Pk Mdcat Mock 2 — Solved Past Paper with Answers

Q1. Choose the correctly structured sentence:

• A. Had he lived in England he would miss his family.
• B. Had he lived in England he would have missed his family.✓
• C. Had he lived in England he had missed his family.
• D. Had he live in England he will missed his family.

Explanation: Option B is correct because it is the only sentence that adheres perfectly to grammar rules. The first part of the sentence is in the past perfect tense (indicated by the verb form "had he"), so the next part of the sentence should also conform to the same tense so the correct context should be “would have”.

Q2. Complete the sentences by choosing the most appropriate option, from the given lettered choices. Our football team has _ off the remarkable feat of winning the championship for three years in succession.

• A. brought✓
• B. brought of
• C. had brought
• D. have brought
• E. brought to

Explanation: The key to solving these questions is reading them in your head filling in each option and then deciphering which option fits in well. The correct preposition to use over here will be “brought” as the sentence is in the simple past tense.

Q3. The sentence which has one dependent and one independent clause is called a:

• A. Compound sentence
• B. Complex sentence✓
• C. Compound complex sentence
• D. Exclamatory sentence

Explanation: A sentence with one or more dependent clauses and at least one independent clause is a complex sentence. A sentence with two or more independent clauses plus one or more dependent clauses is called compound-complex or complex-compound. A compound sentence contains more than one subject and more than one predicate.

Q4. Identify the tense used in the given sentence: "You are always working on your laptop."

• A. Present indefinite tense
• B. Present perfect tense
• C. Present continuous tense✓
• D. Present perfect continuous tense

Explanation: Present continuous tense is formed through the subject + present form of the verb (‘working’) + present participle of the verb (‘are’). Here, the given sentence that is 'You are always working on your Laptop' is the present tense. As we know by the rule of grammar, the definition of the present tense is the activity that is done in the current state not in the past or the future. The person seems to be always working on his/her laptop. This is a declarative sentence. The verb 'are working' is in the present continuous tense. Hence, the correct answer is present continuous tense.

Q5. Read the Passage and Answer the Question: Poetry begins in trivial metaphors, petty metaphors, "grace" metaphors, and goes on to the profoundest thinking that we have. Poetry provides the one permissible way of saying one thing and meaning another. People say. "Why don't you say what you mean?" We never do that, do we? We like to talk in parables and in hints and in directions whether from diffidence or some other instinct. What selection best describes the word "diffidence" as used in the passage?

• A. Shyness✓
• B. Consternation
• C. Bewilderment
• D. Reservations
• E. Caution

Explanation: Diffidence over here means modesty or shyness resulting from a lack of self-confidence. Consternation is a feeling of anxiety or dismay, typically at something unexpected. Bewilderment means to be surprised. Reservations means to have some thoughts about something even before interacting with them. Caution means being careful.

Q6. A/An _ egg foetid the cake.

• A. Addled✓
• B. Fermented
• C. Rancid
• D. Acidulous

Explanation: -Addled means no longer edible. Sample sentence Due to exposure to sunlight, all of these bananas are addled. -Fermented means to undergo fermentation. Sample sentence: Milk becomes cheese by fermentation. -Rancid means having a foul smell due to chemical decomposition. Sample sentence: Curry goes rancid in heat. -Acidulous means acidic in nature. Sample sentence: He made acidulous remarks on her hard work because he was jealous of her promotion.

Q7. Identify errors in sentences:

• A. Neither the men who are listed as administrators nor the woman who is also listed has been appointed to the board.✓
• B. Neither the men who are listed as administrators nor the woman who is also listed have been appointed to the board.
• C. Neither the men who are listed as administrators nor the women who are also listed has been appointed to the board.
• D. Neither the men who is listed as administrators nor has the woman who is also listed been appointed to the board.

Explanation: When the subjects joined by or, nor, either ........ or, neither .........nor are of different persons, the verb agrees with the nearer.

Q8. Choose the correct sentence from the following

• A. The cheery trees stand over the woodland ride.
• B. The cheery trees stand about the woodland ride.✓
• C. The cheery trees beside about the woodland ride
• D. The cheery trees stand on the woodland ride.

Explanation: The correct option is B as it indicates that the cheery trees are next to the woodland ride

Q9. Identify the word or phrase that needs to be changed for the sentence to be correct: I go by the post office every morning on my way too work.

• A. I
• B. Post office
• C. On
• D. Too✓
• E. No error

Explanation: The verb “too” is wrongly used here.” Too” implies intensity or inclusiveness.The correct verb to use here will be “to”, which is a preposition.

Q10. Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. GLOOMY:

• A. Dark
• B. Bright✓
• C. Unexciting
• D. faint

Explanation: Gloomy means darkness so the best opposite to darkness will be “brightness”.

Q11. I love you. I can't _ the thought of ever losing you.

• A. Bear✓
• B. Bare
• C. Support
• D. Think of

Explanation: To 'bear the thought' means to endure something you are thinking.

Q12. Identify the word or phrase that needs to be changed for the sentence to be correct:

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

Explanation: The sentence sounds like it is in the past tense but the verb used here is in the present tense (send). It should be sent, instead.

