their surface when visualized via a microscope
  • D. All of these

Explanation: The striated appearance of skeletal muscle tissue is a result of repeating bands of the proteins actin and myosin that are present along the length of myofibrils. Dark A bands and light I bands repeat along myofibrils, and the alignment of myofibrils in the cell causes the entire cell to appear striated or banded.

Why the other options are wrong
  • A. This option is incorrect, as skeletal muscles are called striated muscles, as alternating dark and light bands appear on their surface when visualized via a microscope.
  • B. This option is incorrect, as skeletal muscles are called striated muscles, as alternating dark and light bands appear on their surface when visualized via a microscope.
  • D. This option is incorrect.

Q49. The smallest contractile unit of muscle contraction, called a sarcomere, is the area between two?

  • A. H zone
  • B. M line
  • C. Z line
  • D. Z zone

Explanation: The correct answer is the Z line. The sarcomere is the basic contractile unit of muscle fibers and is defined by the area between two Z lines. These lines serve as anchor points for actin filaments and help maintain the structure during contraction. The H zone and M line are internal components of the sarcomere that do not define its boundaries. The term 'Z zone' is not used in muscle anatomy; thus, it is not a correct option.

Why the other options are wrong
  • A. The H zone is the lighter region in the middle of the A-band, where there are only myosin filaments. It shortens during muscle contraction as actin filaments slide toward the M line.
  • B. The M line is found in the center of the sarcomere and holds the thick myosin filaments together, but does not define the boundaries of a sarcomere.
  • D. 'Z zone' is not a recognized term in muscle anatomy, making it an incorrect choice for this question.

Q50. In the sliding filament theory of muscle contraction, which option correctly describes function of ATP?

  • A. ATP does all of these things during muscle contraction
  • B. It allows the myosin head to detach from the actin filament
  • C. It moves tropomyosin off of actin binding sites
  • D. both A and B

Explanation: What is the role of ATP in sliding filament theory?Energy from ATP is required for the myosin head to release from the actin filament—otherwise the myosin heads would remain in the same place, and the muscle would not contract. Even though the filaments are moving, the filaments themselves never actually get shorter or longer.Sliding filament theory:• During muscle contraction, thin filaments show sliding inward towards the H-zone.• Sarcomere shortens, without changing the length of thin and thick myofilaments.• The cross bridge of the thick myofilaments connects with the portions of actin of the thin myofilaments. These cross bridge move on the surface of the thin myofilaments resulting to sliding of thin and thick myofilaments over each other.• A muscle fibre maintains a resting potential under resting conditions just like a nerve fibre as soon as nerve impulses reach the terminal end of the axon, small sacs called synaptic vesicles to fuse with the axon membrane and release a chemical transmitter, acetylcholine. • Acetylcholine diffuses across the synaptic cleft and binds to the receptor sites of the motor and plate.• As soon as depolarization of the motor end plate reaches and plate reaches a certain level, it creates an action potential. After this, an enzyme cholinesterase present along with the receptor sites for acetylcholine breaks down acetylcholine into acetate and choline. • The area of contact between a nerve and muscle fibre is called motor end plate or muscular junction.• Calcium plays a key regulatory role in muscle contraction. These ions bind to troponin causing a change in its shape and position. This, in turn, alters and the position of tropomyosin. This shift exposes the active sites on the F-actin and myosin cross-bridges are then able to bind these active sites. • The head of each myosin molecule contains an enzyme myosin ATPase. In the presence of myosin ATPase, calcium ions and Magnesium ions, ATP breaks down into ADP and inorganic phosphate and some amount of energy.• Energy from ATP causes energized myosin, cross bridges to bind to actin. The energized cross bridge move causing thin myofilaments to slide along the thick myofilaments.

Why the other options are wrong
  • A. ATP does all of these things during muscle contraction": While ATP is crucial for the overall process, it doesn't directly handle all the steps described in the other options.
  • C. It moves tropomyosin off of actin binding sites": This is primarily the role of calcium ions (Ca2+). When calcium levels are high in the sarcoplasm (muscle cell cytoplasm), it binds to troponin, causing a conformational change in the tropomyosin-troponin complex, which exposes the actin binding sites for myosin. ATP is not directly involved in this process.
  • D. both A and B": Since B is incorrect (as explained above), this combination is also incorrect.

Q51. Cross bridges are found on:

  • A. Actin
  • B. Myosin
  • C. Troponin
  • D. Tropomyosin

Explanation: Cross-bridges are formed by the myosin heads, which extend from the thick filaments (myosin) and interact with the thin filaments (actin) during muscle contraction. These cross-bridges are crucial for the sliding filament mechanism, where the myosin heads attach to binding sites on actin, undergo a power stroke, and pull the actin filaments closer together.

Why the other options are wrong
  • A. Actin is a protein that, along with myosin, is a crucial component of muscle fibers. It plays a central role in muscle contraction by forming filaments and participating in the sliding filament theory, where actin and myosin filaments slide past each other, causing muscle contraction. Actin is also involved in various cellular processes, including cell movement and maintenance of cell shape.
  • C. Troponin is a protein involved in muscle contraction, particularly in regulating the interaction between actin and myosin filaments. It is commonly used as a biomarker in blood tests to diagnose heart muscle damage, such as during a heart attack.
  • D. Tropomyosin is a protein that plays a role in muscle contraction by regulating the interaction between actin and myosin filaments. It covers myosin-binding sites on actin and controls the muscle contraction process.

Q52. A man who has type AB blood cannot father a child with type _ blood, because he would pass on either the _ or the B allele to all of his offspring.

  • A. A,O
  • B. O,A
  • C. B, O
  • D. B, A

Explanation: The father can pass on either the A or B allele to each of his offspring. Even if the mother has blood type O, the child cannot have blood type O because of the A or B allele received from the father. A and B alleles are dominant over O. For blood type O (the recessive phenotype) to occur, there should be two copies of the O allele, one from each parent. This is impossible in the given situation.

Why the other options are wrong
  • A. a) A, O – IncorrectThe statement says the man cannot father a child with type A or type O.But this is wrong because he can have a child with type A if the other parent contributes an "A" or "O" allele (e.g., if the mother is type A or O).However, he cannot have a child with type O, so the "O" part is correct, but "A" makes this option incorrect
  • C. c) B, O – IncorrectThe statement suggests he cannot have a child with type B or O.But he can have a child with type B if the mother contributes a B or O allele.Again, he cannot have a child with type O, but including B in the option makes it incorrect.
  • D. d) B, A – IncorrectThis statement says he cannot have a child with type B or type A, but this is wrong because he can have children with both A and B blood types, depending on the other parent's alleles.Since both A and B are possible, this option is incorrect.

Q53. A cross between a black cat and a tan cat produces a tabby pattern (black and tan fur together). What percent of kittens would have tan fur if a tabby cat is crossed with a black cat?

  • A. 100%
  • B. 50%
  • C. 25%
  • D. 0%

Explanation: The correct answer is 0%. The black cat is homozygous for the black fur gene (BB) and does not carry an allele for tan fur. The tabby cat, being a hybrid, has one black fur allele (B) and one tan fur allele (T). When crossed with a black cat, the potential offspring genotypes are BB (black) and BT (tabby), with no possibility of a TT (tan) genotype. Thus, none of the kittens will have tan fur. The other options are incorrect because they suggest the presence of a tan allele in the black parent, which is not possible given the genetic information provided.

Why the other options are wrong
  • A. If all offspring were tan, it would mean both parents carry only the tan gene, which is not the case here. The cross involves a tabby cat (BT) and a black cat (BB), which cannot produce tan-only offspring.
  • B. For 50% of the offspring to be tan, the tabby cat would need to pass the tan gene (T) to half of its offspring, but the black cat (BB) has no tan gene to contribute.
  • C. For 25% of the offspring to be tan, there must be a recessive tan gene present in both parents, but the black cat (BB) does not carry a tan allele.

Q54. Which of the following is not an important function of bone?

  • A. Regulation of ion concentration
  • B. Muscular contraction
  • C. Organ and nerve protection
  • D. Regulation of pH through hydration

Explanation: Bones help buffer blood pH by absorbing or releasing alkaline salts, but hydration is not the mechanism involved in this regulation. This phrase is misleading and not considered a valid function of bone.

Why the other options are wrong
  • A. This option is incorrect, as it is an important function of bone.
  • B. Indirectly true. Bones store calcium, which is essential for muscle contraction.
  • C. This option is incorrect, as it is an important function of bone.

Q55. Haemophilia is a sex-linked _ trait.

  • A. Dominant
  • B. Co-dominant
  • C. Pleiotropic
  • D. Recessive

Explanation: Haemophilia is a sex-linked recessive disorder. The abnormal gene responsible for haemophilia is carried on the X chromosome. Recessiveness is proved by the fact that when a woman has this gene on one X and a normal gene on the other X (heterozygous for hemophilia), she does not show haemophilia in phenotype.

Why the other options are wrong
  • A. a) Dominant – Incorrect because haemophilia is not a dominant trait; affected males only need one faulty X chromosome, but females need two.
  • B. b) Co-dominant – Incorrect because there is no equal expression of both normal and mutant alleles.
  • C. c) Pleiotropic – Incorrect because pleiotropy refers to one gene affecting multiple traits, while haemophilia specifically affects blood clotting.

Q56. The "d" and "D" alleles are used for lighter and darker skin colour in humans, respectively. By keeping in view the inheritance pattern of skin colour in human beings(controlled by 3 genes), choose which combination shows medium skin colour from the following picture:

  • A. Column A
  • B. Column C
  • C. Column D
  • D. Column E

Explanation: The correct answer is Column C because it presents a balanced number of dominant (D) and recessive (d) alleles across all three genes, which results in a medium skin color. In contrast, Column A is incorrect as it shows homozygous recessive alleles (ddd) for all genes, leading to the lightest possible skin color. Column D is incorrect because it fails to show a balance between dominant and recessive alleles, skewing towards either lighter or darker skin. Column E is incorrect as it does not reflect the polygenic nature of skin color inheritance, which involves multiple genes working together, not just a single gene or row.

Why the other options are wrong
  • A. This option is incorrect because it displays homozygous recessive genotypes (ddd) for all three genes, leading to the lightest possible skin color.
  • C. This option is incorrect because it showcases a predominance of either dominant or recessive alleles, which does not result in a medium skin color.
  • D. This option is incorrect as it does not adequately represent the polygenic nature of skin color determination, which requires a combination of multiple genes rather than a focus on a single row.

Q57. Monosynaptic reflex arc consists of:

  • A. One sensory neuron only
  • B. One motor neuron only
  • C. Two neurons, One sensory neuron, and one motor neuron
  • D. None of these

Explanation: The correct option is C. When a reflex arc consists of only two neurons, one sensory neuron and one motor neuron, it is defined as monosynaptic. It allows for direct communication between sensory and motor neurons, resulting in muscle stimulation. A common example of a monosynaptic reflex is the knee-jerk reflex.

Why the other options are wrong
  • A. "One sensory neuron only" is incorrect because the pathway also includes a motor neuron to carry out the response.
  • B. "One motor neuron only" is incorrect because a reflex arc requires sensory input to initiate the reflex.
  • D. "None of these" is incorrect because a monosynaptic reflex arc does exist and involves exactly two neurons.

Q58. The type of plastids found in roots of plants _ .

  • A. Chloroplasts
  • B. Chromoplasts
  • C. Leucoplasts
  • D. All of them

Explanation: The correct answer is Leucoplasts. These are non-pigmented plastids found in non-photosynthetic tissues such as roots, where their primary role is to store substances like starch, oils, and proteins. Chloroplasts are found in green tissues and are involved in photosynthesis, making them unsuitable for roots. Chromoplasts are responsible for the colors in flowers and fruits due to their pigments. Therefore, neither chloroplasts nor chromoplasts are typically found in roots. The option 'All of them' is incorrect because not all plastids are present in roots; only leucoplasts are typically found there.

Why the other options are wrong
  • A. Chloroplasts are primarily involved in photosynthesis and are found in green parts of plants such as leaves.
  • B. Chromoplasts are responsible for pigment synthesis and storage, contributing to the vibrant colors of fruits and flowers.
  • D. Not all plastids are found in roots; only leucoplasts are typically located there, as they function in storage, not photosynthesis or pigmentation.

Q59. Outbreeding increases which of the following?

  • A. Homozygosity
  • B. Heterozygosity
  • C. Gene linkage
  • D. Gene pool

Explanation: The correct answer is option 'B', 'heterozygosity'. Outbreeding increases heterozygosity by encouraging the mixing of different alleles, which enhances genetic variation and can improve the fitness of a population. This increased variation allows populations to better adapt to environmental changes and reduce the likelihood of expressing deleterious recessive alleles. Option 'A', 'homozygosity', is incorrect because outbreeding typically reduces homozygosity. Option 'C', 'gene linkage', is unaffected by outbreeding as it is related to the proximity of genes on a chromosome. Option 'D', 'gene pool', refers to the collection of genes within a population, and while outbreeding can influence it, the direct effect of outbreeding is an increase in heterozygosity.

Why the other options are wrong
  • A. Homozygosity refers to having identical alleles at a gene locus. Outbreeding typically reduces homozygosity as it increases genetic diversity.
  • C. Gene linkage refers to the tendency of genes located close to each other on a chromosome to be inherited together. Outbreeding does not directly affect gene linkage.
  • D. The gene pool is the total genetic diversity found within a population or a species. While outbreeding can contribute to the gene pool's diversity, it specifically increases heterozygosity.

Q60. Homology means?

  • A. Similarity in characteristics due to shared ancestry
  • B. Similarity in function due to acquired characteristics
  • C. Study of similar structures regardless of origin
  • D. Structures with different functions but similar appearances

Explanation: Homology is a fundamental concept in evolutionary biology that refers to similarities in characteristics due to shared ancestry. For instance, the forelimbs of humans, bats, and whales are homologous because they evolved from a common ancestor, despite having different current functions.Option A is correct because it accurately describes homology as stemming from shared ancestry. Option B is incorrect; it confuses acquired traits with inherited ones, which are central to homology. Option C is incorrect because it disregards the crucial element of common ancestry. Option D is incorrect because it describes analogy, where similar functions evolve independently, not from a shared ancestor.

Why the other options are wrong
  • B. This is incorrect. Similarity in function as a result of acquired characteristics does not imply shared ancestry. Homology involves inherited traits from a common ancestor, not traits acquired during an organism's lifetime.
  • C. This is incorrect. The key aspect of homology is the common evolutionary origin of structures. Simply studying similar structures without considering their ancestry does not define homology.
  • D. This is incorrect. This describes analogous structures, which evolve independently in different species to perform similar functions, not due to a shared ancestry. Homology focuses on the common origin, not function.

Q61. Biological molecules which catalyze a biochemical reaction and remain unchanged after completion of reaction are called?

  • A. Cofactor
  • B. Coenzymes
  • C. Activator
  • D. Enzymes

Explanation: Option D is correct as "enzymes" catalyse reactions and don't take part in the response; therefore, they do not change.

Why the other options are wrong
  • A. A cofactor is a non-protein chemical compound that is required for the biological activity of certain enzymes. It may be a metal ion such as Mg²⁺, Zn²⁺, or Fe²⁺, and its main role is to assist the enzyme in catalysis by stabilizing the enzyme-substrate complex or participating in the reaction. However, cofactors alone cannot catalyze biochemical reactions; they only support enzyme activity. Therefore, cofactors are not the biological molecules that independently catalyze reactions and remain unchanged afterward..
  • B. Coenzymes are organic cofactors, often derived from vitamins such as NAD⁺, FAD, or coenzyme A. They bind to the enzyme temporarily or permanently and help in transferring specific groups (like electrons or acyl groups) during reactions. Although coenzymes assist enzymes, they are not themselves catalysts. In many cases, coenzymes undergo chemical changes during the reaction and later return to their original state in subsequent cycles. Hence, they do not fit the definition of biological molecules that catalyze and remain unchanged after the reaction.
  • C. An activator is a substance that increases enzyme activity, often by helping the enzyme achieve its proper shape or by enhancing substrate binding. For example, certain metal ions like Mg²⁺ or Ca²⁺ act as activators. However, activators do not directly catalyze biochemical reactions; they only boost the catalytic efficiency of enzymes. Therefore, they cannot be called biological catalysts, as they do not perform the reaction themselves and are not essential reaction agents.

Q62. Out of 31 pairs of spinal nerves, how many pairs of thoracic nerves are there?

  • A. 8
  • B. 10
  • C. 12
  • D. 15

Explanation: In total, there are 31 pairs of spinal nerves grouped regionally by spinal region. More specifically, there are eight cervical nerve pairs (C1-C8), twelve thoracic nerve pairs (T1-T12), five lumbar nerve pairs (L1-L5), 5 sacral (S1-S5), and a single coccygeal nerve pair.

Why the other options are wrong
  • A. Cervical nerves have 8 pairs, not thoracic nerves.
  • B. There are 12 pairs of thoracic nerves, not 10.
  • D. There are 12 pairs of thoracic nerves. 15 pairs are not present in any region.

Q63. What affect do enzymes have on the activation energy of a reaction?

  • A. Increases
  • B. Decreases
  • C. No affect
  • D. Increases or decreases depending upon individual enzyme

Explanation: b) Decreases:Option (b) "Decreases" is the correct answer. Enzymes significantly decrease the activation energy of a reaction. By providing an alternative reaction pathway with a lower energy barrier, enzymes allow reactant molecules to achieve the transition state more easily and, as a result, the reaction rate is enhanced.

Why the other options are wrong
  • A. "Increases" is not the correct answer. Enzymes do not increase the activation energy of a reaction. In fact, the primary function of enzymes is to lower the activation energy, making it easier for the reaction to proceed.
  • C. "No affect" is not the correct answer. Enzymes do have an effect on the activation energy. They specifically lower the activation energy, as mentioned above.
  • D. "Increases or decreases depending upon individual enzyme" is not the correct answer. All enzymes function to decrease the activation energy of their respective reactions. The general role of enzymes is to facilitate reactions by lowering the energy barrier.

Q64. Virus attachment requires energy?

  • A. Yes
  • B. No
  • C. Provided by cell usually
  • D. Provided by virus machinery

Explanation: The attachment of a virus to a host cell does not require energy. The process of virus attachment is typically mediated by specific viral surface proteins, which bind to specific receptor molecules on the surface of the host cell. This binding process is typically a highly specific and spontaneous interaction, and it is often the first step in the process of viral infection. Therefore, the attachment of a virus to a host cell does not generally require energy.

Why the other options are wrong
  • A. This option is incorrect. Yes: Virus attachment to a host cell typically does not require energy expenditure by the virus. It's largely a passive process driven by the specific binding of viral attachment proteins to receptors on the host cell surface. Think of it like a lock and key mechanism.
  • C. This option is incorrect. Provided by cell usually: While the host cell provides the receptors that the virus binds to, the energy for the initial attachment event itself doesn't usually come directly from the cell in an active sense.
  • D. This option is also incorrect. Provided by virus machinery: Viruses are acellular and lack their own metabolic machinery to generate energy for attachment. The binding is based on the inherent chemical affinities between the viral and host cell surface molecules.

Q65. 'Biomolecules' such as starch, cellulose and glycogen yield which of the following upon hydrolysis?

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

Explanation: Option C is correct since the three most abundant polysaccharides, starch, glycogen, and cellulose ( referred to as homopolymers) yield only one type of monosaccharide i.e. 'glucose' after complete hydrolysis.

Why the other options are wrong
  • A. a) Maltose: Maltose is a disaccharide composed of two glucose molecules linked together. It is formed by the hydrolysis of starch or glycogen. So, it does not yield maltose upon hydrolysis.
  • B. b) Sucrose: Sucrose is also a disaccharide composed of one glucose molecule and one fructose molecule linked together. It is commonly found in table sugar. The hydrolysis of biomolecules like starch, cellulose, and glycogen does not yield sucrose.
  • D. d) Galactose: Galactose is another monosaccharide, similar to glucose. It is not the primary product obtained from the hydrolysis of starch, cellulose, and glycogen. Instead, glucose is the main product.

Q66. Haemoglobin in men increases the oxygen carrying capacity of the blood to about _.

  • A. 50 times
  • B. 65 times
  • C. 70 times
  • D. 75 times

Explanation: Option D is correct since 'Haemoglobin' is the most important protein present in many animals including man as it increases the oxygen-carrying capacity of blood to about 75 times.Myoglobin has naturally more afiinity for oxygen and is found in muscles.

Why the other options are wrong
  • A. This option suggests that haemoglobin in men increases the oxygen-carrying capacity of the blood to about 50 times. However, this statement is not correct. Haemoglobin in men does not increase the oxygen-carrying capacity of the blood to such a high extent.
  • B. This option states that haemoglobin in men increases the oxygen-carrying capacity of the blood to about 65 times. While haemoglobin does significantly increase the oxygen-carrying capacity of the blood, it does not increase it to this extent. This option is not accurate.
  • C. This option suggests that haemoglobin in men increases the oxygen-carrying capacity of the blood to about 70 times. This statement is also not correct. Haemoglobin increases the oxygen-carrying capacity of the blood, but the actual increase is not this high.

Q67. Which one is not a monosaccharide?

  • A. Galactose
  • B. Fructose
  • C. Mannose
  • D. Lactose

Explanation: Lactose is not a monosaccharide but a disaccharide,as shown below:

Why the other options are wrong
  • A. Galactose is a monosaccharide, specifically a hexose, which contains six carbon atoms.
  • B. Fructose is also a monosaccharide, known for being a simple sugar found in many plants.
  • C. Mannose is another example of a monosaccharide, often involved in carbohydrate metabolism.

Q68. The first human hormone that was produced by recombinant DNA technology was:

  • A. Insulin
  • B. Estrogen
  • C. Thyroxin
  • D. Progesterone

Explanation: The recombinant DNA technological processes have made a great impact in the area of health care by mass production of safe and more effective therapeutic drugs. In 1983, Eli Lily, an American company, first prepared two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of Escherichia coli to produce insulin chains. Chains A and B were produced separately, extracted, and combined by creating disulfide bonds to form human insulin (humulin).

Why the other options are wrong
  • B. Estrogen is naturally produced in the human body, and it has not been the focus of recombinant DNA technology for initial production.
  • C. Thyroxin is a hormone naturally produced by the thyroid gland. It was not the first hormone synthesized using recombinant DNA technology.
  • D. Progesterone is produced by the corpus luteum naturally, and it was not the first hormone to be synthesized using recombinant DNA technology.

Q69. Pierrie Curie and Marie Curie isolated which radioactive element?

  • A. Lithium
  • B. Radium
  • C. Boron
  • D. Uranium

Explanation: The correct answer is Radium. Marie and Pierre Curie successfully isolated radium from pitchblende in 1902, contributing greatly to the understanding of radioactivity. Lithium and boron are non-radioactive elements, and uranium, while radioactive, was discovered earlier by Martin Klaproth, not by the Curies.

Why the other options are wrong
  • A. Lithium is a chemical element discovered by Johan August Arfwedson in 1817 and is not radioactive.
  • C. Boron is a non-radioactive element discovered by Joseph Louis Gay-Lussac and Louis Jacques Thénard in 1808.
  • D. Uranium was discovered by Martin Heinrich Klaproth in 1789. Although it is radioactive, it was not isolated by the Curies.

Q70. Removal of proximal convoluted tubule from the nephron will result in:

  • A. No change in quality and quantity of urine
  • B. No urine formation
  • C. More diluted urine
  • D. More concentrated urine

Explanation: This is correct because the PCT is responsible for reabsorbing a large amount of water and solutes like glucose, amino acids, and sodium. If it is removed, less water and solutes will be reabsorbed, leading to increased water content in the urine, making it more diluted.

Why the other options are wrong
  • A. This is incorrect because the proximal convoluted tubule (PCT) is essential for the reabsorption of water and solutes. Its removal would result in significant changes in urine composition and volume.
  • B. This is incorrect because urine formation is a complex process involving multiple parts of the nephron. Even without the PCT, other nephron sections continue to contribute to urine production.
  • D. This is incorrect because the PCT is responsible for significant reabsorption of water. Its absence would result in more water being retained in the urine, thus making it more diluted rather than concentrated.

Q71. Which of the following molecules have zero Dipole Moment?

  • A. CCl4
  • B. CO2
  • C. Cl2
  • D. C6H6
  • E. All of the above

Explanation: All the molecules listed have a zero dipole moment due to their symmetrical structures:CCl4: Although it has polar C-Cl bonds, the tetrahedral symmetry results in a net dipole moment of zero.CO2: The linear shape with two opposing C=O bonds results in the cancellation of dipole moments.Cl2: As it consists of identical atoms, no dipole moment arises.C6H6 (Benzene): The planar symmetrical structure leads to the cancellation of dipole moments of C-H bonds.Therefore, the correct answer is 'All of the above'.

Why the other options are wrong
  • A. The CCl4 molecule has zero dipole moment. Despite the polar C-Cl bonds, the symmetrical tetrahedral shape causes the dipoles to cancel each other out.
  • B. CO2 is a linear molecule. The bond dipole moments in the opposing C=O bonds cancel each other, resulting in a zero dipole moment.
  • C. Cl2 consists of two identical atoms, resulting in no net dipole moment due to the absence of a charge difference.
  • D. Benzene (C6H6) has a symmetrical planar structure. The dipole moments of the C-H bonds cancel out, leading to a zero net dipole moment.

Q72. Plants absorb it in the form of soluble phosphates. It is present abundantly in the growing and storage organs of plants. What is it?

  • A. H2O
  • B. CO2
  • C. K
  • D. P
  • E. N

Explanation: Plants absorb phosphorus in the form of soluble phosphates, and it is stored abundantly in growing and storage organs like seeds and fruits, making it the correct answer.

Why the other options are wrong
  • A. H2O, or water, is crucial for plants but is not related to phosphates. The question focuses on phosphorus, not water.
  • B. CO2, or carbon dioxide, is used in photosynthesis but is unrelated to phosphorus absorption.
  • C. K, or potassium, is another essential nutrient for plants, but it does not aid in phosphate absorption or storage.
  • E. N, or nitrogen, is vital for chlorophyll and amino acids, but it does not relate directly to phosphate absorption or storage.

Q73. The Taq polymerase enzyme is obtained from:

  • A. Bacillus subtilis
  • B. Pseudomonas putida
  • C. Thermus aquaticus
  • D. Thiobacillus ferroxidase.

Explanation: Taq polymerase, generally used in PCR, is isolated from thermophilic bacterium Thermus aquaticus.

Why the other options are wrong
  • A. Bacillus subtilis is a bacterium used in various biotechnological applications, but it is not the source of Taq polymerase.
  • B. Pseudomonas putida is a different bacterium and is not the source of Taq polymerase used in PCR.
  • D. Thiobacillus ferroxidase is not associated with Taq polymerase production or PCR. It's a different bacterium with its characteristics.

Q74. What will be the energy of an X-ray quantum of wave length 1.0 x 10-10 m?

  • A. 0.6 x 10^-15 J
  • B. 1.98 x 10^-15 J
  • C. 3.7 x 10^-15 J
  • D. 4.7 x 10^-15 J
  • E. 7.7 x 10^-15 J

Explanation: So, the energy of x rays is 1.98 x 10 -15 J. Hence, this is the required solution.

Why the other options are wrong
  • A. This option is incorrect because it does not correctly calculate the energy using the given wavelength.
  • C. This option is incorrect because it does not correctly calculate the energy using the given wavelength.
  • D. This option is incorrect because it does not correctly calculate the energy using the given wavelength.
  • E. This option is incorrect because it does not correctly calculate the energy using the given wavelength.

Q75. If 92 U 235, decays by emitting two α one β and two γ -rays the new daughter element is = _.

  • A. 88 Y 227
  • B. 89 Y 227
  • C. 90 Y 227
  • D. 89 Y 231

Explanation: When 92U235 undergoes two alpha decays, it loses 4 protons and 8 neutrons, reducing the atomic number to 88 and the mass number to 227. The emission of a beta particle converts a neutron to a proton, increasing the atomic number by 1 to 89 without affecting the mass number. Gamma rays have no effect on the atomic or mass numbers as they are energy emissions without mass or charge. Thus, the resulting daughter element is 89Y227.Option A is incorrect as it miscalculates the decay process. Option C assumes no beta decay effect. Option D incorrectly calculates the mass number post-decay.

Why the other options are wrong
  • A. This option assumes incorrect changes to both atomic and mass numbers during decay. Two alpha decays and one beta decay do not lead to this configuration.
  • C. This option suggests only alpha decays occurred, without considering the effect of the beta decay which increases the atomic number by 1.
  • D. This option does not account for the mass number change after two alpha decays, which should decrease the mass number by 8.

Q76. Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because:

  • A. There is a negative pressure in the lungs
  • B. There is a negative intarpleural pressure pulling at the lung walls
  • C. There is a positive intrapleural pressure
  • D. Pressure in the lungs is higher than the atmospheric pressure.

Explanation: Negative intrapleural pressure helps keep the lungs expanded even after forceful expiration.

Why the other options are wrong
  • A. There is a negative pressure in the lungs": This statement is not entirely accurate. Lungs don't naturally have a negative pressure, and they can't be filled with air if there is a consistent negative pressure. Lungs maintain a degree of positive pressure to keep them expanded.
  • C. There is a positive intrapleural pressure": This statement is not accurate. A positive intrapleural pressure would not be conducive to maintaining lung expansion; it's the negative intrapleural pressure that plays a critical role in preventing lung collapse.
  • D. Pressure in the lungs is higher than the atmospheric pressure": This is not correct. The pressure in the lungs, during exhalation, is generally close to atmospheric pressure, but it's the intrapleural pressure that is negative, not the pressure in the lungs themselves.

Q77. What forms the basis of DNA fingerprinting?

  • A. The relative proportions of purines and pyrimidines in DNA
  • B. The relative difference in the DNA occurrence in blood, skin, and saliva
  • C. The relative amount of DNA in the ridges and grooves of the fingerprints
  • D. Satellite DNA occurring as highly repeated, short DNA segments

Explanation: DNA fingerprinting is a technique of determining nucleotide sequences of certain areas of DNA which are unique to each individual. The difference of about 0.1% or 3 × 106 base pairs (out of 3 × 10 9 bp) provides individuality to each human being. The human genome possesses numerous small noncoding but inheritable sequences of bases that are repeated many times. These sequences occur near telomere, centromeres, Y chromosome, and heterochromatic area. The area with the same sequence of bases repeated several times is called repetitive DNA. It is separated as a satellite from the bulk DNA during density gradient centrifugation and hence called satellite DNA where repetition of the bases is in tandem. Satellite DNAs show polymorphism (the occurrence of mutations in a population at high frequency), which is the basis of genetic mapping of human genome as well as DNA fingerprinting. While mutations in genes produce alleles with different expressions, mutations in noncoding repetitive DNA have no immediate impact. These mutations which have piled up with time form the basis of polymorphism.

Why the other options are wrong
  • A. DNA fingerprinting is not based on the relative proportions of purines (adenine and guanine) and pyrimidines (cytosine and thymine) in DNA. It focuses on specific DNA sequences.
  • B. While DNA can be obtained from blood, skin, and saliva for DNA fingerprinting, this option does not directly address the basis of DNA fingerprinting, which involves analyzing specific DNA sequences, not the source of the DNA.
  • C. This option is not related to the basis of DNA fingerprinting. It seems to refer to the physical impressions of fingerprints rather than the genetic analysis of DNA.

Q78. The torque will be greater if:

  • A. Both magnitude of force and moment arm are smaller
  • B. Both magnitude of force and moment arm are greater
  • C. Only magnitude of force is greater
  • D. Only moment arm is greater
  • E. None of the above

Explanation: The formula for torque is T=Fr. Hence Torque will be greater if the magnitude of the force and moment arm are greater.

Why the other options are wrong
  • A. If both the magnitude of the force and the moment arm are smaller, the torque will decrease, not increase.
  • C. While increasing the magnitude of the force will increase torque, it will not be maximized unless the moment arm is also increased.
  • D. Increasing only the moment arm will increase torque, but not as much as increasing both the force and the moment arm together.
  • E. This option is incorrect because increasing either the force or the moment arm, or both, can increase the torque.

Q79. The translocation of organic solutes in sieve-tube members is supported by:

  • A. Cytoplasmic streaming
  • B. Root pressure and transpiration pull
  • C. P-proteins
  • D. Mass flow involving a carrier and ATP

Explanation: According to the mass flow hypothesis, the transport of organic solutes takes place from source to sink, this transport also depends on metabolic energy. According to the cytoplasmic streaming hypothesis (which was given by de Vries, in 1885) the transport of organic solutes takes place by a combination of diffusion and cytoplasmic streaming. Cytoplasmic streaming carries organic solutes from one end to the other end of the sieve tube. P-proteins have a role as a defense against phloem-feeding insects and the sealing of damaged sieve tubes. So, the correct answer is 'Mass flow involving a carrier and ATP'. So correct option is C.

Why the other options are wrong
  • A. Cytoplasmic streaming is the movement of cytoplasm within a cell but is not the primary mechanism behind the long-distance transport of organic solutes in the phloem.
  • B. Root pressure and transpiration pull are involved in the movement of water (xylem transport) but are not directly responsible for the transport of organic solutes in the phloem.
  • C. P-proteins, also known as phloem proteins, are involved in sealing off damaged sieve-tube members to prevent the loss of sap. While they play a role in phloem physiology, they are not the primary drivers of organic solute translocation.

Q80. Guttation is the result of:

  • A. Diffusion
  • B. Transpiration
  • C. Osmosis
  • D. Root pressure
  • E. Becomes half

Explanation: Various ions from the soil are actively transported into the vascular tissues of roots, water follows its potential gradient and increase the pressure inside the xylem. This positive pressure is called root pressure. Effect of root pressure is observable at night and early morning when evaporation is low and excess water collects in the form of droplets near the tip of leaves of many herbaceous plants. Such water loss in its liquid phase is known as guttation. It is the movement of molecules from high to low concentration down the gradient. Transpiration is the loss of water in vapour form from leaves. Osmosis is the movement of water molecules from higher to lower concentration through semi permeable membrane. So correct option is D.

Why the other options are wrong
  • A. It is the movement of molecules from high to low concentration down the gradient.
  • B. Transpiration is the loss of water in vapors form from leaves.
  • C. Osmosis is the movement of water molecules from higher to lower concentration through semi-permeable membrane.
  • E. This option is not correct because if the diameter of the Earth doubles, the distance from the center of the Earth to the surface would also double. According to the law of universal gravitation, the gravitational force between two objects is inversely proportional to the square of the distance between them. Therefore, if the distance between the object and the center of the Earth doubles, the gravitational force experienced by the object would be reduced to one-fourth of its original value, not halved.

Q81. The first clinical gene therapy was given for treating:

  • A. Diabetes mellitus
  • B. Chicken pox
  • C. Rheumatoid arthritis
  • D. Adenosine deaminase deficiency.

Explanation: Gene therapy is a collection of methods that allows the correction of a gene defect that has been diagnosed in a child/embryo. Here genes are inserted into a person’s cells and tissues to treat a disease. Correction of a genetic defect involves the delivery of a normal gene into the individual or embryo to take over the function of and compensate for the non­functional gene. The first clinical gene therapy was given in 1990 to a 4- year old girl with adenosine deaminase (ADA) deficiency. This enzyme is very important for the immune system to function. SCID is caused due to defect in the gene for the enzyme adenosine deaminase. In some children, ADA deficiency can be cured by bone marrow transplantation. Here, the isolated gene from bone marrow cells producing ADA is introduced into cells at early embryonic stages; it can be a permanent cure.

Why the other options are wrong
  • A. Gene therapy for diabetes mellitus had been a subject of research, but there was no established gene therapy treatment widely available for diabetes. The treatment of diabetes primarily relied on other approaches such as insulin therapy, oral medications, and lifestyle management
  • B. Gene therapy for chickenpox is not a standard or established treatment. Chickenpox is caused by the varicella-zoster virus, and traditionally, the primary means of managing chickenpox and related conditions like shingles has been through vaccination and antiviral medications. Gene therapy has not been a common or established approach for managing chickenpox or related viral infections.
  • C. RA is a complex autoimmune disease, and its treatment primarily involves medications, physical therapy, and other non-genetic therapeutic approaches. Gene therapy research was exploring the potential for targeted interventions in RA, but no specific gene therapy had been approved or widely used for the treatment of RA.

Q82. The basic functional unit of human kidney is

  • A. Nephridia
  • B. Loop of Henle
  • C. Pyramid
  • D. Nephron

Explanation: A nephron is a unit of structure and function in a kidney. A kidney contains about a million nephrons, each approximately 3 cm long. A nephron is a long tubule differentiated into four regions having different anatomical features and physiological role : Bowman’s capsule, proximal convoluted tubule (PCT), loop of Henle, and distal convoluted tubule (DCT). The latter opens into one of the collecting ducts. Nephridia are the excretory organs of annelids.