Q13. Choose the correct sentence from the following:

• A. We should pay maximum accolade for our national heroes
• B. We should pay maximum accolade in our national heroes
• C. We should pay maximum accolade to our national heroes✓
• D. We should pay maximum accolade from our national heroes

Explanation: The preposition "to" is commonly used with the word "accolade." Therefore, the correct sentence is: "We should pay maximum accolade to our national heroes."

Q14. Which of the following is grammatically correct?

• A. In the end, they found there money over they're by the ATM.
• B. In the end, they found they're money over their by the ATM.
• C. In the end, they found their money over there by the ATM.✓
• D. In the end, they found there money over their by the ATM.

Explanation: In this sentence, we have two homophones—their and there. In this first instance, we need to show possession, so the correct form is their. In the second instance, we need an adverb representing a place, so the correct form is there.

Q15. Choose the CORRECT sentence from the following options:

• A. The best places to eat are casual, fun and you can get a meal for cheap.
• B. The best places to eat are casual, fun, can be termed with inexpensive.
• C. The best places to eat are casual, funny, and cheapest.
• D. The best places to eat are casual, fun, and inexpensive.✓

Explanation: When read aloud, A is correct, unlike B and C. Between A and D, D is correct because a comma appears before "and".

Q16. Identify the errors and choose the correct option: I hope this letters finds in the best of your spirits

• A. I hope this letter will find you in good of high spirits.
• B. I hope this letter finds you in the best of your spirit.✓
• C. I hope letter finds you in the best of spirits.
• D. I hope the letter found ingreatest of sprite.

Explanation: There are two grammatical errors in the sentence above. An object (pronoun/noun) should be used to correctly identify the entity to whom the letter is sent. Option A is incorrect since it makes use of the future tense – indicated by “will find” – while the person will be reading the letter in the present. Option C and Option D are incorrect since they lack the determiner “this” which is necessary to indicate that the letter being mentioned is specific in nature (i.e. the letter that is being read currently). By elimination, Option B is correct.

Q17. Complete the sentence by choosing the most appropriate option: Some people _ claim to be vegetarians actually allow themselves to eat fish and chicken.

• A. that
• B. which
• C. whom
• D. who✓

Explanation: People are nouns referring to person, the best pronoun to use in this case thus will be to use “who”.

Q18. Enzymes which are involved in transfer of electrons are known as?

• A. Oxidases
• B. Dehydrogenases
• C. Hydrolyses
• D. Both a and b✓

Explanation: Oxidases are enzymes that catalyze the transfer of electrons from a substrate to oxygen, while dehydrogenases are enzymes that catalyze the transfer of electrons from a substrate to an electron acceptor (such as NAD+ or FAD). Both of these types of enzymes are involved in the transfer of electrons, which is a key aspect of many metabolic pathways.

Q19. 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: Opion A: Vas deferens is a long, muscular tube that transports sperm cells from the testes to the ejaculatory duct. It is about 18 inches long and is located in the scrotum. Option B: Malpighian tubular system is a network of tubules that are found in the kidneys. They are responsible for filtering blood and removing waste products. They do not play a role in the production of gametes. Option C: Seminiferous tubule is a network of tiny tubes found within the testes. They are where sperm cells are produced through a process called spermatogenesis. The seminiferous tubules are lined with cells that divide and differentiate into sperm cells. Option D: Ejaculatory duct is a short, muscular tube that carries sperm cells from the vas deferens to the urethra. It is about 1.5 inches long and is located in the prostate gland. Option E: Testicular duct system is a network of tubules that transports sperm cells from the seminiferous tubules to the epididymis. It is also known as the rete testis.

Q20. Vocal cords, which help in voice production are two thin edged fibrous bands, present in:

• A. Glottis
• B. Bronchus
• C. Larynx✓
• D. Trachea
• E. Pleura

Explanation: The vocal cords are two thin, fibrous bands located in the larynx or voice box, which is a part of the respiratory system. The vocal cords vibrate when air passes through them, producing sound and allowing us to speak.

Q21. Three word equations are shown: P. Carbon dioxide + water gives glucose + oxygen Q. Glucose + oxygen gives carbon dioxide + water R. Glucose gives alcohol + carbon dioxide What is / are the equations for anaerobic respiration in yeast?

• A. P only
• B. Q only
• C. R only✓
• D. all of the above

Explanation: Anaerobic respiration in yeast has the following equation: C6H12O6 --> 2CO2 + 2C2H5OH + 2 ATP

Q22. If we add more substrate to an already occurring enzymatic reaction and it has no affect on the rate of reaction, the process is called?

• A. Denaturation
• B. Saturation✓
• C. Composition
• D. Inhibition

Explanation: If adding more substrate to an already occurring enzymatic reaction has no effect on the rate of the reaction, the process is called "enzyme saturation" or reaching the "maximum velocity" of the reaction. At low substrate concentrations, the reaction rate increases with increasing substrate concentration. However, once the enzyme is saturated (i.e., all active sites are occupied), adding more substrate does not increase the rate of the reaction, and the reaction has reached its maximum velocity.