Why the other options are wrong
  • A. Nephridia is the excretory organ of many invertebrates, consisting of a tubule with one end opening into the body cavity and the other opening into a pore at the body surface.
  • B. The loop of Henle is a part of the Nephron in the kidneys, which helps to reabsorb water and salt from the kidney tubules.
  • C. The main renal pyramid function is to collect and transport urine through almost 1.25 million nephrons in the kidneys.

Q83. If loop of Henle were absent from mammalian nephron which one of the following is to be expected?

  • A. There will be no urine formation.
  • B. There will be hardly any change in the quality and quantity of urine formed
  • C. The urine will be more concentrated
  • D. The urine will be more dilute

Explanation: Reabsorption is a process by which useful constituents of glomerular filtrate are returned into the blood streams. It occurs in convoluted tubules (proximal convoluted tubule) as well as loop of Henle. Basically loop of Henle, in association with vasa rectae, plays an important role in the counter current mechanism (the process which makes urine hypertonic, i.e., more concentrated).Therefore, if Henle’s loop was absent from mammalian nephron the urine will be more dilute.

Why the other options are wrong
  • A. Henle's loop and vasa recta play an important role in the concentration of urine. When the filtrate flows in the two limbs o Henle's loop, the flow is in opposite directions, i.e. Counter-current. Similarly, blood flows through the two limbs of the vasa recta in a countercurrent pattern.
  • B. Quality and quantity of the urine will be affected.
  • C. No urine will not be concentrated because loop of Henle plays a role in concentration of urine.

Q84. The haemoglobin of a human foetus

  • A. The hemoglobin of a human fetus has only 2 protein subunits instead of 4
  • B. The hemoglobin of a human fetus has a higher affinity for oxygen than that of an adult
  • C. The hemoglobin of a human fetus has a lower affinity for oxygen than that of an adult
  • D. Its affinity for oxygen is the same as that of an adult

Explanation: A. The hemoglobin of a human fetus has only 2 protein subunits instead of 4: This statement is not accurate. Hemoglobin, in both fetuses and adults, consists of four protein subunits. The structure of hemoglobin remains consistent in this regard.B. The hemoglobin of a human fetus has a higher affinity for oxygen than that of an adult:This statement is accurate. Fetal hemoglobin (HbF) has a higher affinity for oxygen than adult hemoglobin (HbA). This higher affinity allows fetal hemoglobin to effectively extract oxygen from the mother's bloodstream, where the oxygen concentration is lower, and deliver it to the developing fetus.C. The hemoglobin of a human fetus has a lower affinity for oxygen than that of an adult:This statement is not accurate. As mentioned earlier, fetal hemoglobin actually has a higher affinity for oxygen compared to adult hemoglobin.D. Its affinity for oxygen is the same as that of an adult:This statement is not accurate. Fetal hemoglobin (HbF) and adult hemoglobin (HbA) have different oxygen affinities, with HbF having a higher affinity for oxygen.Correct Option: B. The hemoglobin of a human fetus has a higher affinity for oxygen than that of an adult.Summary: The correct option is B, which accurately states that fetal hemoglobin (HbF) has a higher affinity for oxygen compared to adult hemoglobin (HbA). This difference in oxygen affinity helps facilitate the efficient transfer of oxygen from the mother's bloodstream to the developing fetus during pregnancy. The other options either present inaccurate information or claim that the affinity for oxygen is the same in fetal and adult hemoglobin.

Why the other options are wrong
  • A. The hemoglobin of a human fetus has only 2 protein subunits instead of 4: This statement is not accurate. Hemoglobin, in both fetuses and adults, consists of four protein subunits. The structure of hemoglobin remains consistent in this regard.
  • C. The hemoglobin of a human fetus has a lower affinity for oxygen than that of an adult:This statement is not accurate. As mentioned earlier, fetal hemoglobin actually has a higher affinity for oxygen compared to adult hemoglobin.
  • D. Its affinity for oxygen is the same as that of an adult:This statement is not accurate. Fetal hemoglobin (HbF) and adult hemoglobin (HbA) have different oxygen affinities, with HbF having a higher affinity for oxygen.

Q85. Given the reaction: C3H8 + 5O2 → 3CO2 + 4H2O At STP , how many litres of O2 are needed to completely burn 5.0 litres of C3H8?

  • A. 5
  • B. 10
  • C. 10.5
  • D. 15
  • E. 25

Explanation: Consider that no. of moles of reactants = volume of the reactants.As the molar ratio between C3H6 and O2 is 1:5, the volume ratio is also the same. For 1L of C3H6 we need 5L of O2. Since the volume of C3H6 is 5L now, to burn this, we require 25L of O2.All other options are incorrect because they do not follow the exact mole-volume relationship required in this case.

Why the other options are wrong

    Q86. What is the product of both fermentation reactions and fractional distillation?

    • A. An ester
    • B. An acid
    • C. An alcohol
    • D. A soap
    • E. As base

    Explanation: Ethyl alcohol can be obtained by fermentation of starch, fermentation of molasses and fractional distillation of pyroligneous acid (obtained through destructive distillation of wood) gives Methyl alcohol.

    Why the other options are wrong
    • A. Esters are made by the reaction of a carboxylic acid with an alcohol.
    • B. Non metal oxide + Water - > Acids Example: Carbon dioxide + water - > carbonic acid.
    • D. Reaction of carboxylate salt with fat gives soap.
    • E. Bases are prepared by the direct union of a metal with oxygen.

    Q87. For the reaction: N2 + 3H2 ⇌ 2NH3 .The production of NH3 will be favored at:

    • A. High pressure and catalyst
    • B. Low pressure only
    • C. Low pressure and catalyst
    • D. High pressure only
    • E. Catalyst only

    Explanation: The forward reaction forms fewer moles of gas (4 → 2), so high pressure shifts equilibrium toward NH₃. A catalyst increases the reaction rate but does not change equilibrium position. Therefore, maximum ammonia production is achieved using high pressure along with a catalyst.

    Why the other options are wrong
    • B. To determine the favored conditions, you can apply Le Chatelier's Principle. Increasing pressure favors the side with fewer moles of gas. Since there are fewer moles on the right (2 moles of NH3) compared to the left (4 moles of N2 and 6 moles of H2), higher pressure would favor the production of NH3. There this option is not correct.
    • C. To determine the favored conditions, you can apply Le Chatelier's Principle. Increasing pressure favors the side with fewer moles of gas. Since there are fewer moles on the right (2 moles of NH3) compared to the left (4 moles of N2 and 6 moles of H2), higher pressure would favor the production of NH3. Therefore this option is not correct.
    • D. To determine the favored conditions, you can apply Le Chatelier's Principle. Increasing pressure favors the side with fewer moles of gas. Since there are fewer moles on the right (2 moles of NH3) compared to the left (4 moles of N2 and 6 moles of H2), higher pressure would favor the production of NH3.
    • E. To determine the favored conditions, you can apply Le Chatelier's Principle. Increasing pressure favors the side with fewer moles of gas. Since there are fewer moles on the right (2 moles of NH3) compared to the left (4 moles of N2 and 6 moles of H2), higher pressure would favor the production of NH3. Therefore this option is not correct.

    Q88. What volume in dm3 of KCl is obtained in the following equation if the volume of KCIO3 at the beginning of the reaction is 20 dm3? 2KClO3 → 2KCl + 3O2

    • A. 2 dm3
    • B. 74.5 dm3
    • C. 50 dm3
    • D. 40 dm3
    • E. 20 dm3

    Explanation: To determine the volume of KCl obtained in the given equation, we need to know the stoichiometric ratio between KCIO3 and KCl. From the balanced equation: 2KClO3 → 2KCl + 3O2 We can see that for every 2 moles of KCIO3, we obtain 2 moles of KCl. Therefore, the ratio is 1:1. Given that the volume of KCIO3 at the beginning of the reaction is 20 dm3, and the stoichiometric ratio is 1:1, the volume of KCl obtained will also be 20 dm3. Therefore, the volume of KCl obtained in the given equation is 20 dm3.

    Why the other options are wrong
    • A. This option is incorrect as it assumes a different stoichiometric ratio. The balanced equation shows a 1:1 ratio between KClO3 and KCl, not a ratio that would result in 2 dm3.
    • B. This option is incorrect because it does not respect the stoichiometric 1:1 ratio. The volume should match the initial KClO3 volume of 20 dm3.
    • C. This option is incorrect as it suggests an incorrect stoichiometric calculation. The correct ratio of 1:1 leads to an equal volume of KCl as the initial volume of KClO3.
    • D. This option is incorrect as it doubles the expected volume without justification. The stoichiometric ratio is 1:1, resulting in a volume equal to the initial KClO3 volume.

    Q89. Amylopectin has _ linkage.

    • A. α 1 - 4 glycosidic
    • B. β 1 - 4 and 1 - 6 glycosidic
    • C. α 1-4 and α 1 - 6 glycosidic
    • D. β 1 - 4 glycosidic

    Explanation: Amylopectin has both α 1-4 and 1 - 6 glycosidic bond linkages.

    Why the other options are wrong
    • A. This option is partially correct. Amylopectin contains α 1-4 glycosidic linkages in its linear chains, but it also includes branching linkages, which are not covered by this option alone.
    • B. This option is incorrect. Amylopectin is composed of α glucoses, not β glucoses, and therefore does not contain β glycosidic linkages.
    • D. This option is incorrect because amylopectin is made up of α-glucose units and does not contain β linkages. It lacks β 1-4 glycosidic bonds entirely.

    Q90. The formula for phitkari is?

    • A. K2SO4.Al2(SO4)3.24H2O
    • B. K2SO4.Cr2(SO4)3.24H2O
    • C. (NH4)2SO4.Al2(SO4)3.24H2O
    • D. (NH4)2SO4.Cr2(SO4)3.24H2O

    Explanation: The correct formula for phitkari, also known as Alum, is K2SO4.Al2(SO4)3.24H2O. This form of alum is often used in water purification, as a mordant in dyeing, and in various cosmetic applications. The other options represent different types of alum or similar double salts, but they are not typically referred to as phitkari.

    Why the other options are wrong
    • B. This formula represents Potassium Chromium Sulfate Dodecahydrate, which is not commonly referred to as phitkari and is generally used in tanning and dyeing.
    • C. This formula represents Ammonium Aluminum Sulfate Dodecahydrate, also known as Ammonium Alum, which is used in baking and as a flame retardant.
    • D. This formula represents Ammonium Chromium Sulfate Dodecahydrate, which is not commonly known as phitkari and is used in industrial applications.

    Q91. IUPAC name of the compound (CH3)2-CH-CH(C2H5)-C(CH3)3 is :

    • A. 3-ethyl-2,2,4-trimethylpentane
    • B. 3-ethyl-2,2,4-trimethylpentene
    • C. 3-ethyl-2,4-dimethylpentane
    • D. 4-ethyl-3-methylhexane
    • E. 3-ethyl-2,2-dimethylpentane

    Explanation: The correct IUPAC name for the compound is 3-ethyl-2,2,4-trimethylpentane. The numbering of the carbon chain begins from the end closest to the first substituent, ensuring the longest chain includes five carbon atoms (pentane). The substituents are three methyl groups (at carbons 2, 2, and 4) and one ethyl group (at carbon 3). This configuration is described by '3-ethyl-2,2,4-trimethylpentane'.Other options are incorrect because they either suggest the presence of a double bond ('pentene'), a miscount of the longest carbon chain ('hexane'), or an incorrect number of substituents at specified positions, failing to match the given molecular structure.

    Why the other options are wrong
    • B. 3-ethyl-2,2,4-trimethylpentene suggests an alkene with a double bond, indicated by 'pentene'. However, the given compound is a saturated alkane, not an alkene, as it lacks a double bond.
    • C. 3-ethyl-2,4-dimethylpentane describes a compound with only two methyl groups at positions 2 and 4, missing the additional methyl group required at position 2 to match the given structure.
    • D. 4-ethyl-3-methylhexane suggests a six-carbon parent chain ('hexane'), which does not correspond to the longest chain in the given compound, incorrectly identifying the main chain length.
    • E. 3-ethyl-2,2-dimethylpentane indicates only two methyl groups at the second carbon, but the given compound requires an additional methyl group at the fourth carbon, making this option incorrect.

    Q92. (HCHO)nH20 is the chemical formula for?

    • A. Formic acid
    • B. Paraformaldehyde
    • C. α-methyl propionaldehyde
    • D. Propionic acid

    Explanation: The compound (HCHO)nH₂O is known as paraformaldehyde. It is a polymer of formaldehyde, formed when multiple formaldehyde molecules undergo polymerization. This results in a series of repeating units, represented by (HCHO)n, with water (H₂O) being part of its stabilization in the polymer form. Options A, C, and D are incorrect because their chemical formulas do not match the structure of paraformaldehyde. Formic acid (Option A) is a simple carboxylic acid, α-methyl propionaldehyde (Option C) is an aldehyde with a different structure, and propionic acid (Option D) is another carboxylic acid.

    Why the other options are wrong
    • A. Formic acid has the chemical formula CH₂O₂, which does not match the given formula. It is a simple carboxylic acid, not a polymer.
    • C. α-methyl propionaldehyde has the chemical formula C₄H₈O. It is an aldehyde, not a polymer of formaldehyde.
    • D. Propionic acid has the chemical formula C₃H₆O₂, which is a carboxylic acid and does not match the given formula.

    Q93. A dipolar charged but overall electrically neutral ion is called:

    • A. Zwitterion
    • B. Unit electron
    • C. Cation
    • D. Anion

    Explanation: A zwitterion is a special type of ion that has both positive and negative charges in different parts of the molecule. This allows it to maintain an overall neutral charge, which is why it fits the description of a dipolar charged but overall electrically neutral ion. Amino acids often exist as zwitterions in biological systems. On the other hand, a unit electron is simply a single elementary charge with a negative value, a cation is positively charged, and an anion is negatively charged. None of these options have both charges simultaneously, so they cannot be considered zwitterions.

    Why the other options are wrong
    • B. A unit electron refers to an elementary charge, which carries a single negative charge. It does not have both positive and negative charges simultaneously, hence it is not a zwitterion.
    • C. A cation is an ion that carries a net positive charge. It does not possess a negative charge, so it cannot be considered a zwitterion.
    • D. An anion is an ion with a net negative charge. It does not have a positive charge, thus it is not a zwitterion.

    Q94. Reaction of Aldehydes with the Tollen's reagent results in the formation of _?

    • A. Red precipitate
    • B. Yellow precipitate
    • C. Silver mirror
    • D. Brick red precipitate

    Explanation: Tollen’s reagent is an alkaline solution of ammoniacal silver nitrate; the reduction of silver ions in the Tollen’s reagent results in a metallic silver.

    Why the other options are wrong
    • A. The reaction of aldehydes with Tollen's reagent does not result in the formation of a red precipitate. Instead, Tollen's reagent is used to test for the presence of aldehydes in a solution based on the formation of a silver mirror.
    • B. The reaction of aldehydes with Tollen's reagent also does not form a yellow precipitate. Again, the characteristic reaction of Tollen's reagent with aldehydes is the formation of a silver mirror.
    • D. The formation of a brick red precipitate is not associated with the reaction of aldehydes with Tollen's reagent. Instead, brick red precipitates can be formed in various chemical reactions involving different compounds, but they are not relevant to the Tollen's reagent test for aldehydes.

    Q95. Oxidation Number of all the elements in the free state is?

    • A. Unity
    • B. Positive
    • C. Zero
    • D. Negative

    Explanation: The oxidation number of an element in its free state is always zero.

    Why the other options are wrong
    • A. "Unity" means one or being in the state of one. In the context of oxidation numbers, this option does not apply to the oxidation states of elements in the free state.
    • B. "Positive" refers to a value greater than zero. In the free state, most elements do not have positive oxidation numbers because they typically have zero oxidation numbers. However, some elements can exhibit positive oxidation numbers in certain chemical compounds or ions.
    • D. "Negative" refers to a value less than zero. In the free state, elements do not generally have negative oxidation numbers.

    Q96. The strength of London forces depends on the size of:

    • A. Electrons.
    • B. Electronic cloud.
    • C. Lone pair on an atom
    • D. Poles of atoms

    Explanation: The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.

    Why the other options are wrong
    • A. This is not a corect option.The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.
    • C. This is not a correct option. .The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.
    • D. This is not a corect option. The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.

    Q97. The number of electrons present in n = 2, l = 1 and m = -1, 0, +1 are:

    • A. 6
    • B. 2
    • C. 8
    • D. 10
    • E. 18

    Explanation: n is the principal quantum number and indicates the number of shells. n = 2 indicates that the second shell is being discussed. l is the azimuthal quantum number and indicates the number of subshells. l = 0 means s subshell, l = 1 means p subshell, and so on. m is the magnetic quantum number and indicates the orientation of orbitals in the subshells. m ranges from -1 to +1 through 0. Since m = -1, 0, +1, this means that all three sub-orbitals; 2px, 2py, 2pz are taken into consideration. Since all of these have 2 electrons each, the total number of electrons in them is 6.

    Why the other options are wrong
    • B. Incorrect. This does not account for all the possible electrons in the specified sub-orbitals.
    • C. Incorrect. This number is too high considering the specific quantum numbers provided.
    • D. Incorrect. This number is also too high given the quantum numbers mentioned in the question.
    • E. Incorrect. This number is way too high for the specified quantum numbers.

    Q98. If the difference between electronegativity values between two atoms is less than 1.7 , the bond is necessarily:

    • A. Ionic
    • B. Covalent
    • C. Electrovalent
    • D. Polar
    • E. Non-polar

    Explanation: If the electronegative difference is >1.7 then its nature is ionic and <1.7 then its nature is covalent and if its equal to 1.7 then nature of bond will be 50% ionic and 50% covalent. As here, it is less than 1.7, nature is covalent.

    Why the other options are wrong
    • A. A bond is considered ionic if the electronegativity difference is greater than 1.7. Since the difference here is less than 1.7, it is not ionic.
    • C. Electrovalent is another term for ionic bonds, which occur when the electronegativity difference is greater than 1.7, not less.
    • D. A polar covalent bond occurs when the electronegativity difference is between 0.5 and 1.7. While this could be true, it does not specifically address whether the bond is covalent or ionic.
    • E. Non-polar covalent bonds occur when the electronegativity difference is very small, typically less than 0.5. This does not address the covalent nature of a bond with a difference less than 1.7.

    Q99. Which one of the following has the lowest % ionic character?

    • A. CCl4
    • B. BCl3
    • C. BeCl2
    • D. LiCl
    • E. HCl

    Explanation: Electronegativity increases as we go from left to right in a period. So, the electronegativity difference between elements and chlorine decreases. Ionic character decreases with a decrease in the value of electronegativity difference between elements. thus the correct order is: CCl4<BCl3<BeCl2<LiCl.

    Why the other options are wrong
    • B. BCl3 has a higher % ionic character than CCl4 due to a slightly greater electronegativity difference between boron and chlorine.
    • C. BeCl2 exhibits significant ionic character as beryllium and chlorine have a moderate electronegativity difference, leading to partial ionic bonding.
    • D. LiCl is primarily ionic as lithium and chlorine have a large electronegativity difference, resulting in a compound with high ionic character.
    • E. HCl has a noticeable ionic character due to the significant electronegativity difference between hydrogen and chlorine, though less than that of LiCl.

    Q100. Consider the following reactionN2 (g) + O2 (g) < - > 2NO (g) Kc - 0.1 at 2000 CIf the original concentration of N2 and O2 were 0.1 M each. Calculate the concentrations of NO at equilibrium.

    • A. 0.028 M
    • B. 0.0012 M
    • C. 0.18 M
    • D. 0.0018 M
    • E. 0.002 M

    Explanation: Explanation is given below.

    Why the other options are wrong
    • B. Kc = [NO]^2 / ([N2] * [O2])Substituting Values0.1 = (2x)^2 / ((0.1-x) * (0.1-x))Solving for x * Take the square root of both sides: √0.1 = (2x) / (0.1 - x) 0.316 = (2x) / (0.1 - x) * Rearrange and solve for x: 0.316 * (0.1 - x) = 2x 0.0316 - 0.316x = 2x 0.0316 = 2.316x x ≈ 0.0136Calculating [NO] at Equilibrium[NO] = 2x = 2 * 0.0136 ≈ 0.0272 M, which is approximately 0.028 M.
    • C. Kc = [NO]^2 / ([N2] * [O2])Substituting Values0.1 = (2x)^2 / ((0.1-x) * (0.1-x))Solving for x * Take the square root of both sides: √0.1 = (2x) / (0.1 - x) 0.316 = (2x) / (0.1 - x) * Rearrange and solve for x: 0.316 * (0.1 - x) = 2x 0.0316 - 0.316x = 2x 0.0316 = 2.316x x ≈ 0.0136Calculating [NO] at Equilibrium[NO] = 2x = 2 * 0.0136 ≈ 0.0272 M, which is approximately 0.028 M.
    • D. Kc = [NO]^2 / ([N2] * [O2])Substituting Values0.1 = (2x)^2 / ((0.1-x) * (0.1-x))Solving for x * Take the square root of both sides: √0.1 = (2x) / (0.1 - x) 0.316 = (2x) / (0.1 - x) * Rearrange and solve for x: 0.316 * (0.1 - x) = 2x 0.0316 - 0.316x = 2x 0.0316 = 2.316x x ≈ 0.0136Calculating [NO] at Equilibrium[NO] = 2x = 2 * 0.0136 ≈ 0.0272 M, which is approximately 0.028 M.
    • E. Kc = [NO]^2 / ([N2] * [O2])Substituting Values0.1 = (2x)^2 / ((0.1-x) * (0.1-x))Solving for x * Take the square root of both sides: √0.1 = (2x) / (0.1 - x) 0.316 = (2x) / (0.1 - x) * Rearrange and solve for x: 0.316 * (0.1 - x) = 2x 0.0316 - 0.316x = 2x 0.0316 = 2.316x x ≈ 0.0136Calculating [NO] at Equilibrium[NO] = 2x = 2 * 0.0136 ≈ 0.0272 M, which is approximately 0.028 M.

    Q101. Matter changes from one state to another state on change in _.

    • A. Density
    • B. Pressure
    • C. Viscosity
    • D. All

    Explanation: The state of matter changes primarily due to variations in temperature and pressure. For instance, when solids are heated, they can melt into liquids, and liquids can vaporize into gases with further heating. Conversely, increasing pressure can compress gases into liquids and solids by reducing the space between particles. Therefore, pressure is a key factor in changing states of matter. Density and viscosity are properties of matter but they do not directly change its state.

    Why the other options are wrong
    • A. Density is a property that refers to the mass per unit volume of a substance and does not directly cause a change in the state of matter.
    • C. Viscosity describes a fluid's resistance to flow and does not directly affect the state of matter.
    • D. Not all these factors directly change the state of matter; only pressure and temperature do.

    Q102. The bonding pair of electrons are equally shared between the atoms in?

    • A. HF
    • B. HCl
    • C. H2O
    • D. H2

    Explanation: H2 forms a covalent bond with identical atoms, so the electrons in the bond must be shared equally.

    Why the other options are wrong
    • A. In hydrogen fluoride (HF), the bonding pair of electrons is not equally shared between the atoms. Fluorine is more electronegative than hydrogen, so it attracts the bonding electrons closer to itself, resulting in a polar covalent bond. As a result, HF has a partial positive charge on the hydrogen atom and a partial negative charge on the fluorine atom.
    • B. Similar to HF, in hydrogen chloride (HCl), the bonding pair of electrons is not equally shared between the atoms. Chlorine is more electronegative than hydrogen, leading to a polar covalent bond. HCl has a partial positive charge on the hydrogen atom and a partial negative charge on the chlorine atom.
    • C. In water (H2O), the bonding pair of electrons is also not equally shared between the atoms. Oxygen is more electronegative than hydrogen, causing the oxygen atom to pull the electrons towards itself, resulting in a polar covalent bond. Water has a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom.

    Q103. The total of all the possible kind of energies in a system is called:

    • A. Total energy
    • B. Kinetic Energy
    • C. Potential Energy
    • D. Internal Energy

    Explanation: Internal energy is defined as the total energy of a closed system.

    Why the other options are wrong
    • A. Total energy refers to the sum of all the different types of energies present in a system. This includes both kinetic energy and potential energy.
    • B. Kinetic energy is the energy possessed by an object due to its motion. The kinetic energy of an object depends on its mass and velocity and can be calculated using the formula: KE = 0.5 * m * v^2, where m is the mass of the object and v is its velocity.
    • C. Potential energy is the energy stored in an object or system based on its position or configuration. There are different types of potential energy, such as gravitational potential energy, elastic potential energy, and chemical potential energy.

    Q104. Energy is absorbed?

    • A. In bond breaking
    • B. In endothermic reactions
    • C. In bond formation
    • D. Both Options A and B are correct

    Explanation: Breaking bonds requires adding energy, the opposite process of forming new bonds always releases energy. Bond breaking is an endothermic process while bond formation is an exothermic process.

    Why the other options are wrong
    • A. When chemical bonds are broken during a reaction, energy is absorbed from the surroundings. This process requires energy input to break the existing bonds, and this absorbed energy is stored in the newly formed products.
    • B. Endothermic reactions are chemical reactions that require energy input to proceed. In these reactions, energy is absorbed from the surroundings, usually in the form of heat. As a result, the temperature of the surroundings decreases, and the products of the reaction have higher energy content than the reactants.
    • C. When new chemical bonds are formed during a reaction, energy is released or given off to the surroundings. This energy is the result of potential energy being converted to kinetic energy as the atoms or molecules come together and form stable chemical bonds.

    Q105. Which of the following has the maximum number of unpaired d electrons?

    • A. Mg 2+
    • B. Ti 3+
    • C. V 3+
    • D. Fe 2+

    Explanation: The electron configuration for Fe2+ will be 1s2 2s2 2p6 3s2 3p6 4s2 3d4 because it has lost two electrons.All four electrons in d-orbital are unpaired.The Magnesium ion electron configuration will be 1s22s22p6.For the V3+, called the Vanadium ion, we remove one electron from 3d3 and two from the 3d2 leaving us with: 1s2 2s2 2p6 3s2 3p6 3d2.Electronic configuration of Ti3+ is [Ar] 3d1,which means it only has 1 unpaired electron.

    Why the other options are wrong
    • A. Mg²⁺: Magnesium (Mg) has an atomic number of 12. Mg²⁺ loses two electrons, resulting in the configuration 1s² 2s² 2p⁶. It has no d electrons, so it has zero unpaired electrons.
    • B. Ti³⁺: Titanium (Ti) has an atomic number of 22. Ti³⁺ loses three electrons, resulting in the configuration [Ar] 3d¹. It has one unpaired d electron.
    • C. V³⁺: Vanadium (V) has an atomic number of 23. V³⁺ loses three electrons, resulting in the configuration [Ar] 3d². It has two unpaired d electrons.

    Q106. CH3CH2CH2COCH3 is the functional isomer of:

    • A. CH3CH2CH2CH2CHO
    • B. CH3CH2CH2CH2OH
    • C. CH3CH2COCH2CH3
    • D. CH3 - (CH)2 COCH2CH3

    Explanation: CH3CH2CH2COCH3 and CH3CH2CH2CH2CHO have the same number of atoms for the constituent elements, Carbon, Oxygen, and Hydrogen. However, the second requirement of a 'Functional Isomer' is that the functional groups, of the two isomers, must be different and since, in this case, we have a ketone functional group and an aldehyde functional, both compounds can be positively termed as 'Functional Isomers' of each other.Thus, option A is correct.

    Why the other options are wrong
    • B. This compound is an alcohol and does not have the same molecular formula as the given compound, hence they cannot be isomers.
    • C. This compound is a ketone like the given compound. Although they are positional isomers (same functional group, different position), they are not functional isomers.
    • D. This compound also has a ketone functional group and is not a functional isomer, as it shares the same functional group with the given compound.

    Q107. 20 cm3 of a gaseous hydrocarbon was completely burnt in an excess of oxygen 60 cm3 of carbon dioxide and 40 cm3 of water vapours were formed, all volumes being measured at the same temperature and pressure. What is the formula of the hydrocarbon?

    • A. C2H6
    • B. C3H4
    • C. C3H6
    • D. C3H8
    • E. C4H10

    Explanation: The combustion of a hydrocarbon can be represented by the equation CₓHᵧ + (x + y/4)O₂ → xCO₂ + (y/2)H₂O. Given that 20 cm³ of the hydrocarbon produces 60 cm³ of CO₂ and 40 cm³ of H₂O, we can use the volume ratios to determine the stoichiometry. For each 20 cm³ of hydrocarbon, we obtain 60 cm³ of CO₂, indicating x = 3, and 40 cm³ of H₂O, indicating y = 4. Therefore, the formula is C₃H₄. Other options like C₂H₆, C₃H₆, C₃H₈, and C₄H₁₀ would result in different product volume ratios and do not satisfy the conditions given in the problem.

    Why the other options are wrong
    • A. Incorrect. The volumes of CO2 and H2O produced do not match the stoichiometry of C2H6. This would produce a different ratio of volumes.
    • C. Incorrect. This formula would produce different volumes of CO2 and H2O that do not match the given data.
    • D. Incorrect. The stoichiometry of C3H8 would result in a different ratio of product volumes than provided.
    • E. Incorrect. The volumes produced from C4H10 combustion do not align with the data, indicating a different formula.

    Q108. The colour of methyl orange in base is?

    • A. Red
    • B. Yellow
    • C. Orange
    • D. Pink

    Explanation: Methyl orange is an indicator that changes color based on the pH of the solution. In an acidic environment, it appears red, while in a basic environment, it turns yellow. Option B is correct because the color change to yellow indicates the presence of a base. Option A is incorrect as red is the color in an acidic solution. Option C is incorrect because methyl orange does not transition through an orange phase; it moves from red to yellow. Option D is incorrect as pink is not a color change associated with methyl orange, but rather with phenolphthalein in basic conditions.

    Why the other options are wrong
    • A. Methyl orange turns red in an acidic solution, not in a basic solution.
    • C. Methyl orange does not exhibit an orange color in any solution; its transition is between red and yellow.
    • D. Pink is the color change associated with phenolphthalein in basic solutions, not methyl orange.

    Q109. GN Lewis described which one of the following bonds?

    • A. Ionic bond
    • B. Covalent bond
    • C. Coordinate covalent bond
    • D. All of the above

    Explanation: G.N. Lewis is renowned for his work on the nature of chemical bonding, particularly the sharing of electron pairs between atoms, which forms the basis of covalent bonds. His theories extend to both ordinary covalent bonds and coordinate covalent bonds. While ionic bonds involve electron transfer and are not the primary focus of Lewis's theories, his work laid the groundwork for understanding chemical bonding as a whole. Therefore, 'All of the above' is the correct answer, as it encompasses the types of bonds Lewis described.

    Why the other options are wrong
    • A. An ionic bond involves the transfer of electrons from one atom to another, resulting in the formation of ions. G.N. Lewis primarily focused on electron pair sharing in covalent bonds rather than ionic bonds.
    • B. G.N. Lewis is well-known for his description of covalent bonds, where atoms share electron pairs to attain stability. His work led to the concept of the Lewis structure, which represents covalent bonds.
    • C. A coordinate covalent bond, also known as a dative bond, is a type of covalent bond where both electrons in the shared pair come from the same atom. Lewis's theory also encompasses this type of bond.

    Q110. Which of the following compounds shows maximum Hydrogen Bonding?

    • A. CH3OH
    • B. CH3CH2OH
    • C. C6H5OH
    • D. C6H11OH

    Explanation: Phenol has a benzene ring that can participate in pi-bonding (π-bonding) with other electron-rich aromatic systems in addition to forming hydrogen bonds. This makes it more likely to show stronger hydrogen bonding compared to the other options.

    Why the other options are wrong
    • A. Methanol (CH3OH) can form hydrogen bonds. It contains one hydroxyl group (-OH), which can act as a hydrogen bond donor and acceptor.
    • B. Ethanol (CH3CH2OH) can also form hydrogen bonds. Similar to methanol, it contains one hydroxyl group (-OH) that enables it to participate in hydrogen bonding.
    • D. Cyclohexanol (C6H11OH) can form hydrogen bonds too. It contains one hydroxyl group (-OH) that can engage in hydrogen bonding.

    Q111. Which of the following solvents favor SN2 reactions?

    • A. Water
    • B. Ammonia
    • C. Carbon tetrachloride
    • D. Acetic acid

    Explanation: The correct answer is Carbon tetrachloride, which is a non-polar solvent that does not stabilize ions and thus allows for a more favorable environment for SN2 reactions. In SN2 mechanisms, the nucleophile attacks the substrate in a single concerted step, and polar protic solvents like water, ammonia, and acetic acid can hinder this process by stabilizing the transition state or the leaving group, making them less favorable for such reactions.In contrast, polar aprotic solvents (like carbon tetrachloride) do not solvate the nucleophile as strongly, allowing it to remain reactive and effectively participate in the nucleophilic substitution process.

    Why the other options are wrong
    • A. Water is a polar protic solvent that can stabilize cations but is not ideal for SN2 reactions, which prefer polar aprotic solvents that do not form strong hydrogen bonds.
    • B. Ammonia is a polar protic solvent, similar to water, and is not the best choice for SN2 reactions due to its ability to stabilize cations rather than facilitate nucleophilic attack.
    • D. Acetic acid is a polar protic solvent that can stabilize cations and slow down the SN2 reaction process, making it less favorable for this type of reaction.

    Q112. The range of pH below _ and above _ of soil represent its sterilIty.

    • A. 5....10
    • B. 10....15
    • C. 3....10
    • D. 10....3
    • E. 5....3

    Explanation: pH below 3 and pH above 10 results in soil infertility. Hence the answer is C.

    Why the other options are wrong
    • A. Option A is incorrect as pH below 5 till 3 is suitable for soil fertility.
    • B. Option B is incorrect as pH below 10 is suitable for soil fertility.
    • D. Option D is incorrect as pH below 10 and above 3 is suitable for soil fertility.
    • E. Option E is incorrect as pH below 5 and above 3 is also suitable for soil fertility.

    Q113. Consider NaCl produced in the equation: FeCl3+ NaOH → Fe(OH)3 + NaCl 175.5g of NaCl was dissolved in water to make a liter of solution, the molarity would be:

    • A. 0.1 M
    • B. 3 M
    • C. 8 M
    • D. 12 M
    • E. 16 M

    Explanation: Molarity = number of moles/volume in dm3 or liters 175.5 g make up 3 moles of NaCl 175.5/58.5 = 3 mol That means 3 mole of NaCl is dissolved in 1 liter of solution that makes the NaCl solution 3M.

    Why the other options are wrong

      Q114. Harmful and undesirable reaction of a metal when exposed to the atmosphere or any chemical agent is known as:

      • A. Allotropy
      • B. Electroplating
      • C. Collision
      • D. Cracking
      • E. Corrosion

      Explanation: The harmful and desirable reaction which occurs due to oxidation of the metal exposed to the surrounding air is called corrosion.

      Why the other options are wrong
      • A. Option A is wrong as Allotropy is the phenomena exhibited by solids in which a crystalline solid or an element exists in more than 1 crystalline form e.g. allotropes of carbon are Graphite (hexagonal) and diamond (cubic).
      • B. Option B is wrong as electroplating is the method of deposition of a metal over another metal or substance in order to protect it from corrosion.
      • C. Option C is wrong as collision is the phenomena in which two objects strike one another with great force.
      • D. Option D is wrong as cracking is the phenomenon in which larger saturated hydrocarbon molecules are broken down into smaller hydrocarbon molecules, some of which can be unsaturated.

      Q115. Catenation is a process in which carbon shows the properties of:

      • A. Making single bond
      • B. Hybridization
      • C. Making chains or rings of carbon atoms
      • D. Isomerism
      • E. Breaking of bonds

      Explanation: Catenation is the process by which an atom is able to form a bond with another atom of its kind. Carbon possesses this ability hence is able to form ringed structures.

      Why the other options are wrong
      • A. Catenation is the process by which an atom is able to form a bond with another atom of its kind. Carbon possesses this ability hence is able to form ringed structures.Option A is incorrect as catenation is the property of forming all kinds of bonds with the same kind of atoms either single, double or triple.
      • B. Option B is incorrect as hybridization is the process in which atomic orbitals mix to form new hybrid orbitals suitable for the pairing of electrons to form chemical bonds.
      • D. Option D is incorrect as isomerism is the phenomena exhibited by organic compounds in which compounds have the same molecular formula but different structural formula.
      • E. Option E is incorrect as catenation does not involve breaking of bonds.

      Q116. Which of the following statements is true for Amorphous solids?