Q23. Pseudopodia are:

• A. False feet developed in some unicellular organisms✓
• B. Small hairlike structures present on the unicellular organisms
• C. Long, tube like structures coming out of the mouth
• D. Suckers which are attached to the walls of intestines

Explanation: A pseudopod or pseudopodia is a temporary arm-like projection of a eukaryotic cell membrane that emerges in the direction of movement. The hair-like projections on unicellular organisms are called Cilia. The long tube-like structure connecting the mouth and the stomach is called the oesophagus. The head of some parasites contains structures, suckers which enable the parasite to attach to the gut wall. So option A is correct

Q24. The smaller (40S) of ribosome combines with larger subunit (60S) in the presence of Mg2+ ion to form _ particle.

• A. 100 S
• B. 90 S
• C. 80 S✓
• D. 70 S

Explanation: The S in the ribosomal subunits stands for svedberg units. It represents the different sedimentation rates of the ribosomes during centrifugation. The 60s and 40s ribosomal subunits join to form an 80S ribosome found in eukaryotes.

Q25. The following statements are about enzymes: 1. They are globular proteins except riboenzyme2. They can be inhibited 3. 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.

Q26. The type of bronchitis that causes no permanent damage to the lungs and lasts for two weeks is known as:

• A. Acute bronchitis✓
• B. Chronic bronchitis
• C. Coastal bronchitis
• D. Intercostal bronchitis

Explanation: 'Chronic bronchitis' is long-term inflammation of the bronchi. It is common among smokers. People with chronic bronchitis tend to get lung infections more easily.'Acute bronchitis' is a contagious viral infection that causes inflammation of the bronchial tubes - these are the airways that carry air into your lungs. When these tubes get infected, they swell and Mucus (thick fluid) forms inside them. This narrows the airways, making it harder for you to breathe.

Q27. Enzymes that are involved in the control and regulation of biological processes are?

• A. Allosteric enzymes
• B. Inhibitors
• C. Regulators✓
• D. None of these

Explanation: Option C is correct since enzymes are known as regulators when they are used for the maintenance of biological processes in living beings. Option A is incorrect since allosteric enzymes can play a role in both feedback inhibition and once combined with an irreversible non-competitive inhibitor, they can be permanently damaged. So, they are not always regulatory. Option B is incorrect since inhibitors decrease the rate of enzyme activity. Some of them do play a role in feedback inhibition, but not all of them do this. Option D is incorrect since it states none of these, which is not the case.

Q28. True breeding variety is produced by which of the following?

• A. Cross-fertilization
• B. Self-fertilization✓
• C. Both Options A and B are correct
• D. None of these options is correct

Explanation: Option A : Cross-fertilization involves the fertilization of one plant by the pollen from another plant. This can lead to the mixing of different alleles from the two parent plants, resulting in offspring that are genetically diverse and may not have the same traits as the parent plants. Therefore, cross-fertilization is not a reliable method for producing true breeding varieties. Option B: With plants, true-breeding occurs when plants produce only offspring of the same variety when they self-pollinate. For instance, a plant that has blue flowers will produce only seeds that will grow into plants that have blue flowers. With true breeding, the trait is passed on to all subsequent generations.

Q29. It uses the single strand RNA as a template for making double stranded DNA:

• A. DNA polymerase
• B. DNA ligase
• C. Reverse transcriptase✓
• D. All of these
• E. All

Q30. Inside ovary, primary oocyte divides through first meiotic division, forming two haploid cells, the secondary oocyte and:

• A. Ovum
• B. Oogonium
• C. Follicle cell
• D. Polar body✓

Explanation: Inside the ovary, during the process of oogenesis, the primary oocyte undergoes the first meiotic division, resulting in the formation of two haploid cells. These cells are the secondary oocyte and a smaller cell called the first polar body. The first polar body is a smaller cell that contains a portion of the genetic material but minimal cytoplasm. The polar bodies typically do not play a direct role in fertilization and are eventually broken down or reabsorbed.

Q31. The optimum pH for enzyme arginase is?

• A. 9
• B. 9.3
• C. 9.7✓
• D. 10

Explanation: The optimum pH of arginase is typically around 9.5-10.5. Arginase is an enzyme that catalyzes the hydrolysis of arginine to ornithine and urea. The optimum pH for arginase activity can vary depending on the specific type of arginase and the organism it comes from. Generally, arginase is active in a slightly alkaline pH range.In humans, for example, arginase I, which is primarily found in the liver, has an optimum pH around 9.5. On the other hand, arginase II, found in other tissues, may have a slightly different optimum pH.

Q32. Cooperation of the two photosystems of the chloroplast is required for_

• A. ATP synthesis
• B. Reduction of NADP✓
• C. Cyclic photophosphorylation
• D. Oxidation of the reaction center of photosystem I

Explanation: Non-cyclic photophosphorylation is the light-dependent part of photosynthesis in higher plants, in which an electron donor is required, and oxygen is produced as a waste product. It consists of two photo reactions cooperating, resulting in the reduction of NADP+ into NADPH 2 . So, the correct option is 'reduction of NADP+'.