      • A. They possess symmetry
      • B. They are isotropic
      • C. They are anisotropic
      • D. They cleave along a particular direction
      • E. They have a definite shape

      Explanation: Amorphous solids are isotropic because their lack of long-range order results in uniform physical properties in all directions. This is in contrast to crystalline solids, which are anisotropic due to their orderly atomic structure. Amorphous solids do not possess symmetry and cannot cleave along particular planes because their particles are randomly arranged. Additionally, they do not exhibit a definite shape as their molecular structure does not form a regular lattice.

      Why the other options are wrong
      • A. Amorphous solids lack symmetry because their atomic arrangement is irregular, unlike crystalline solids which have a symmetrical, orderly pattern.
      • C. Anisotropic materials, like crystalline solids, have direction-dependent properties, which is not the case for amorphous solids.
      • D. Cleavage along specific directions is characteristic of crystalline solids due to their ordered structure. Amorphous solids break irregularly because of their random atomic arrangement.
      • E. Amorphous solids do not have a definite shape or form since their atoms are not arranged in a fixed, repeating pattern.

      Q117. Only two elements are present in:

      • A. Period 1
      • B. Period 2
      • C. Period 3
      • D. Period 4
      • E. Period 5

      Explanation: Period 1 of the periodic table consists of only two elements: hydrogen and helium. This is because the first electron shell (the 1s orbital) can hold a maximum of two electrons. In contrast, Periods 2 and 3 each have 8 elements, as they include the filling of s and p orbitals. Periods 4 and 5 have even more elements, 18 each, due to the inclusion of the d orbitals. Hence, the correct answer is Period 1, where only two elements are present.

      Why the other options are wrong
      • B. Period 2 contains 8 elements, as it fills both the 2s and 2p orbitals.
      • C. Period 3 also contains 8 elements, filling the 3s and 3p orbitals.
      • D. Period 4 contains 18 elements, including transition metals that fill the 3d orbitals.
      • E. Period 5 contains 18 elements, similar to Period 4, involving the filling of the 4d orbitals.

      Q118. If the reaction, P + Q → R + S, is described as being of zero-order with respect to P, it means that:

      • A. P is a catalyst in this reaction
      • B. No P molecules possess sufficient energy to react
      • C. The concentration of P does not change during the reaction
      • D. The rate of reaction is independent of the concentration of P
      • E. The rate of reaction is proportional to the concentration of Q

      Explanation: If the order of reaction with respect to P is 0 (zero), this means that the concentration of P doesn't affect the rate of reaction. Mathematically, any number raised to the power of zero (x0) is equal to 1. That means that that particular term disappears from the rate equation.

      Why the other options are wrong
      • A. P is a reactant in this reaction, not a catalyst. A catalyst is a substance that speeds up a reaction without being consumed, which is not the case for P.
      • B. This statement is incorrect because the reaction occurs, indicating that P molecules do possess sufficient energy for effective collisions and to form products.
      • C. While the rate is independent of P's concentration, the concentration of P actually decreases as it is consumed in the reaction.
      • E. This cannot be determined from the information given. The dependence on Q's concentration requires experimental data to establish the reaction order with respect to Q.

      Q119. The oxidation number of all the elements in the free state is:

      • A. 1
      • B. 3
      • C. 0
      • D. -1
      • E. -3

      Explanation: All the elements have an oxidation number of 0 in the free state.

      Why the other options are wrong
      • A. The oxidation number of 1 applies to elements in compounds where they typically lose or gain one electron, such as in Na+ or Cl-. In the free state, elements are neutral.
      • B. An oxidation number of 3 can be found in elements that typically gain or lose three electrons in compounds, such as Fe3+. However, in the free state, elements do not exhibit this behavior.
      • D. An oxidation number of -1 is typical for elements like halogens in compounds where they gain one electron, such as Cl-. Free state elements do not gain or lose electrons.
      • E. Elements with an oxidation number of -3 generally gain three electrons in compounds, such as nitrogen in NH3. In the free state, elements maintain a neutral charge.

      Q120. According to which phenomenon, "the properties of elements are the periodic function of their atomic number."

      • A. Mendeleev's periodic law
      • B. Newland's law of octaves
      • C. Dobereiner's triads
      • D. Lothar Meyer’s classification
      • E. Modern periodic law

      Explanation: The modern Periodic law can be stated as: “The physical and chemical properties of the elements are periodic functions of their atomic numbers”. The atomic number is equal to the number of electrons or protons in a neutral atom.

      Why the other options are wrong
      • A. Mendeleev formulated his periodic law based on atomic mass, not atomic number. He observed that the properties of elements are periodic functions of their atomic masses.
      • B. Newland's law was an early attempt to classify elements, stating that every eighth element had similar properties, based on increasing atomic mass, not atomic number.
      • C. Dobereiner grouped elements into triads based on similar chemical properties and atomic masses, not on atomic numbers.
      • D. Lothar Meyer arranged elements by increasing atomic weights, noting periodic trends in properties, but this was not based on atomic numbers.

      Q121. Comparative rates of diffusion of He and SO2 will be _.

      • A. 8
      • B. 2
      • C. 4
      • D. 16
      • E. 64

      Explanation: According to Graham's law of effusion, the rate of diffusion of a gas is inversely proportional to the square root of its molar mass. Therefore, the comparative rate of diffusion can be calculated using the formula: Rate of diffusion = √(M1/M2) Here, M1 is the molar mass of SO2 (64 g/mol), and M2 is the molar mass of He (4 g/mol). Plugging in these values gives: √(64/4) = √16 = 4. Therefore, the comparative rate of diffusion of helium to sulfur dioxide is 4. The incorrect options arise from not correctly applying the square root to the ratio of molar masses.

      Why the other options are wrong
      • A. This value results from an incorrect calculation of the square root of the molar mass ratio.
      • B. This is not the correct result of applying Graham's law to the given molar masses.
      • D. This is the square of the correct answer, not the result of the square root operation.
      • E. This value is a misinterpretation of the molar masses without applying the square root appropriately.

      Q122. The maximum possible number of electrons a shell 'n' can accommodate is given by:

      • A. n
      • B. n2
      • C. 2n2
      • D. n3
      • E. 3n2

      Explanation: The maximum number of electrons that can be in a shell is 2n2.

      Why the other options are wrong
      • A. The principal quantum number 'n' indicates the energy level of an electron shell but does not determine its electron capacity directly.
      • B. The formula n² gives the total number of orbitals in a shell but not the maximum number of electrons it can hold.
      • D. n³ is not a recognized formula in atomic theory for calculating electron capacity or orbital count.
      • E. 3n² is not a valid formula for determining electron capacity in atomic structure.

      Q123. IUPAC name of this is (CH3)2 - CH - CH (C2H5) - C(CH3)3 :

      • A. 3-ethyl-2,2,4-trimethylpentane
      • B. 4-ethyl-2,2,4-trimethylpentane
      • C. 5-ethyl-2,2,4-trimethylpentane
      • D. 2-ethyl-2,2,4-trimethylpentane
      • E. 1-ethyl-2,2,4-trimethylpentane

      Explanation: The IUPAC name for the given compound (CH3)2-CH-CH(C2H5)-C(CH3)3 is "3-ethyl-2,2,4-trimethylpentane." Here's how the name is derived:1. Identify the longest continuous carbon chain, which in this case is a five-carbon chain.2. Number the carbon chain to give the substituents the lowest possible locants. In this case, we start numbering from the end nearest to the ethyl group, so the ethyl group is located on carbon 3.3. Assign substituent names and locants. The methyl groups attached to carbon 2 and carbon 4 are called "2,2-dimethyl" and "2,4-dimethyl," respectively. The ethyl group attached to carbon 3 is named "ethyl."4. Combine all the parts to form the complete IUPAC name: "3-ethyl-2,2,4-trimethylpentane."Therefore, the compound (CH3)2-CH-CH(C2H5)-C(CH3)3 is named 3-ethyl-2,2,4-trimethylpentane.

      Why the other options are wrong
      • B. This name incorrectly places the ethyl group at position 4 instead of 3, which does not follow the IUPAC naming rule of assigning the lowest locant numbers to substituents.
      • C. This option incorrectly places the ethyl group at position 5, which is not possible as it is not the smallest locant for the ethyl group.
      • D. This name incorrectly places the ethyl group at position 2, which does not reflect the actual structure of the compound.
      • E. This option incorrectly places the ethyl group at position 1, which would not be correct as it does not match the structure of the compound.

      Q124. Metaboric acid when heated produces:

      • A. B2O3
      • B. HBO2
      • C. H2B4O7
      • D. H3BO3

      Explanation: This is the following solution:

      Why the other options are wrong
      • A. B2O3 is not formed directly from metaboric acid upon heating, but rather from further decomposition of boric acids. This option is incorrect for this stage of heating.
      • B. HBO2 is not the product of heating metaboric acid; it is an intermediate in the dehydration of boric acid. This option is incorrect.
      • D. H3BO3 is orthoboric acid, which is not formed by heating metaboric acid. This option is incorrect as it represents a different form of boric acid.

      Q125. Caster kellners cell evaporated has replaced _ because the Caster Kellner process evaporates_?

      • A. Gibbs diaphragm… mercury
      • B. Iron box… aluminium
      • C. Pyrites burners… oleum
      • D. Nelson's cell… chlorine

      Explanation: The Caster-Kellner cell, also known as the mercury cell, was introduced as a replacement for the Gibbs diaphragm cell. This change was primarily due to the Caster-Kellner process's efficiency in using mercury to produce chlorine and caustic soda through the electrolysis of saltwater. The process involves mercury, which acts as a cathode. Other options like the Iron box and Pyrites burners are not related to this process, and while Nelson's cell also produces chlorine, it does not utilize mercury in the same manner.

      Why the other options are wrong
      • B. This option is incorrect. The Caster-Kellner process is not related to the production or processing of aluminium.
      • C. This option is incorrect. Pyrites burners are used in the production of sulfuric acid, not related to the Caster-Kellner process.
      • D. This option is incorrect. The Nelson cell is another process for producing chlorine, but it does not involve the evaporation of mercury as in the Caster-Kellner process.

      Q126. Nitrogen dioxide decomposes on heating according to the following equation: 2NO2 (g) ⇌ 2NO (g)+ O2 (g) When 4 moles of nitrogen dioxide were put into a 1 dm3 container and heated to a constant temperature, the equilibrium mixture contained 0.8 moles of oxygen. What is the numerical value of the equilibrium constant, Kc, at the temperature of the experiment?

      • A. Option A
      • B. Option B
      • C. Option C
      • D. Option D

      Explanation: To find the numerical value of the equilibrium constant, Kc, we need to use the equilibrium concentrations of the reactants and products.According to the given information, we start with 4 moles of nitrogen dioxide (NO2) in a 1 dm^3 container. This means the initial concentration of NO2 is 2.4 moles/1 dm^3 = 2.4 M.At equilibrium, we have 0.8 moles of oxygen (O2) in the 1 dm^3 container. The equilibrium concentration of O2 is therefore 0.8 M.Since the stoichiometry of the balanced equation is 2NO2 ⇌ 2NO + O2, the equilibrium concentration of nitrogen monoxide (NO) will also be 2 times the concentration of O2, which is 2 x 0.8 M = 1.6 M.Now we can write the expression for the equilibrium constant, Kc:Kc = [NO]2 [O2] / [NO2]2Kc = (1.6 M)2 * (0.8 M) / (2.4 M)2This is numerical so it can only have one correct option.

      Why the other options are wrong
      • A. To find the numerical value of the equilibrium constant, Kc, we need to use the equilibrium concentrations of the reactants and products.According to the given information, we start with 4 moles of nitrogen dioxide (NO2) in a 1 dm^3 container. This means the initial concentration of NO2 is 2.4 moles/1 dm^3 = 2.4 M.At equilibrium, we have 0.8 moles of oxygen (O2) in the 1 dm^3 container. The equilibrium concentration of O2 is therefore 0.8 M.Since the stoichiometry of the balanced equation is 2NO2 ⇌ 2NO + O2, the equilibrium concentration of nitrogen monoxide (NO) will also be 2 times the concentration of O2, which is 2 x 0.8 M = 1.6 M.Now we can write the expression for the equilibrium constant, Kc:Kc = [NO]2 [O2] / [NO2]2Kc = (1.6 M)2 * (0.8 M) / (2.4 M)2
      • B. To find the numerical value of the equilibrium constant, Kc, we need to use the equilibrium concentrations of the reactants and products.According to the given information, we start with 4 moles of nitrogen dioxide (NO2) in a 1 dm^3 container. This means the initial concentration of NO2 is 2.4 moles/1 dm^3 = 2.4 M.At equilibrium, we have 0.8 moles of oxygen (O2) in the 1 dm^3 container. The equilibrium concentration of O2 is therefore 0.8 M.Since the stoichiometry of the balanced equation is 2NO2 ⇌ 2NO + O2, the equilibrium concentration of nitrogen monoxide (NO) will also be 2 times the concentration of O2, which is 2 x 0.8 M = 1.6 M.Now we can write the expression for the equilibrium constant, Kc:Kc = [NO]2 [O2] / [NO2]2Kc = (1.6 M)2 * (0.8 M) / (2.4 M)2
      • C. To find the numerical value of the equilibrium constant, Kc, we need to use the equilibrium concentrations of the reactants and products.According to the given information, we start with 4 moles of nitrogen dioxide (NO2) in a 1 dm^3 container. This means the initial concentration of NO2 is 2.4 moles/1 dm^3 = 2.4 M.At equilibrium, we have 0.8 moles of oxygen (O2) in the 1 dm^3 container. The equilibrium concentration of O2 is therefore 0.8 M.Since the stoichiometry of the balanced equation is 2NO2 ⇌ 2NO + O2, the equilibrium concentration of nitrogen monoxide (NO) will also be 2 times the concentration of O2, which is 2 x 0.8 M = 1.6 M.Now we can write the expression for the equilibrium constant, Kc:Kc = [NO]2 [O2] / [NO2]2Kc = (1.6 M)2 * (0.8 M) / (2.4 M)2

      Q127. CH ≡ CH + 2AgNO3 -> AgC ≡ CAg + 2HNO3 represents _ property of acetylene.

      • A. Basic
      • B. Acidic
      • C. Dehydrating
      • D. Physical
      • E. None of the above

      Explanation: Acetylene is a known weak acid as it can be seen when dissolved in silver nitrate it can give off its two hydrogen ions - thus acting as a acid.

      Why the other options are wrong
      • A. Acetylene, being a terminal alkyne, does not exhibit basic properties. Instead, it shows slightly acidic behavior due to the presence of hydrogen atoms bonded to sp hybridized carbon.
      • C. The reaction does not involve the removal of water, thus it does not demonstrate any dehydrating property of acetylene.
      • D. This reaction is a chemical transformation indicating the acidic property of acetylene, not a physical property.
      • E. This option is incorrect because the acidic property of acetylene is correctly identified in Option B.

      Q128. The stability of carbonium ions following the order:

      • A. A. Methyl > Ethyl > Isopropyl (secondary) > Tertiarybutyl
      • B. B. Tertiarybutyl > Isopropyl (secondary) > Ethyl > Methyl
      • C. C. Isopropyl (secondary) > Tertiarybutyl > Ethyl > Methyl
      • D. D. Ethyl > Methyl > Isopropyl (secondary) > Tertiarybutyl
      • E. E. Methyl > Isopropyl (secondary) > Tertiarybutyl > Ethyl

      Explanation: The stability of carbonium ions increases with the number of alkyl groups attached to the positively charged carbon. This is because alkyl groups provide electron-donating effects that help stabilize the positive charge. Therefore, tertiary carbonium ions, with three alkyl groups, are more stable than secondary and primary ions. Thus, the correct order of stability is: Tertiarybutyl > Isopropyl (secondary) > Ethyl > Methyl. Options A, C, D, and E incorrectly represent the stability order by either misplacing the tertiary ion or suggesting a misleading trend.

      Why the other options are wrong
      • A. This order is incorrect because primary carbonium ions like methyl are less stable than secondary and tertiary carbonium ions.
      • C. This order incorrectly places secondary carbonium ions above tertiary ones, which are more stable.
      • D. This order is incorrect because it does not reflect the correct stability trend based on the number of alkyl groups.
      • E. This order is incorrect as it places a primary carbonium ion above tertiary and secondary ones.

      Q129. _ is used as a preservative for life specimens.

      • A. H2SO4
      • B. Ammonia
      • C. Methanol
      • D. NaOH
      • E. Formalin

      Explanation: Formalin is widely used for the preservation of biological specimens due to its ability to fix tissues, making them resistant to decay. It works by crosslinking proteins, which helps maintain the structure of cells and tissues. Formalin also has antiseptic properties, preventing microbial growth. The other options, such as H2SO4, ammonia, methanol, and NaOH, are not suitable for preservation as they can damage tissues or fail to effectively preserve cellular structures.

      Why the other options are wrong
      • A. H2SO4 (sulfuric acid) is a strong acid and a dehydrating agent. It is not suitable for preserving life specimens as it can cause severe tissue damage.
      • B. Ammonia is a toxic chemical that can be corrosive to tissues, making it unsuitable for preserving biological specimens.
      • C. Methanol is generally not recommended for preserving specimens for molecular studies, as it can negatively affect DNA preservation, particularly in insects.
      • D. NaOH (sodium hydroxide) is a strong base used for cleaning and disinfection, but it is not used for preserving biological specimens due to its protein and nucleic acid degrading properties.

      Q130. EDTA ion is a _ ligand.

      • A. Monodentate
      • B. Bidentate
      • C. Tridentate
      • D. Polydentate
      • E. None of the above

      Explanation: EDTA ion is polydentate. Ethylenediaminetetraacetic acid (EDTA) is an amino polycarboxylic acid with the formula [CH2N(CH2CO2H)2]2. This white, water-soluble solid is widely used to bind to iron and calcium ions. It binds these ions as a hexadentate ("six-toothed") chelating agent.

      Why the other options are wrong
      • A. A monodentate ligand donates only one pair of electrons to a central metal atom. EDTA is not monodentate because it can donate more than one pair of electrons.
      • B. A bidentate ligand can donate two pairs of electrons to a central metal atom. However, EDTA can donate more than two pairs of electrons, making it more than bidentate.
      • C. A tridentate ligand donates three pairs of electrons to a central metal atom. EDTA is capable of donating more than three pairs, so it is not tridentate.
      • E. This option is incorrect because the correct answer is Option D, which states that EDTA is a polydentate ligand.

      Q131. Sulphur-16 gets its stabilization by gaining 2 electron to become equal to:

      • A. Neon
      • B. Argon
      • C. Helium
      • D. Krypton

      Explanation: Option B is correct since sulfur-16 after gaining two electrons possesses 18 electrons and attains the stable electronic configuration of argon that also contains 18 electrons. Stability is gained by attaining the stable electronic configuration of a noble gas.Option A is incorrect since neon has 10 electrons whereas sulfur ion has 18.Option C is incorrect since helium has two electrons and sulfur ion has 18.Option D is incorrect since krypton has 36 electrons whereas, sulfur ion will have 18 electrons.

      Why the other options are wrong
      • A. A is incorrect since neon has 10 electrons where a sulphur Ion has 18.
      • C. C is incorrect since Helium has two electrons and sulphur ion has 18.
      • D. D is incorrect since krypton has 36 electrons where as sulphur Ion will have 18 electrons.

      Q132. The smaller the distance of the object from the eye, the visual angle will be:

      • A. Smaller
      • B. Greater
      • C. Constant
      • D. Negligible
      • E. None of the above

      Explanation: The visual angle of an object is determined by the size of the object's image on the retina. This angle increases as the object comes closer to the observer because the image projected on the retina becomes larger. Therefore, when the distance of the object from the eye decreases, the visual angle becomes greater. Option B is correct because it accurately describes this relationship. Other options fail to capture this dynamic change in visual angle with distance.

      Why the other options are wrong
      • A. Incorrect. When an object is closer to the eye, the visual angle increases, not decreases.
      • C. Incorrect. The visual angle is not constant; it changes depending on the distance of the object from the eye.
      • D. Incorrect. The visual angle is not negligible when the object is closer, as it actually increases.
      • E. Incorrect. The correct answer is that the visual angle becomes greater as the object moves closer to the eye.

      Q133. The efficiency of the Carnot's Engine working between 150°C and 50°C is:

      • A. 22.3%
      • B. 20.0%
      • C. 23.6%
      • D. 30.6%
      • E. 33.6%

      Explanation: The efficiency of a Carnot engine is calculated using the formula η% = (1 - T2/T1) × 100%, where T1 is the temperature of the hot reservoir and T2 is the temperature of the cold reservoir in Kelvin.Convert the given temperatures from Celsius to Kelvin: T1 = 150°C + 273 = 423 K and T2 = 50°C + 273 = 323 K.Substituting these values into the formula, η% = (1 - 323/423) × 100% = 23.6%.Options A, B, D, and E either apply the formula incorrectly or suggest efficiencies that are not supported by the calculated values.

      Why the other options are wrong
      • A. Wrong answer. The efficiency calculation was incorrect due to an error in the formula application.
      • B. Wrong answer. The temperatures were converted correctly, but the formula was applied incorrectly.
      • D. Wrong answer. This efficiency percentage exceeds the calculated value, indicating an error in the calculation process.
      • E. Wrong answer. This percentage is higher than the maximum theoretical efficiency calculated from the given temperatures.

      Q134. The principle of a capacitor is based on which of the following facts?

      • A. The potential of a conductor increases when the charge on it decreases, but this affects the charge stored in it.
      • B. The potential of a conductor is greatly reduced when the charge on it increases.
      • C. The potential of a conductor increases without affecting the charge stored in it.
      • D. The potential of a conductor is greatly reduced without affecting the charge stored in it.
      • E. The potential of a conductor increases as the charge on it increases.

      Explanation: The correct answer is that the potential of a conductor is greatly reduced without affecting the charge in it. This is the fundamental principle behind capacitors, which are used to store electric charge by reducing the electric potential of a conductor while maintaining its charge. This is achieved by introducing another conductor, either earth-connected or oppositely charged, in proximity to the first. Other options are incorrect because they either involve increasing potential or affecting the charge, which do not describe how capacitors function.

      Why the other options are wrong
      • A. This option is incorrect because an increase in potential with a decrease in charge does not align with the function of a capacitor, which aims to reduce potential without affecting the stored charge.
      • B. This option is incorrect because the potential of a conductor decreases without a change in the charge, which is achieved by the presence of another conductor.
      • C. This is incorrect as the primary principle of a capacitor involves reducing potential, not increasing it, while maintaining the charge.
      • E. This is incorrect as an increase in potential with an increase in charge does not align with how capacitors operate to store charge effectively.

      Q135. If in a circuit, 2 Ampere current is drawn from the battery in 10 minutes. How much charge will flow through the circuit in this time?

      • A. 1200 Coulombs
      • B. 600 Coulombs
      • C. 500 Coulombs
      • D. 20 Coulombs

      Explanation: DATA: Current I = 2 amp Time T = 10 minutes = 600 secCharge Q = ??SOLUTION : I= Q/TQ = ITQ = 600×2 Q = 1200 coloumb ans

      Why the other options are wrong
      • B. DATA: Current I = 2 amp Time T = 10 minutes = 600 secCharge Q = ??SOLUTION : I= Q/TQ = ITQ = 600×2 Q = 1200 coloumb ans According to formula calculation 600 coulombs is not correct answer.
      • C. DATA: Current I = 2 amp Time T = 10 minutes = 600 secCharge Q = ??SOLUTION : I= Q/TQ = ITQ = 600×2 Q = 1200 coloumb ansAccording to formula calculation 500 coulombs is not correct answer.
      • D. DATA: Current I = 2 amp Time T = 10 minutes = 600 secCharge Q = ??SOLUTION : I= Q/TQ = ITQ = 600×2 Q = 1200 coloumb ans According to formula calculation 20 coulombs is not correct answer.

      Q136. A body having translatory motion possesses _ and _. In the same way a body having rotatory motion possesses _ and _.

      • A. None of them
      • B. Linear velocity... Linear momentum... Angular velocity... Angular momentum
      • C. Linear momentum... Angular momentum... Linear velocity... Angular velocity
      • D. Angular velocity... Angular momentum... Linear momentum... Linear velocity

      Explanation: The correct answer is: Linear velocity... Linear momentum... Angular velocity... Angular momentum.In translatory motion, all points of a body move uniformly in a single direction, involving linear properties such as linear velocity and linear momentum. This type of motion does not change the orientation of the object.In contrast, rotatory motion occurs when a body rotates around its own axis, involving angular properties like angular velocity and angular momentum. For example, the Earth's rotation about its axis is a type of rotatory motion.All options except B do not properly align the motion types with their respective properties, which is why they are incorrect.

      Why the other options are wrong
      • A. This option is incorrect as both translatory and rotatory motions have specific properties associated with them.
      • C. Incorrect. The properties are mismatched with the types of motion. Translatory motion should be associated with linear properties, and rotatory with angular properties.
      • D. Incorrect. Angular and linear properties are swapped for the types of motion they should be associated with.

      Q137. The SI unit for intensity of sound is:

      • A. Joule per second
      • B. Watt per metre square
      • C. Watt metre square
      • D. Joule per metre square
      • E. Joule metre

      Explanation: Intensity is the amount of sound power passing through a unit area, and is measured in watts per square meter (W/m²). The correct answer is Option B: Watt per metre square. Other options do not represent intensity: Option A, Joule per second, measures power; Option C, Watt metre square, is not a recognized unit; Option D, Joule per metre square, measures energy density; and Option E, Joule metre, is not a standard physical unit.

      Why the other options are wrong
      • A. Joule per second is the unit of power, which measures energy transfer over time, not intensity.
      • C. This combination is not a standard unit for any physical quantity.
      • D. Joule per metre square describes energy density, not sound intensity.
      • E. Joule metre is not a recognized unit for any conventional physical quantity.

      Q138. A 50 watt bulb is operated by 120 volts. What is the current through the bulb?

      • A. 0.416 A
      • B. 1.5 A
      • C. 2.5 A
      • D. 3.5 A
      • E. 5.5 A

      Explanation: P=IV(50)=(120)(I)50/120=II=0.416A

      Why the other options are wrong
      • B. This is incorrect. Using P = IV, solving for I gives I = 50 W / 120 V = 0.416 A, not 1.5 A.
      • C. This is incorrect. Solving for current using I = P/V gives 0.416 A, not 2.5 A.
      • D. This is incorrect. The correct calculation for I = 50 W / 120 V results in 0.416 A, not 3.5 A.
      • E. This is incorrect. The calculation using I = P/V results in 0.416 A, not 5.5 A.

      Q139. There is a current of 25 A in a long straight wire. What is the flux density at a point 3 cm from the wire?

      • A. 1.67 x 10-4 T
      • B. 3.67 x 10-4 T
      • C. 5.67 x 10-4 T
      • D. 7.67 x 10-4 T
      • E. 9.67 x 10-4 T

      Explanation: Given, a=3cm=9×10−2m, I=25AB=μoI/2πa=4π×10−7×25/2π×3×10−2=1.67 x 10-4 T

      Why the other options are wrong
      • B. This option results from incorrectly calculating the flux density. Double-check the values used in the formula.
      • C. This option is incorrect. Verify if you used the correct distance and constants in the formula.
      • D. This calculation is incorrect. Ensure that you are using the correct units for distance in the formula.
      • E. This option is incorrect. Recheck the formula and values to ensure accurate calculations.

      Q140. Beta particles are the particles emitted from the _ of an atom.

      • A. Inner atomic shells
      • B. Outer atomic shells
      • C. Innermost atomic shell
      • D. Nucleus

      Explanation: The beta particle, which may be either negatively charged (negatrons) or positively charged (positrons), originates from the nucleus of an atom. A beta particle is emitted from the nucleus of an atom during radioactive decay. The electron, however, occupies regions outside the nucleus of an atom.

      Why the other options are wrong
      • A. Inner atomic shells: Incorrect. These contain electrons, which are not emitted as beta particles. Beta particles originate from nuclear processes.
      • B. Outer atomic shells: Incorrect. Electrons in these shells are not related to beta decay. Beta particles emerge from the nucleus.
      • C. Innermost atomic shell: Incorrect. This refers to the K-shell electrons, not the nucleus where beta particles originate.

      Q141. Name the pulmonary disease in which alveolar surface area involved in gas exchange is drastically reduced due to damage in the alveolar walls.

      • A. Pneumonia
      • B. Asthma
      • C. Pleurisy
      • D. Emphysema

      Explanation: Note:The correct option is d) Emphysema.Explanation of each option:a)Pneumonia: Pneumonia is an inflammatory lung condition primarily caused by infection, not by damage to the alveolar walls. It typically results in the air sacs (alveoli) filling with fluid or pus due to infection, rather than damage to alveolar walls.b)cAsthma: Asthma is a chronic respiratory condition characterized by airway inflammation, bronchoconstriction, and excess mucus production. It does not primarily involve damage to the alveolar walls but rather affects the airways.c)Pleurisy: Pleurisy, or pleuritis, is inflammation of the pleura, the lining around the lungs. It does not directly involve damage to the alveolar walls or impact the alveolar surface area responsible for gas exchange.d)Emphysema: This is the correct answer. Emphysema is a pulmonary disease characterized by the gradual destruction of the alveolar walls. This damage reduces the surface area available for gas exchange, leading to impaired lung function, shortness of breath, and other respiratory symptoms. Smoking is a common cause of emphysema. The destruction of the alveolar walls leads to the enlargement of the air sacs and loss of elasticity in the lungs. As a result, the surface area available for gas exchange is drastically reduced, impairing the lung's ability to efficiently transfer oxygen to the bloodstream and remove carbon dioxide. Summary: The correct answer is "Emphysema." Emphysema is a pulmonary disease characterized by damage to the alveolar walls, which drastically reduces the alveolar surface area involved in gas exchange. The other options, pneumonia, asthma, and pleurisy, do not primarily involve damage to the alveolar walls and are distinct conditions with different characteristics.

      Why the other options are wrong
      • A. Pneumonia is an inflammatory lung condition primarily caused by infection, not by damage to the alveolar walls. It typically results in the air sacs (alveoli) filling with fluid or pus due to infection, rather than damage to alveolar walls.
      • B. Asthma: Asthma is a chronic respiratory condition characterized by airway inflammation, bronchoconstriction, and excess mucus production. It does not primarily involve damage to the alveolar walls but rather affects the airways.
      • C. Pleurisy: Pleurisy, or pleuritis, is inflammation of the pleura, the lining around the lungs. It does not directly involve damage to the alveolar walls or impact the alveolar surface area responsible for gas exchange.

      Q142. How many types of modulations are possible with sinusoidal carrier?

      • A. Only one
      • B. Two
      • C. Three
      • D. Four

      Explanation: The carrier signal is a sine wave at the carrier frequency. The sine wave has three characteristics that can be altered. The term that may be varied is the carrier voltage Ec, the carrier frequency FC, and the carrier phase angle θ. So three forms of modulations are possible.

      Why the other options are wrong
      • A. This is incorrect. Modulation can involve altering amplitude, frequency, or phase, not just one aspect.
      • B. This is incorrect. While it's possible to use just two types of modulation, the standard practice involves three types: amplitude, frequency, and phase modulation.
      • D. This is incorrect. There are three main types of analog modulation: amplitude, frequency, and phase. A fourth type is not standard for sinusoidal carriers.

      Q143. Which of the following is not a base unit in the SI system?

      • A. Ampere
      • B. Second
      • C. Meter per second
      • D. Candela

      Explanation: In summary, the correct answer is option c) Meter per second, as it is not a base unit in the SI system. The other options (a, b, and d) represent base units: ampere for electric current, second for time, and candela for luminous intensity.

      Why the other options are wrong
      • A. The ampere (symbol: A) is the SI base unit for measuring electric current. It is a fundamental unit in the SI system, establishing the magnitude of an electrical flow.
      • B. The second (symbol: s) serves as the SI base unit of time. Defined by atomic properties, it is a cornerstone in the precise measurement of time intervals.
      • D. The candela (symbol: cd) is the SI base unit of luminous intensity, quantifying the power emitted by a light source in a specific direction. It is pivotal in light measurement.

      Q144. In the Compton Scattering experiment the X-ray wavelength change Δλ is _. Here h is Planck constant, m rest mass of electron and θ is angle after scattering.

      • A. Δλ = h/m0c (1 + cosθ)
      • B. Δλ = h/m0c (1 + cos2θ)
      • C. Δλ = h/m0c (1 - cosθ)
      • D. Δλ = h/m0c2 (1 + cosθ)

      Explanation: The correct answer is Option C: Δλ = h/m0c (1 - cosθ). This formula represents the Compton scattering equation, where Δλ is the change in wavelength of the X-ray, h is Planck's constant, m is the rest mass of the electron, c is the speed of light, and θ is the scattering angle.Option A is incorrect because it incorrectly adds the cosine term instead of subtracting it. Option B is incorrect because it squares the cosine term, which is not part of the Compton formula. Option D is incorrect as it erroneously includes \( c^2 \) in the denominator, which does not belong in the equation.

      Why the other options are wrong
      • A. This formula incorrectly adds the cosine term, which does not match the Compton scattering equation.
      • B. This formula incorrectly squares the cosine term, which is not part of the correct Compton scattering equation.
      • D. This formula incorrectly uses \( c^2 \) in the denominator, which is not part of the correct Compton scattering equation.

      Q145. A car of mass 1200 kg initially at rest has been accelerated to a speed of 8 m/s in 16 meters. Average acceleration of the car is _ m/s2? And force is _ N?

      • A. 1.5 and 1500
      • B. 2.5 and 2400
      • C. 3.5 and 3500
      • D. 2 and 2400

      Explanation: To solve this problem, we start by determining the acceleration using the kinematic equation v² = u² + 2as, where:v is the final velocity (8 m/s),u is the initial velocity (0 m/s, since the car starts from rest),a is the acceleration, ands is the displacement (16 m).Substituting the known values into the equation:(8)² = (0)² + 2(a)(16)64 = 32aa = 2 m/s²Next, apply Newton's second law to find the force: F = ma.F = 1200 kg × 2 m/s² = 2400 NTherefore, the correct values are an acceleration of 2 m/s² and a force of 2400 N. The other options are incorrect because they do not satisfy both the acceleration and force calculations based on the given conditions.

      Why the other options are wrong
      • A. Incorrect. If you calculate the acceleration using the kinematic equation, 1.5 m/s² will not match the given conditions. Recalculating the force with this acceleration will also lead to an incorrect answer.
      • B. Partially correct. The force is correct at 2400 N, but the acceleration of 2.5 m/s² is incorrect. Recalculate the acceleration using the equation of motion to verify.
      • C. Incorrect. Both the acceleration and force values are incorrect. The acceleration does not match the conditions given, and therefore the force is also wrong.

      Q146. Projectile must be launched at which angle with the horizontal to attain maximum range?

      • A. 90 degrees
      • B. 45 degrees
      • C. 75 degrees
      • D. 105 degrees
      • E. 145 degrees

      Explanation: To achieve maximum range, a projectile should be launched at an angle of 45 degrees with the horizontal. This angle provides the ideal balance between vertical and horizontal components of velocity, maximizing the distance traveled horizontally. The formula R = (v^2 sin2θ)/g confirms that maximum range occurs when sin2θ equals 1, which happens at θ = 45 degrees. Other angles, such as 90 degrees, result in no horizontal range, while angles greater than or less than 45 degrees reduce the range due to an imbalance in velocity components.

      Why the other options are wrong
      • A. Incorrect. At 90 degrees, the projectile goes straight up and comes straight down, resulting in zero horizontal range. The formula R = (v2 sin2θ)/g shows that sin2θ is zero when θ = 90 degrees.
      • C. Incorrect. At 75 degrees, the projectile has a higher vertical component of velocity, leading to a higher peak but a shorter range than at 45 degrees. The maximum range is achieved at 45 degrees.
      • D. Incorrect. Angles greater than 90 degrees imply the projectile is launched back towards the launch point with a reduced range. The optimal angle for maximum range is 45 degrees.
      • E. Incorrect. This angle results in a negative horizontal component of velocity, reducing the range significantly. The maximum range is achieved at 45 degrees.

      Q147. A block with a mass of 0.1 kg is attached to a spring and placed on a horizontal frictionless table. The spring is stretched 20 cm when a force of 5 N is applied, the spring constant is:

      • A. 50 Nm-1
      • B. 25 Nm-1
      • C. 75 Nm-1
      • D. 100 Nm-1
      • E. 125 Nm-1

      Explanation: To find the spring constant k, use Hooke's Law: F = kx. Given that F = 5 N and the extension x = 0.2 m, the equation becomes:5 = k(0.2)Solving for k gives k = 5 / 0.2 = 25 Nm-1.Option B is correct because it accurately reflects this calculation.Options A, C, D, and E are incorrect because they do not match the calculated value of the spring constant. They either overestimate or underestimate the spring constant due to incorrect application of the formula.