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

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

Explanation: In the process of spermatogenesis, spermatogonium is the diploid cell that divides mitotically to produce two daughter cells - one remains as spermatogonium for further division, and the other differentiates into primary spermatocyte. In the given figure, A is marked as spermatogonium, indicating that it is a diploid cell that will divide mitotically to produce more spermatogonia. Therefore, option B is the correct answer.

Q34. Drosophila flies with XXY genotype are females, but human beings with such genotype are abnormal males. It shows that:

• A. The Y-chromosome is essential for the sex determination of Drosophila.
• B. Y-chromosome is female determining in Drosophila.
• C. Y-chromosome is male-determining in human beings.✓
• D. Y-chromosome has no role in sex determination either in Drosophila or human beings

Explanation: 'Genic Balance Theory' was proposed by C.B. Bridges in 1922 for sex determination in Drosophila. It states that the ratio of the number of X-chromosomes to that of a complete set of autosomes determines the sex of Drosophila. According to this theory of sex determination, if the ratio of the X chromosome to a total number of sets of autosomes (X/A) is > 1, the organism will be super female. If the ratio of the X chromosome to the total number of sets of autosomes (X/A) falls between 1 and 0.50, the genotype will show an intersex phenotype. The X/A value is 1.0 for normal females and 0.5 for normal males. It clearly shows that in Drosophila autosome bears genes that incline for maleness and X chromosome bears genes that incline for femaleness; the Y-chromosome does not play any role in sex determination in Drosophila. It makes options A and B wrong. The presence of Y-chromosome in humans determines the male sex and its absence results in the female sex. Human males carry XY and females carry XX sex chromosomes. Option D is wrong and C is correct. Thus, the correct answer is option C.

Q35. The mobility of integral proteins can be measured by physical state of which of the following?

• A. Amino acids
• B. External phospholipids
• C. Membrane phospholipids✓
• D. Membrane appendages

Explanation: Option C is correct since integral proteins are embedded in the 'phospholipid bilayer' of the membrane, the mobility of the integral proteins is determined largely by the physical state of membrane phospholipids.

Q36. Which of the following is NOT a difference that would allow one to distinguish between a prokaryotic and a eukaryotic cell? Presence of absence of the nucleus Presence or absence of the cell wall Membrane bound versus no membrane bound organelles

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

Explanation: Eukaryotic cells have nucleus and membrane-bound organelles, which is not the property of prokaryotes.The cell wall is not a distinguishing feature between prokaryotes or eukaryotes.

Q37. Human accumulated glycogen is an example of

• A. phospholipid
• B. polysaccharides
• C. carbohydrates
• D. both b and c✓

Explanation: Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body. Polysachharide is a type of carbohydrates.

Q38. ATP is used

• A. to synthesize the macromolecules
• B. to transport molecules and ions
• C. to perform mechanical work
• D. all of above✓

Explanation: ATP is the energy currency of the cell, meaning it can be broken down to release energy when needed by the body. All the functions mentioned require energy and thus ATP

Q39. Which is the correct order of energy transfer from accessory pigments to main photo synthetic pigment?

• A. Carotenoids, Chlorophyll a, Chlorophyll b
• B. Chlorophyll b, Carotenoids, Chlorophyll a
• C. Carotenoids, chlorophyll b, Chlorophyll a✓
• D. Chlorophyll a, Chlorophyll b, Carotenoids

Explanation: The correct order of energy transfer from accessory pigments to the main photosynthetic pigment is from carotenoids to chlorophyll b to chlorophyll a. Carotenoids absorb light energy and transfer it to Chlorophyll b, which, in turn, transfers the energy to Chlorophyll a, where the actual photosynthesis process takes place.

Q40. What are the functions of the inter, motor and sensory neurons in a reflex response?

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

Explanation: To relay nerve impulses from within the CNS, interneurons are used.To conduct the nerve impulses from the CNS to the effector, motor neurons are used. To conduct the nerve impulses from the receptors to the CNS, sensory neurons are used.

Q41. Which of the following statements are true about the capsomeres?

• A. It is an individual unit of the capsid✓
• B. It is a viral protein for replication
• C. It is a unit of nucleic acid in viruses
• D. All of the above

Explanation: Capsomeres are tiny subunits that make up the protein coat, referred to as the capsid. Capsomeres are known as capsid subunits, which are the outer protective covering of proteins that protect the virus' genetic material. It plays no role in the replication of the virus. So, option A is the best option.

Q42. All of these are inhibitors of enzymes except

• A. Antibiotics
• B. Anti metabolites
• C. Cyanide
• D. Succinic acid✓

Explanation: An enzyme inhibitor is a molecule that binds to an enzyme and decreases its activity, while succinic acid is a substrate.

Q43. Cyanobacteria help in nitrogen fixation because they have:

• A. Sodium channels
• B. Heterocysts✓
• C. Hormogonia
• D. Nitrogenase

Explanation: Cyanobacteria have specialized nitrogen-fixing cells called heterocysts which play a vital role in nitrogen fixation.