      Why the other options are wrong
      • A. Incorrect. Check your calculations for the spring constant using Hooke's Law, F = kx.
      • C. Incorrect. Double-check the values for force and extension and apply Hooke's Law correctly.
      • D. Incorrect. You might be overestimating the spring constant. Re-evaluate using F = kx.
      • E. Incorrect. This value is too high; ensure the calculation is based on the correct application of Hooke's Law.

      Q148. Two blocks, X and Y, of masses m and 2m respectively, are accelerated along a smooth horizontal surface by a force F applied to block X, as shown in the diagram.What is the magnitude of the force exerted by block Y on block X during this acceleration?

      • A. 0
      • B. F/3
      • C. F/2
      • D. 2F/3
      • E. F

      Explanation: Both blocks will be accelerated when the block X is applied by a force of magnitude F. Since, the total mass will be m+2m which is 3m.So, the acceleration of the system will be given as F=ma or a=F/3m. So, from this we can find the force acting on the block Y. So, to calculate the force on the block Y we have that F(y) =2m*a or 2m*F/3m which on solving we will get the force on the block y as F(y)= 2F/3Magnitude of the force exerted by block Y on block X during this acceleration is = 2F/3

      Why the other options are wrong
      • A. This is not correct as per explanation and calculations
      • B. This is not correct as per explanation and calculations
      • C. This is not correct as per explanation and calculations
      • E. This is not correct as per explanation and calculations

      Q149. The amount of heat at constant volume is called as:

      • A. Internal energy
      • B. Enthalpy
      • C. Entropy
      • D. Temperature
      • E. Pressure

      Explanation: At constant volume, the heat of the reaction is equal to the change in the internal energy of the system. Meanwhile, the heat of reaction at constant PRESSURE is known as enthalpy

      Why the other options are wrong
      • B. Enthalpy is a thermodynamic quantity that represents the total heat content of a system at constant pressure. It is given by the sum of the internal energy and the product of pressure and volume.
      • C. Entropy is a measure of the disorder or randomness in a system. It relates to the number of possible arrangements of particles within a system. Entropy change occurs in a reversible process, and it is not specific to constant volume conditions.
      • D. Temperature is a measure of the average kinetic energy of the particles in a system. While temperature can affect the amount of heat transferred, it is not specifically related to constant volume conditions
      • E. Pressure is the force exerted by a gas per unit area. While pressure can affect the behavior of gases, it is not specifically related to the amount of heat transferred at constant volume.

      Q150. A body is hanging from a rigid support by an extensible string of length L. It is struck inelastically by an identical body of mass m with horizontal velocity v =√2gl , the tension in the string increases just after striking by:

      • A. mg
      • B. 3mg
      • C. 2mg
      • D. None of these

      Explanation: Initially, the tension in the string is T = mg, which equals the weight of the hanging body. When struck by an identical body inelastically, the system's mass becomes 2m. Conservation of momentum gives us:mv = 2m(v'), thus v' = v/2.Using the inelastic collision principles, the new tension T' is given by T' - 2mg = 2m(v')^2/L. By substituting v' = v/2 and v = √(2gL), we find T' = 3mg.Therefore, the tension increase is T' - T = 3mg - mg = 2mg.Option A is incorrect as it ignores the momentum change. Option B miscalculates the velocity and resultant tension. Option D is incorrect since the calculated increase in tension is indeed 2mg, making Option C the right choice.

      Why the other options are wrong
      • A. This option assumes no change in velocity and tension after the collision, which is incorrect due to the inelastic nature of the collision.
      • B. This suggests an incorrect calculation of the increased tension, not accounting for the correct post-collision velocity.
      • D. Incorrect: The correct increase in tension is 2mg as calculated through conservation laws and force analysis.

      Q151. Which statement describes the electric potential difference between two points in the electric field of charge Q?

      • A. The difference of electric field between the points per unit charge.
      • B. The ratio of the power dissipated between the points to the mass of charge
      • C. The work done in moving a test charge between points divided by the magnitude of the test charge.
      • D. The force required to move a unit positive charge between the points per unit charge.

      Explanation: This question is simply revising how the electric potential is defined as it is work done per unit charge in moving that charge from one place to the other in the electric field.All others are not the definitions of electric potential.

      Why the other options are wrong
      • A. The difference of electric field between the points per unit charge: This describes the electric force or electric field strength, not the potential difference. Electric field is force per unit charge, while electric potential difference is work per unit charge.
      • B. The ratio of the power dissipated between the points to the mass of charge: Power dissipation is related to energy loss or work done over time. While related to potential difference (through the concept of power = voltage x current), this option doesn't define it directly. Also, the mass of the charge is not directly part of the definition of electric potential difference.
      • D. The force required to move a unit positive charge between the points per unit charge: This essentially describes the electric field strength. Electric potential difference is related to the work done, not the force required. While force is involved in doing work, this option doesn't capture the energy aspect inherent in potential difference.

      Q152. An electron moving with velocity v has momentum 3 x 10 -26 Kg.m/s. The de Broglie wavelength associated with it is _. Value of h = 6.63 x 10-34 is.

      • A. 24.1 nm
      • B. 22.14 m
      • C. 22.1 nm
      • D. 22.1 mm

      Explanation: The de Broglie wavelength formula is λ = h/p, where h is Planck's constant and p is the momentum of the electron. Given the momentum p = 3 × 10-26 Kg.m/s and h = 6.63 × 10-34 J.s, substitute these values into the formula to find λ:λ = 6.63 × 10-34 / 3 × 10-26 = 22.1 nm.Option A is incorrect due to a calculation error. Option B is incorrect because it suggests a much larger and incorrect unit (meters). Option D is incorrect due to the wrong unit (millimeters). Thus, Option C is the correct answer with the correct units and calculation.

      Why the other options are wrong
      • A. This is incorrect. The calculation mistake is due to a miscalculation in the division step of the de Broglie formula.
      • B. This is incorrect. The units are wrong. The de Broglie wavelength for an electron with given momentum should be in nanometers.
      • D. This is incorrect. The unit is incorrect. The correct unit should be nanometers for the given scale of momentum.

      Q153. The vector product of two vectors A and B is _ vectors A and B.

      • A. Not equal to the product of magnitudes of
      • B. In the plane parallel to
      • C. Perpendicular to the plane containing
      • D. Less in magnitude than the product of magnitudes of

      Explanation: The vector product, or cross product, of two vectors A and B results in a vector perpendicular to the plane containing A and B. This is determined using the right-hand rule, which helps visualize the direction of the resulting vector. The magnitude of the cross product is |A × B| = |A||B|sin(θ), where θ is the angle between A and B. Option C correctly identifies the perpendicular nature of the resulting vector. Option A is incorrect because it misrepresents the nature of the cross product as a scalar. Option B is incorrect because it misinterprets the orientation as parallel rather than perpendicular. Option D is incorrect because it inaccurately describes the magnitude relationship without considering the sine component.

      Why the other options are wrong
      • A. This option is incorrect. The vector product, or cross product, results in a vector, not a scalar, and its magnitude is given by |A||B|sin(θ), not just the product of magnitudes.
      • B. This option is incorrect. The cross product results in a vector that is perpendicular to, not parallel to, the plane containing the original vectors.
      • D. This option is incorrect. The magnitude of the cross product is based on |A||B|sin(θ), and it can be less than, equal to, or greater than the simple product of magnitudes, depending on the angle between the vectors.

      Q154. A car starts from rest and moves with a constant acceleration. During the 5th second of its motion, it covers a distance of 36 meters. What is the acceleration of the car?

      • A. 12.5 m/s2
      • B. 8 m/s2
      • C. 15 m/s2
      • D. 16 m/s2
      • E. 14 m/s2
      • F. 2.88 m/s2

      Explanation: You will find the distance traveled in 5 and 4 seconds individually. After subtracting these two terms and equating it to 36 meters, all variables are fulfilled other than a which we can solve for.In the below equations, s is distance, a is acceleration, and t is time.In 4 seconds, the truck covers:s = 1/2 at2s = 1/2 (a) 42s = 1/2 (a) (16)s = 8 (a) metersIn 5 seconds, the truck coverss = 1/2 a t2s = 1/2 (a) 52s = 1/2 (a) 25s = 12.5 (a) metersThe distance covered in 5 seconds minus the distance covered in 4 seconds is the distance (36 meters) covered in the 5th second.36 = 12.5 a - 8 a36 meters = 4.5 seconds2 (a)a = acceleration = 8 m/s2

      Why the other options are wrong
      • A. This value is incorrect. It results from incorrect calculations or assumptions about the time and distance relationship under constant acceleration.
      • C. This value is too high, which means the calculated acceleration is overestimated. Check the calculations for any arithmetic mistakes.
      • D. This value is double the correct answer, indicating a misunderstanding of the motion equations or a calculation error.
      • E. This is an overestimate. The calculations need to be revisited to ensure the correct use of formulas.
      • F. This value is too low, suggesting an error in applying the kinematic equations or misinterpretation of the data.

      Q155. The sinusoidal wave form can be varied by using which of the following parameters?I. Frequency of the carrier wave II. Amplitude of the carrier wave IIl. Phase angle

      • A. I only
      • B. I and II only
      • C. I and III only
      • D. III only
      • E. I, II and III

      Explanation: To modulate a sinusoidal wave, you can vary its amplitude, frequency, or phase angle. These parameters affect different characteristics of the wave:Amplitude: Changes the wave's intensity or loudness.Frequency: Alters the pitch or tone of the wave.Phase Angle: Shifts the wave's position in time, introducing phase shifts or time delays.Thus, all three parameters can be used to modulate a sinusoidal wave, making option E the correct choice. Other options are incorrect because they exclude one or more of these critical parameters.

      Why the other options are wrong
      • A. A. I only (Frequency of the carrier wave):The frequency determines how many cycles occur in a given time frame. Changing the frequency affects the pitch of the wave but doesn't impact other characteristics such as amplitude or phase.
      • B. B. I and II only (Frequency and amplitude of the carrier wave):Both frequency and amplitude are key parameters. Frequency changes the pitch, while amplitude affects the wave's intensity or loudness. However, this option excludes phase angle, which is also a modifiable parameter.
      • C. C. I and III only (Frequency of the carrier wave and phase angle):Frequency changes the wave's pitch, and phase angle shifts its position in time. However, this option does not consider amplitude, which is another crucial parameter in modulation.
      • D. D. III only (Phase angle):The phase angle only shifts the wave's position in time without affecting its frequency or amplitude. This is insufficient for fully characterizing sinusoidal wave variations.

      Q156. The speed of light is very nearly equal to;

      • A. 5x108 m/sec
      • B. 3x1016 m/sec
      • C. 4x108 m/sec
      • D. 3x108 m/sec
      • E. 7x108 m/sec

      Explanation: The speed of light in a vacuum is a fundamental constant of physics, known to be approximately 3x108 meters per second. This value is critical for many areas of physics and technology, including the theory of relativity. Option D correctly represents this speed. The other options are either too high or too low, and do not match the universally accepted value.

      Why the other options are wrong
      • A. This value is higher than the actual speed of light. The correct speed is approximately 3x108 m/s.
      • B. This value is extremely high and not consistent with the known speed of light, which is 3x108 m/s.
      • C. This value is slightly higher than the actual speed of light. The correct speed is 3x108 m/s.
      • E. This value is much higher than the actual speed of light. The correct speed is 3x108 m/s.

      Q157. The dimensions of acceleration are:

      • A. LT-1
      • B. LT-2
      • C. L3
      • D. L2
      • E. LT2

      Explanation: To find the dimensions of acceleration, start by understanding that acceleration is the change in velocity over time.Velocity is defined as distance over time, which has dimensions of [L][T-1].Thus, acceleration, being velocity per time, is [L][T-1]/[T] = [L][T-2].Option A ([LT-1]) is the dimension of velocity, not acceleration. Option C ([L3]) corresponds to volume, Option D ([L2]) to area, and Option E ([LT2]) is a miscalculation of time's exponent. Only Option B accurately reflects the dimensions of acceleration: [LT-2].

      Why the other options are wrong
      • A. This represents the dimensions of velocity, not acceleration.
      • C. This implies a volumetric dimension, which is unrelated to acceleration.
      • D. This suggests an area dimension, which is incorrect for acceleration.
      • E. This dimension suggests an incorrect relationship between length and time.

      Q158. R1 and R2 are two-position vectors making angles θ1 and θ2 with positive X-axis respectively. Their vector product is:[R1 = 4 cm, R2 = 3 cm , θ1 = 30 degrees , θ2 = 90 ]

      • A. 12√3
      • B. 6√3
      • C. 6√12
      • D. 12√6
      • E. 3√6

      Explanation: The vector product of two vectors, R1 and R2, is given by the formula |R1 × R2| = |R1| |R2| sin(θ2 - θ1), where θ is the angle between the vectors. Here, |R1| = 4 cm, |R2| = 3 cm, θ1 = 30°, and θ2 = 90°. Thus, |R1 × R2| = 4 × 3 × sin(90° - 30°) = 4 × 3 × 1/2√3 = 6√3 cm.This calculation confirms that the correct answer is 6√3 cm, directed along the Z-axis.The incorrect options result from errors in either the trigonometric calculations or angle substitutions, leading to incorrect values.

      Why the other options are wrong
      • A. This option is incorrect. It results from a miscalculation of the sine component or swapping of angles.
      • C. This option is incorrect due to an error in simplifying the trigonometric component or incorrect angle substitution.
      • D. This option is incorrect. It likely stems from an incorrect use of the trigonometric function or angle values.
      • E. This option is incorrect and results from either a calculation error in the sine component or incorrect angle usage.

      Q159. Coal and petrol are stores of chemical energy when are burnt, chemical energy is converted into heat energy i.e chemical energy = heat energy + _:

      • A. Electrical energy
      • B. Losses
      • C. Gains
      • D. Wind energy
      • E. Nothing

      Explanation: When coal or petrol is burned, the chemical energy stored in the fuel is primarily converted into heat energy. However, not all of this energy conversion is perfectly efficient; some energy is inevitably lost to the surroundings as waste heat, which is why 'Losses' is the correct answer. Electrical energy is not directly produced from combustion without additional equipment. Gains are incorrect because energy is not gained but redistributed with losses. Wind energy is unrelated to burning fuels. 'Nothing' is incorrect because energy transformations usually accompany some degree of energy loss.

      Why the other options are wrong
      • A. Electrical energy is not a direct result of burning coal or petrol; it requires a generator or similar device to be produced.
      • C. The energy conversion process in burning coal or petrol does not lead to a net energy gain but rather a redistribution of energy forms with some losses.
      • D. Wind energy is derived from atmospheric conditions and not from burning fuels like coal or petrol.
      • E. This option is incorrect because energy transformations typically involve some loss, often as waste heat.

      Q160. A 60 kg boy runs up a hill through a height of 6 m in 3 seconds. How much work does he do against gravitational force?

      • A. 3000 J
      • B. 2528 J
      • C. 3500 J
      • D. 3528 J

      Explanation: W=mgh=(60)(6)(9.8)=3528J

      Why the other options are wrong
      • A. This option mistakenly uses an incorrect value for gravity or miscalculates the product.
      • B. This option results from a calculation error, either in mass, height, or gravity.
      • C. This answer is slightly off due to rounding errors in calculation.

      Q161. The velocity of a particle is related to time according to the equationV= ct3. The dimensions of constant are _.

      • A. L-1 T-1
      • B. L T-3
      • C. LT -4
      • D. L-2 T-2

      Explanation: For the principle of homogeneity; V=ct3 (LT-1)=c(T3) c=LT-1/T3 c=LT -1-3 c=LT -4.

      Q162. The sum of kinetic energy and the potential energy is always constant provided that _ .

      • A. There is a greater force of friction involved during motion
      • B. The body is in simple harmonic motion
      • C. There is less force of friction involved during motion
      • D. No force of friction involved during motion

      Explanation: The law of conservation of energy states that energy can neither be created nor destroyed. According to this, the correct option is B because the total energy in simple harmonic motion will always be constant consisting of kinetic and potential energies. However, kinetic energy and potential energy are interchangeable. Given below is the graph of kinetic and potential energy vs instantaneous displacement.The graph for a body is SHM. Option D although seems to be correct, is incorrect because the type of motion is not specified and hence a particular motion can also include energies other than kinetic and potential which are not interchangeable.

      Q163. The formula for the Paschen series for the Hydrogen spectrum is _.

      • A. 1/λ=Rh(1/22 - 1/n2); n=3,4,5
      • B. 1/λ=Rh(1/42 - 1/n2); n=2,3,4,5
      • C. 1/λ=Rh(1/42 - 1/n2); n=5,6,7
      • D. 1/λ=Rh(1/32 - 1/n2); n=4,5,6

      Explanation: The correct formula for the Paschen series is Option D: 1/λ=Rh(1/32 - 1/n2); n=4,5,6. The Paschen series refers to electron transitions ending at the n=3 energy level, resulting in spectral lines in the infrared region. The other options represent different series or incorrect configurations: Option A represents the Balmer series, transitioning to n=2. Option B does not correspond to any recognised series due to its incorrect configuration. Option C represents the Brackett series, transitioning to n=4.

      Why the other options are wrong
      • A. This formula does not represent the Paschen series. It represents the Balmer series, which involves transitions to the n=2 level. The range of n values (3, 4, 5) does not apply to the Paschen series.
      • B. This formula does not represent the Paschen series. It is incorrect because it mistakenly uses n=4 as the lower energy level, which is not characteristic of any well-known series in the hydrogen spectrum.
      • C. This formula is incorrect for the Paschen series. It implies transitions ending at n=4, which corresponds to the Brackett series, not the Paschen series.

      Q164. A travelling wave, in which the particles of the distributed medium, move parallel to the direction of propagation of the wave is called:

      • A. Transverse wave
      • B. Circular wave
      • C. Longitudinal wave
      • D. Stationary wave

      Explanation: Longitudinal waves are characterized by particle motion that is parallel to the direction of wave propagation. This creates alternating regions of compression and rarefaction. Sound waves in air are a classic example, where air particles oscillate back and forth in the same direction as the wave is moving.Transverse waves, on the other hand, involve particle movement perpendicular to wave direction, as seen in waves on strings or electromagnetic waves. Circular waves are typically seen on water surfaces, where the motion is vertical and not parallel. Stationary waves involve a pattern of nodes and antinodes due to interference, with particles oscillating in place.

      Why the other options are wrong
      • A. A transverse wave involves particle movement perpendicular to the direction of wave propagation. Examples include waves on a string or electromagnetic waves.
      • B. Circular waves are typically observed on water surfaces, where the wave fronts expand in circles and particle motion is vertical, not parallel to the wave propagation direction.
      • D. Stationary waves, or standing waves, result from the interference of two waves traveling in opposite directions. The particles of the medium oscillate in place rather than traveling with the wave.