Q44. Acetyl CoA completely oxidizes to Carbon dioxide and liberates _.

• A. NADH and FADH
• B. NADP and FADP
• C. ATP
• D. ATP, NADH and FADH2✓

Explanation: When acetyl CoA undergoes complete oxidation in the citric acid cycle (also known as the Krebs cycle or tricarboxylic acid cycle), it liberates carbon dioxide and transfers high-energy electrons to carrier molecules. The overall chemical reaction for the complete oxidation of one molecule of acetyl CoA in the citric acid cycle is: Acetyl CoA+3NAD++FAD+GDP+Pi+2H2​O→2CO2​+3NADH+3H++FADH2​+GTP+CoA The NADH and FADH2 generated in this process carry high-energy electrons to the electron transport chain, where they contribute to the synthesis of ATP through oxidative phosphorylation. The carbon dioxide produced is a byproduct of the decarboxylation reactions that occur during the citric acid cycle.

Q45. The respiratory chain electron carrier that directly binds oxygen is:

• A. Cytochrome a
• B. Cytochrome a3✓
• C. Cytochrome c1
• D. Cytochrome b

Explanation: The respiratory chain electron carrier that directly binds oxygen is cytochrome a3. Cytochrome a3 is the final electron carrier in the electron transport chain, and it is located in complex IV. When electrons are transferred to cytochrome a3, they are oxidized and combine with oxygen to form water.

Q46. The division of cocci in three planes results in formation of a:

• A. Tetrad
• B. Sarcina✓
• C. Grape like clusters
• D. All of the above options are correct

Explanation: Option A; cells in a square arrangement, tetrads.Option B: The cocci are arranged in a cuboidal manner, as the cells are formed by regular cell divisions in three planes. Cocci that divide in three planes and remain in groups cube like groups of eightOption C: Staphylococcus aureus, which usually forms grape-like clusters, has the ability to form regularly arranged cell packets.

Q47. Which of the following is a copper containing protein in electron transport chain?

• A. Plastoquinone
• B. Cytochrome - C
• C. Plastocyanin✓
• D. Ferredoxin

Explanation: It serves as an electron transfer agent between the cytochrome complex which follows Photosystem II and the entry point to Photosystem I of the non-cyclic electron transfer process. The electron transport chain is a series of electron transporters embedded in the inner mitochondrial membrane that shuttles electrons from NADH and FADH2 to molecular oxygen. In the process, protons are pumped from the mitochondrial matrix to the intermembrane space, and oxygen is reduced to form water.

Q48. Steroids consist of _ 6 membered carbon rings and one 5 membered carbon ring.

• A. Four
• B. Three✓
• C. Two
• D. Five
• E. Six

Explanation: The steroid core structure is typically composed of seventeen carbon atoms, bonded in four "fused" rings: three six-member cyclohexane rings and one five-member cyclopentane ring.

Q49. Where is the double stranded DNA of the bacteriophage found?

• A. Tail
• B. Sheath
• C. Collar
• D. Head✓

Explanation: Option D is correct since the double-stranded DNA molecule is present within the head. The upper hexagonal-shaped part is the head. Moreover, these are the tad-pole-shaped viruses that attack bacteria and were first discovered by Twort.

Q50. During spermatogenesis, the _, which are haploid cells eventually mature into spermatozoa/mature sperms:

• A. Spermatogonia
• B. Primary spermatocytes
• C. Spermatids✓
• D. Secondary spermatocytes

Explanation: Option A, spermatogonia, are diploid cells and are the first stage in the process of spermatogenesis. They have not undergone meiotic division, and as such are diploid.Option B, primary spermatocytes, are also diploid cells, as they arise from mitotic divisions of the spermatogonia which themselves are diploid. They are not a product of meiosis.Option C, spermatids, is the correct answer. This is because they are the end product of Meiosis II and as such are haploid cells. Furthermore, they themselves are the direct precursors to mature spermatozoa as they further differentiate to form mature sperm cells.Option D, secondary spermatocytes, are also haploid cells and are the cells which give rise to spermatids. This is not the correct answer as the question is asking for a haploid cell that matures into spermatozoa/mature sperm cells. Secondary spermatocytes give rise to spermatids first which then go on to mature into spermatozoa so, spermatids fit the given scenario.

Q51. Genotype of blood group 'AB' in human is _.

• A. IA IB✓
• B. IB Io
• C. IA IA
• D. IoIo

Explanation: ABO blood type in humans is determined by 3 allelesIA, IB (Dominant) and i (Recessive)Genotype IA shows blood group A.Genotype TB shows blood group B.Genotype Io shows blood group O.But, IA & IB are co-dominant alleles means neither of the dominant alleles can mask the expression of other dominant alleles.So, the genotype IA IB shows blood group AB.

Q52. Breaking of the terminal phosphate of ATP releases about _ kcal/mol of energy.

• A. 6.1
• B. 6.3
• C. 7.1
• D. 7.3✓

Explanation: The release of terminal phosphate in a single ATP molecule occurs using water, the energy released is equivalent to 7.3Kcal/mol.