      Q165. A body starts sliding on a rough horizontal surface with a speed of 10 m/s. If the coefficient of friction is 0.2, find the distance traveled by the body before coming to rest. (g = 10m/s)

      • A. 15 m
      • B. 25 m
      • C. 35 m
      • D. 40 m
      • E. 55 m

      Explanation: Given that: v = 10 and u = 0.2 and g = 10 Solution = Using F = μN then, = μmg (here N = mg) So from above (ma = μmg); we got a = μg Now a = 0.2×10 = 2 m/s2Now using equation of motion V2=u2+2as 0 = 10×10 +2×2×s In solving it, we got s = 100/4 = 25 m Hence we get the correct answer.

      Why the other options are wrong
      • A. This is not correct as per explanations and calculations
      • C. This is not correct as per explanations and calculations
      • D. This is not correct as per explanations and calculations
      • E. This is not correct as per explanations and calculations

      Q166. A coil of 600 turns is threaded by a flux of 8x10-5 webers if this flux is reduced to 3x10-5 webers in 0.015 seconds. The average induced e.m.f. is:

      • A. -2.0 volts
      • B. -3.0 volts
      • C. +2.0 volts
      • D. +2.5 volts
      • E. +3.0 volts

      Explanation: Emf = - N (dФ/dt)where number of turns are denoted by N, dФ is the change in flux and dt is the time interval.Change in flux = Final Flux - Initial FluxChange in flux = (3 × 10⁻⁵) - (8 × 10⁻⁵) WbChange in flux = - (5 × 10⁻⁵) Wbtime interval = 0.015 sectime interval = 15 × 10⁻³ secNumber of turns in coil = 600Putting all the values in formula.Emf = - 600 × (-(5 × 10⁻⁵)/15 × 10⁻³) VoltsEmf = 600 × (5 × 10⁻²/15 ) VoltsEmf = 600 × (10⁻²/3 ) VoltsEmf = 200 × 10⁻² VoltsEmf = 2 Volts

      Why the other options are wrong
      • A. As per explanation, this is incorrect.Emf = - N (dФ/dt)where number of turns are denoted by N, dФ is the change in flux and dt is the time interval.Change in flux = Final Flux - Initial FluxChange in flux = (3 × 10⁻⁵) - (8 × 10⁻⁵) WbChange in flux = - (5 × 10⁻⁵) Wbtime interval = 0.015 sectime interval = 15 × 10⁻³ secNumber of turns in coil = 600Putting all the values in formula.Emf = - 600 × (-(5 × 10⁻⁵)/15 × 10⁻³) VoltsEmf = 600 × (5 × 10⁻²/15 ) VoltsEmf = 600 × (10⁻²/3 ) VoltsEmf = 200 × 10⁻² VoltsEmf = 2 Volts
      • B. As per explanation, this is incorrect.Emf = - N (dФ/dt)where number of turns are denoted by N, dФ is the change in flux and dt is the time interval.Change in flux = Final Flux - Initial FluxChange in flux = (3 × 10⁻⁵) - (8 × 10⁻⁵) WbChange in flux = - (5 × 10⁻⁵) Wbtime interval = 0.015 sectime interval = 15 × 10⁻³ secNumber of turns in coil = 600Putting all the values in formula.Emf = - 600 × (-(5 × 10⁻⁵)/15 × 10⁻³) VoltsEmf = 600 × (5 × 10⁻²/15 ) VoltsEmf = 600 × (10⁻²/3 ) VoltsEmf = 200 × 10⁻² VoltsEmf = 2 Volts
      • D. Emf = - N (dФ/dt)where number of turns are denoted by N, dФ is the change in flux and dt is the time interval.Change in flux = Final Flux - Initial FluxChange in flux = (3 × 10⁻⁵) - (8 × 10⁻⁵) WbChange in flux = - (5 × 10⁻⁵) Wbtime interval = 0.015 sectime interval = 15 × 10⁻³ secNumber of turns in coil = 600Putting all the values in formula.Emf = - 600 × (-(5 × 10⁻⁵)/15 × 10⁻³) VoltsEmf = 600 × (5 × 10⁻²/15 ) VoltsEmf = 600 × (10⁻²/3 ) VoltsEmf = 200 × 10⁻² VoltsEmf = 2 Volts
      • E. As per explanation, this is incorrect.Emf = - N (dФ/dt)where number of turns are denoted by N, dФ is the change in flux and dt is the time interval.Change in flux = Final Flux - Initial FluxChange in flux = (3 × 10⁻⁵) - (8 × 10⁻⁵) WbChange in flux = - (5 × 10⁻⁵) Wbtime interval = 0.015 sectime interval = 15 × 10⁻³ secNumber of turns in coil = 600Putting all the values in formula.Emf = - 600 × (-(5 × 10⁻⁵)/15 × 10⁻³) VoltsEmf = 600 × (5 × 10⁻²/15 ) VoltsEmf = 600 × (10⁻²/3 ) VoltsEmf = 200 × 10⁻² VoltsEmf = 2 Volts

      Q167. A rotating wheel of radius 0.5 m has an angular velocity of 5 rad/s at some instant and 10 rad / s after 5 s. Find the angular acceleration of a point on its rim.

      • A. 1 rad/s2
      • B. 3 rad/s2
      • C. 5 rad/s2
      • D. 7 rad/s2
      • E. 9 rad/s2

      Explanation: The angular acceleration of a rotating object can be found using the formula α = (ωf - ωi) / t, where ωf is the final angular velocity, ωi is the initial angular velocity, and t is the time interval. In this case, the initial angular velocity (ωi) is 5 rad/s, the final angular velocity (ωf) is 10 rad/s, and the time interval (t) is 5 seconds. Substituting these values into the formula gives: α = (10 rad/s - 5 rad/s) / 5 s = 1 rad/s2. Therefore, Option A is correct. All other options are incorrect as they do not result from applying this formula to the given values.

      Why the other options are wrong
      • B. It is incorrect as per the given formula.Option A is correct as ωf=ωi+αt.α= (ωf- ωi)/t= (10-5)/5=1rad/s2.Hence all other options are rendered as incorrect.
      • C. It is incorrect as per the given formula. Option A is correct as ωf=ωi+αt.α= (ωf- ωi)/t= (10-5)/5=1rad/s2.Hence all other options are rendered as incorrect.
      • D. It is incorrect as per the given formula. Option A is correct as ωf=ωi+αt.α= (ωf- ωi)/t= (10-5)/5=1rad/s2.Hence all other options are rendered as incorrect.
      • E. It is incorrect as per the given formula. Option A is correct as ωf=ωi+αt.α= (ωf- ωi)/t= (10-5)/5=1rad/s2.Hence all other options are rendered as incorrect.

      Q168. A shot leaves a gun at the rate of 160 m/s. Calculate the greatest distance to which it could be projected. (Take g = 10 m/s2).

      • A. 2460 m
      • B. 2560 m
      • C. 2680 m
      • D. 2760 m
      • E. 2860 m

      Explanation: For maximum distance(range) we assume that it is projected at 45 degrees. So, Rmax = u^2/g. (Following is the correct solution):

      Why the other options are wrong
      • A. Incorrect based on calculations. For maximum distance(range) we assume that it is projected at 45 degrees. So, Rmax = u^2/g
      • C. Incorrect based on calculations. For maximum distance(range) we assume that it is projected at 45 degrees. So, Rmax = u^2/g
      • D. Incorrect based on calculations. For maximum distance(range) we assume that it is projected at 45 degrees. So, Rmax = u^2/g
      • E. Incorrect based on calculations. For maximum distance(range) we assume that it is projected at 45 degrees. So, Rmax = u^2/g

      Q169. When the aircraft Concorde is moving in a horizontal plane at a constant speed of 650 ms-1, its turning circle has a radius of 80 km. What is the ratio of the centripetal force to the weight of the aircraft? (g = 9.8 m/s2)

      • A. 8.3 x 10^4
      • B. 0.54
      • C. 1.9
      • D. 52
      • E. 540

      Explanation: The ratio of Centripetal force to the weight of the aircraft=mv^2/r divided by mgm*(650)^2/80*1000 / m*9.81=0.54.

      Why the other options are wrong
      • A. Ratio of centripetal force to Weight of plane is MV2/R : MgV2/R : g = (650*650)/(80,000*9.8)=0.54= Answer.
      • C. Ratio of centripetal force to Weight of plane is MV2/R : MgV2/R : g = (650*650)/(80,000*9.8)=0.54= Answer.
      • D. Ratio of centripetal force to Weight of plane is MV2/R : MgV2/R : g = (650*650)/(80,000*9.8)=0.54= Answer.
      • E. Ratio of centripetal force to Weight of plane is MV2/R : MgV2/R : g = (650*650)/(80,000*9.8)=0.54= Answer.

      Q170. If the frequency of a pendulum is four times greater on an unknown planet than it is on Earth, then the gravitational constant on that planet is

      • A. 16 times greater
      • B. 4 times greater
      • C. 4 times lower
      • D. 16 times lower
      • E. 24 times lower

      Explanation: f=1 /2π√g/LIf the frequency is increased by a factor of 4 the impact on the value of g will be by a factor of 16.

      Why the other options are wrong
      • B. f=1 /2π√g/LIf the frequency is increased by a factor of 4 the impact on the value of g will be by a factor of 16.
      • C. f=1 /2π√g/LIf the frequency is increased by a factor of 4 the impact on the value of g will be by a factor of 16.
      • D. f=1 /2π√g/LIf the frequency is increased by a factor of 4 the impact on the value of g will be by a factor of 16.
      • E. f=1 /2π√g/LIf the frequency is increased by a factor of 4 the impact on the value of g will be by a factor of 16.

      Q171. A 40 kg block is resting at a height of 5m off the ground. If the block is released and falls to the ground. What is its total energy at a height of 2m? (g= 10 m/s2).

      • A. 0 J
      • B. 400 J
      • C. 2 kJ
      • D. 6 kJ
      • E. It cannot be determined from the information given.

      Explanation: The total energy the body possesses is the same at all times: We can calculate the energy of the body when it is 5m off the ground and that’ll be energy when is 2m above the ground too (though in KE form too) PE=mgh PE=(40)(10)(5)=2000J=2kJ

      Why the other options are wrong
      • A. Work done = P.E=mgh= 40kg x 10ms-2x 5m= 2kJ.Hence , all options except option C are incorrect.
      • B. Work done = P.E=mgh= 40kg x 10ms-2x 5m= 2kJ.Hence , all options except option C are incorrect.
      • D. Work done = P.E=mgh= 40kg x 10ms-2x 5m= 2kJ.Hence , all options except option C are incorrect.
      • E. Work done = P.E=mgh= 40kg x 10ms-2x 5m= 2kJ.Hence , all options except option C are incorrect.

      Q172. In an astronomical telescope, the distance between the objective and the eyepiece is called :

      • A. Magnifying Power of the telescope
      • B. Width of the telescope
      • C. Length of the telescope
      • D. Height of the telescope
      • E. Diameter of the lens of the telescope

      Explanation: The distance between the eyepiece lens and the objective lens is called the length of the telescope as shown below :

      Why the other options are wrong
      • A. The tube length g is the distance between the secondary focal point of the objective and the primary focal point of the eyepiece. The intermediate image serves as the object for the eyepiece.
      • B. The tube length g is the distance between the secondary focal point of the objective and the primary focal point of the eyepiece. The intermediate image serves as the object for the eyepiece.
      • D. The tube length g is the distance between the secondary focal point of the objective and the primary focal point of the eyepiece. The intermediate image serves as the object for the eyepiece.
      • E. The tube length g is the distance between the secondary focal point of the objective and the primary focal point of the eyepiece. The intermediate image serves as the object for the eyepiece.

      Q173. Look at this series: 12, 11, 13, 12, 14, 13, … What number should come next?

      • A. 10
      • B. 12
      • C. 13
      • D. 15

      Explanation: The sequence alternates between subtracting 1 and adding 2:Start with 12Subtract 1 to get 11Add 2 to get 13Subtract 1 to get 12Add 2 to get 14Subtract 1 to get 13Add 2 to get 15The next number is 15, following the established pattern of alternating operations. The incorrect options fail to maintain this pattern, either by miscalculating the operations or by failing to consider the alternation entirely.

      Why the other options are wrong
      • A. This choice assumes a faulty pattern that would subtract more than necessary and does not follow the sequence's established pattern of alternation.
      • B. This choice mistakenly assumes a repetition of the same number without considering the alternation of operations in the pattern.
      • C. This choice fails to recognize the increment by 2 in the sequence and only considers the subtraction step, breaking the pattern.

      Q174. Statements:I. There is an unprecedented increase in the number of young unemployed in comparison to the previous year.II. A large number of candidates submitted applications against an advertisement for the post of manager issued by a bank.

      • A. Statement I is the cause and statement II is its effect
      • B. Statement II is the cause and Statement I is its effect
      • C. Both statements I and II are independent causes
      • D. Both statements I and II are effects of independent causes

      Explanation: An increase in the number of unemployed youth is bound to draw in huge crowds for a single vacancy.

      Why the other options are wrong
      • B. This option is incorrect because it suggests that the increase in the number of young unemployed individuals (Statement I) is the cause, and the large number of job applications for the bank manager position (Statement II) is the effect. However, there is no logical or causal relationship between the two statements. They describe separate situations without any indication that one is causing the other.
      • C. This option is incorrect because it suggests that both the increase in the number of young unemployed individuals (Statement I) and the large number of job applications for the bank manager position (Statement II) are independent causes of something else. However, there is no context or information provided in the given statements to infer any relationship between these two scenarios or any external effect they might cause.
      • D. Both statements I and II are not the effects of independent causes because each statement describes different situations with their separate underlying factors or causes.

      Q175. What should come next to this word, "Recipe"

      • A. Desserts
      • B. Spoon
      • C. Utensils
      • D. Cookbook

      Explanation: A recipe is a list of directions to make something. Recipes may be used to prepare desserts, among other things. Utensils may or may not be used to make a recipe however a cookbook is needed to follow directions for a specific recipe.

      Why the other options are wrong
      • A. Recipes may be used to prepare desserts, among other things.
      • B. Spoon is used for mixing all the ingredients which are mentioned in the cookbook.
      • C. Utensils may or may not be used to make a recipe.

      Q176. A book cannot exist without?

      • A. Education
      • B. Pictures
      • C. Pages
      • D. Qualification

      Explanation: A book can still exist if it doesn’t have pictures; it can be a reading book without pictures; it might be a book to read for leisure and not for education; and it might not have any qualifications, but it will still be a book. However, without pages, a book cannot physically exist.

      Why the other options are wrong
      • A. If there is no education, books still exist. Hence, this option is incorrect.
      • B. If pictures do not exist, the book still may exist. Hence, this option is incorrect.
      • D. If there is no qualification, the books will remain unaffected and may still exist. Hence, this option is incorrect.

      Q177. Statement:I. Majority of the citizens in the locality belongs to higher income group.II. The sales in the local supermarket are comparatively much higher than in other localities.

      • A. Statement I is the cause and statement II is its effect.
      • B. Statement II is the cause and statement I is its effect
      • C. Both the statements I and II are independent causes
      • D. Both the statements I and II are effects of independent causes

      Explanation: The reason why sales are comparatively high in a particular locality is because the residents of the locality are capable of paying high prices. So option A is correct.

      Why the other options are wrong
      • B. Option B is incorrect because there is no indication that statement II (higher sales in the local supermarket) causes statement I (majority of citizens in the locality belonging to a higher income group).
      • C. Option C is incorrect because there is no evidence that both statements are independent causes. They may or may not have any causal relationship with each other.
      • D. Option D is incorrect because there is no information to suggest that both statements are effects of independent causes. Their relationship, if any, is not specified in the given information.

      Q178. Statement:I. Large number of Primary Schools in rural areas are run by only one teacher.II. There has been a huge dropout from primary schools in rural areas.

      • A. Statement I is the cause then 2 is its effect
      • B. Statement 2 is the cause then I is its effect
      • C. Both statements are independent causes
      • D. Both of the statements are effect of independent causes

      Explanation: One teacher running a lot of schools leads to mismanagement and it lowers the educational standard which causes students to drop out from school in rural areas. So, option A is the most accurate answer.

      Why the other options are wrong
      • B. Option B (Statement 2 is the cause, then I is its effect) is incorrect because the dropout from primary schools in rural areas can have various causes, and there is no indication that it directly causes the large number of schools run by one teacher.
      • C. Option C (Both statements are independent causes) is incorrect because the two statements do not appear to have any direct connection or correlation. They describe different situations without any clear causal relationship.
      • D. Option D (Both of the statements are effects of independent causes) is incorrect because there is no evidence provided to suggest that both statements are effects of distinct, unrelated causes. Again, they seem to describe different aspects of primary education in rural areas without any evident causal link.

      Q179. In an astronomical telescope, the lens called eyepiece forms an image of a distant object that is:

      • A. Real and diminished
      • B. Real and magnified
      • C. Virtual and diminished
      • D. Virtual and magnified

      Explanation: An astronomical telescope is an optical instrument which is used to see the magnified image of distant heavenly bodies. The final image formed by an astronomical telescope is always virtual, inverted and magnified.

      Why the other options are wrong
      • A. The eyepiece of an astronomical telescope does not form a real image. Its purpose is to magnify the image formed by the objective lens, and the final image is virtual.
      • B. While the image formed by the objective lens is real, the eyepiece forms a virtual image of this real image. The final image seen through the telescope is virtual and magnified.
      • C. The eyepiece does form a virtual image, but it is not diminished. The purpose of the telescope is to magnify the image, making it appear larger.

      Q180. Statements: 1. During the past year, Josh saw more movies than Stephen. 2. Stephen saw fewer movies than Darren. 3.Darren saw more movies than Josh. If the first two statements are true, the third statement is:

      • A. True
      • B. False
      • C. Uncertain
      • D. None of these

      Explanation: The statements tell us that Josh > Stephen and Darren > Stephen. However, there is no information to directly compare the number of movies seen by Josh and Darren. Darren could have seen more, fewer, or the same number of movies as Josh.

      Why the other options are wrong
      • A. This cannot be confirmed. Given the first two statements, Darren might have seen more movies than Josh, but it is not certain.
      • B. This cannot be confirmed. Given the first two statements, Darren might have seen more movies than Josh, but it is not certain.
      • D. This option is incorrect as Option C correctly identifies the uncertainty regarding whether Darren saw more movies than Josh.

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