Q53. The number of functional parts in the forebrain are:

• A. 2
• B. 3✓
• C. 4
• D. 5

Explanation: The forebrain can be divided into three functional parts namely the thalamus, the limbic system and the cerebrum.1. Thalamus: it acts as the main relay station for your brain, all motor and sensory signals pass through this structure in the centre of the brain.2. Limbic system: This is the part of the brain involved in behavioural and emotional responses.3. Cerebrum: This is the largest part of the brain, it is divided into two hemispheres namely the cerebral hemispheres. Areas within the cerebrum control muscle function and speech along with thoughts, emotions reading, writing and learning.

Q54. Which of the following structures provides greater pathogenicity to the bacteria?

• A. Slime✓
• B. Cell Wall
• C. Cell Membrane
• D. Capsule

Explanation: In the question, you need to identify the structure that provides greater pathogenicity to the bacteria. While each component has some effect on bacterial pathogenicity, the slime, which is a soluble sheath of macromolecules, provides greater pathogenicity to bacteria while also protecting them from phagocytosis. Hence, Option A is the correct answer.

Q55. Which of the following is a compensation point?

• A. Leaves respire utilizes O2 and releases CO.
• B. Photosynthesis and respiration occur at the same rate. So there is no net exchange of gases between the atmosphere and plants.✓
• C. The rate of photosynthesis increases, and so does the O2 production, with a net release of oxygen coupled with the uptake of CO2
• D. The rate of respiration becomes more than the rate of photosynthesis.16 Net yield of H2O in Photosynthesis is

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

Q56. If the non-protien part is loosely attached to the protein part in the enzyme, it is known as _.

• A. Coenzyme✓
• B. Prosthetic group
• C. Cofactor
• D. Apoenzyme

Explanation: Prosthetic groups are compounds bound to enzymes by a covalent bond and their change from one form to another and back takes place in a single catalytic cycle. Coenzymes are organic molecules and quite often bind loosely to the active site of an enzyme. The term cofactors unite coenzymes and prosthetic groups. The meaning of apoenzyme is a protein that forms an active enzyme system by combination with a coenzyme.

Q57. Long bones function in

• A. support
• B. support, erythrocyte and leucocyte synthesis✓
• C. support and erythrocyte synthesis
• D. erythrocyte formation

Explanation: Long bones strengthen the legs and arms, provide support and also synthesise erythrocytes and leucocytes due to presence of bone marrow in their cavities.

Q58. The enzymes required for the Kreb cycle are found in _.

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

Explanation: The Krebs cycle enzymes are membrane proteins found within the matrix of the mitochondria except for succinate dehydrogenase which is an integral membrane protein locked to the inner mitochondrial membrane.F1 particle is found in the matrix of mitochondria and is found attached to the cristae. It plays a very important role in the production of ATP molecules as it contains an enzyme called ATPaseA lysosome is a membrane-bound cell organelle that contains digestive enzymes.The cytoplasm is a thick solution that fills each cell and is enclosed by the cell membrane.

Q59. A bacteria without flagella is called:

• A. Amphitrichous
• B. Atrichous✓
• C. Lophotrichous
• D. Peritrichous

Explanation: Based on their flagella, bacteria can be classified as follows: Atrichous have no flagella (the suffix 'a' usually implies an absence of something) Monotrichous have one flagellum at one end only ('mono'=one) Lophotrichous have a tuft of flagella at one end ('lopho' = tuft) Bitrichous have one flagellum on each end ('bi'= two) Peritrichous have flagella all over the surface (peri = around) Amphitrichous have a tuft of flagella at both ends

Q60. If we cross round yellow seeded plant with green wrinkled seeded plants, what will be phenotypic ratio at F2 generation?

• A. 9:3:3:1✓
• B. 9:4:3:2
• C. 3:9:3:1
• D. 8:3:3:2
• E. 9:1:3:3

Explanation: The answer is A since the question asks us to find the ratio of the F2 generation so we can assume the given plants are homozygous with one being homozygous dominant for both characteristics and the other being homozygous recessive. We infer their homozygosity from the fact that they are from the parental generation and the F1 generation, consequently would be heterozygous for both properties as well. For F2 generation, we can draw a Punnett square to find the ratio when the heterozygous plant of the F1 generation self-pollinates.

Q61. Genes that influence height in humans are:

• A. Codominant
• B. Epistatic
• C. Polygenes✓
• D. Pleiotropic

Explanation: Option A: Both alleles of a gene are expressed equally and independently in the 'Heterozygous' condition. Offspring shows the phenotype of both parents. Option B: One gene suppresses the expression of another gene that is located at a different locus. Option C: 'Polygenes' control continuously varying traits, which are controlled by alleles of two or more separate genes located at different loci. The genes are called polygenes. In humans, skin color, height, and intelligence are examples of polygenic traits. Option D: 'Pleiotropy' refers to multiple effects of a single gene.

Q62. The optimum pH of catalase is:

• A. Slightly alkaline✓
• B. Highly acidic
• C. Highly alkaline
• D. Slightly acidic

Explanation: The optimum pH of catalase is slightly alkaline, with a range of 6.8 to 7.2. This means that catalase works best at a pH that is slightly higher than neutral. Catalase is an enzyme that is found in most cells, and it is responsible for breaking down hydrogen peroxide. Hydrogen peroxide is a toxic substance, so catalase is important for preventing cell damage.

Q63. Which of the following is basic function of bacterial slime capsule?

• A. Protection from enviroment
• B. Protection from engulfment✓
• C. Protection from osmotic lysis
• D. All of the above

Explanation: Capsule is tightly bound to the bacterial cell. It is a part of the cell envelope. It protects cells from engulfment by Eukaryotic cells such as macrophages and it also protects the cells from pathogenicity. Hence option B is correct.Option A and C is incorrect because the cell wall of bacteria protects the cell against osmotic lysis and against environment.

Q64. Phosphofructokinase enzyme converts fructose-6-phosphate into _.

• A. Fructose-I ,4-phosphate
• B. Fructose-1,6-bisphosphate✓
• C. Bisphosphate
• D. Fructose

Explanation: The enzyme phosphofructokinase transforms fructose-6-phosphate to fructose-1,6-diphosphate.

Q65. Chlorophyll b is found in which organisms?

• A. Green plants
• B. Green algae
• C. Animals
• D. Both Options A and B are correct✓

Explanation: There are four types of chlorophyll: chlorophyll a, found in all higher plants, algae, and cyanobacteria; chlorophyll b, found in higher plants and green algae; chlorophyll c, found in diatoms, dinoflagellates, and brown algae; and chlorophyll d, found only in red algae.

Q66. Which reaction is catalyzed by the enzyme RuBisCO?

• A. Carboxylation of ribulose bisphosphate (RuBP)✓
• B. Conversion of triose phosphate (TP) to ribulose phosphate (RuP)
• C. Oxidation of giycerate-3-phosphate (GP)
• D. Reduction of glycerate-3-phosphate (GP)

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

Q67. Where does the Calvin Cycle occur?

• A. Stroma✓
• B. Cytosol
• C. Thylakoid Membrane
• D. No specific location

Explanation: The Calvin Cycle, also known as the dark reactions or light-independent reactions of photosynthesis, occurs in the stroma of the chloroplasts. The chloroplast is an organelle found in plant cells and some other eukaryotic cells, and it is the site of photosynthesis.

Q68. Syphilis is caused by:

• A. Coccus
• B. Bacillus
• C. Spirillum
• D. Spirochete✓

Explanation: Syphilis, systemic disease that is caused by the spirochete bacterium Treponema pallidum. Syphilis is usually a sexually transmitted disease, but it is occasionally acquired by direct nonsexual contact with an infected person, and it can also be acquired by an unborn fetus through infection in the mother.

Q69. Only one ovary is functional at a time in:

• A. Human
• B. Eagle
• C. Chicken✓
• D. Pigeon and human

Explanation: Unlike most female animals, which have two functioning ovaries, the chicken usually has only one. The right ovary stops developing when the female chick hatches, but the left one continues to mature.

Q70. Which of the following types and functions of the neuron is correct?

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

Explanation: Sensory neuron function to carry the sensory information to the CNS. Interneurons transfer impulses from sensory to motor neuron remaining within the CNS. Motor neurons are neurons that transmit impulses from CNS to the effectors.

Q71. During feedback inhibition, which of the following structural part of enzyme is involved?

• A. Active site
• B. Binding site
• C. Catalytic site
• D. Allosteric site✓

Explanation: Feedback inhibition is usually accomplished through something called an “allosteric site” – a site on an enzyme, that changes the shape of an enzyme, and subsequently, the behavior of the active site.

Q72. The function of calcium ions in muscle contraction is to:

• A. polarize visible light
• B. Aid in the transmission of nerve impulse
• C. Bind to troponin molecule and cause them to move✓
• D. Bind to tropomyosin molecule and cause them to form cross bridges

Explanation: Calcium ions bind to troponin (troponin C, to be precise), causing it to change shape, resulting in moving tropomyosin away from the actin binding sites on the myosin molecule in the thick filament, enabling cross bridge formation. It is important to note that troponin and tropomyosin are bound together, whereby tropomyosin directly blocks the binding sites on the actin molecule, while troponin binds to calcium ions which results in the movement of tropomyosin, away from the binding site. Therefore, option C is correct.Option A describes a feature which is irrelevant to the scenario. The I band of muscle fibers appear isotropic in polarized light, while A band appear anisotropic in polarized light.Option D is incorrect because Calcium does not bind to tropomyosin, it binds to troponin.

Q73. 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 faciliated diffusion
• D. move into the cell by faciliated diffusion✓

Explanation: As the question mentions there is a high concentration of sodium ions outside the cell that means 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.

Q74. Which of the following statements is a correct distinction between autotrophs and heterotrophs?

• A. Only heterotrophs require chemical compounds from the environment
• B. Cellular respiration is unique to heterotrophs
• C. Only heterotrophs have mitochondria
• D. Autotrophs but not heterotrophs can nourish themselves begining with nutrients that are entirely inorganic✓

Explanation: Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic. Heterotrophs depend on autotrophs either directly or indirectly.OPTION A: Autotroph needs chemical compound from environment.OPTION B: Cellular respiration is present in both not only heterotrophy as both of them requires energy in form of ATP which is formed by cellular respiration.OPTION C: Both have mirochondria in their cells which generates energy for cells and work as power house of cell.OPTION D: Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 and other nutrients that are inorganic.

Q75. Select the correct statement.

• A. The vertebral column has 10 thoracic vertebrae.
• B. The joint between adjacent vertebrae is a fibrous joint.
• C. A decreased level of progesterone causes osteoporosis in old people.
• D. Accumulation of uric acid crystals in joints causes their inflammation✓

Explanation: Thoracic vertebrae are 12 in numbers.Joints between adjacent vertebrae are cartilagenous joints and the opposing surfaces are connected by fibrocartilage which allows very little movement. Osteoporosis is a disease characterised by low bone mass and loss of bone tissue that may lead to weak and fragile bones. Osteoporosis occurs when there is an imbalance between new bone formation and old bone resorption. In osteoporosis, the osteoblastic (bone forming) activity in the bone usually is less than normal and consequently the rate of bone deposition is depressed. Estrogens inhibit osteoclastic (bone resorption) activity in the bones and therefore stimulate bone growth. Gout occurs when urate crystals accumulate in your joint, causing the inflammation and intense pain of a gout attack hence it is the correct option.

Q76. Which of these enzymes works best at a pH of 9.70?

• A. Arginase✓
• B. Pancreatic enzyme
• C. Catalase
• D. Chymotrypsin

Explanation: B. pH 9.00C. pH 7.60D. pH 7.00-8.00

Q77. In the male reproductive tract, sperm cells follow a specific path. Which of the following do sperm cells enter after traveling through the epididymis?

• A. Urethra
• B. Seminiferous Tubules
• C. Ejaculatory duct
• D. Vas deferens✓

Explanation: The correct sequence for transport of sperm cells in male reproductive system is Seminiferous tubules → Rete testis → Vasa efferentia → Epididymis → Vas deferens → Ejaculatory duct → Urethra → Urethral meatus.

Q78. Which hormone causes the contraction walls of the uterus during the process of birth?

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

Explanation: During birth the oxytocin causes the smooth muscle in the uterine wall to contract. Growth hormone (GH) or somatotropin, also known as human growth hormones (hGH or HGH) in its human form, is a peptide hormone that stimulates growth, cell reproduction, and cell regeneration in humans and other animals.Follicle stimulating hormone is one of the hormones essential to pubertal development and the function of women's ovaries and men's testes. In women, this hormone stimulates the growth of ovarian follicles in the ovary before the release of an egg from one follicle at ovulation. Prolactin, also known as lactotropin (LTH), is a protein best known for its role in enabling mammals, usually females, to produce milk.

Q79. Deficient production of hormones by adrenal glands results in: .

• A. Cushing's syndrome
• B. Addison's disease✓
• C. Diabetes Mellitus
• D. Goiter
• E. Epilepsy

Explanation: When adrenal glands don't produce enough hormones, this can lead to adrenal insufficiency (Addison's disease).

Q80. Haemoglobin exhibits a:

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

Explanation: Haemoglobin has a quaternary structure. It consists of two pairs of different proteins, designated the α and β chains. There are 141 and 146 amino acids in the α and β chains of haemoglobin, respectively. As in myoglobin, each subunit is linked covalently to a molecule of heme.

Q81. The photosynthetic pigments of plants are arranged as clusters in thylakoid membranes. The reaction centers of these clusters consist of _ molecules.

• A. Chlorophyll✓
• B. ATP
• C. Carotenoids
• D. Glucose

Explanation: Option A, chlorophyll, is the correct answer because they are the photosynthetic pigment that comprises the reaction centers of these clusters, or photosystems 1 and 2. Light energy collected by the photosystem is transferred to the reaction center, which consists of chlorophyll molecules, after which an electron is excited and the subsequent steps of the light-dependent reaction of photosynthesis occur.Option B, ATP, is the universal energy carrier, which is one of the end products of the light-dependent stage of photosynthesis and is not present within photosystems (which are clusters of photosynthetic pigments).Option C, carotenoids, are photosynthetic pigments, that are present within photosystems, but their main purpose is to collect/trap more light energy (of a shorter wavelength) and transfer it to the central chlorophyll molecules. Their purpose is to enhance the efficiency of absorption of light energy.Option D, glucose, is the final end product of photosynthesis and as such not a component of photosystems or their reaction centers.

Q82. Glycolipids and glycoproteins have a structural role in which matrix structure of animal and bacterial cell?

• A. Extracellular✓
• B. Intracellular
• C. Both A and B
• D. Plasma membrane

Explanation: Glycoproteins and glycolipids have a structural role in the extracellular matrix of animals and bacterial cell walls. Both these conjugated molecules are components of biological membranes. The exocellular matrix (ECM) is a complex network of molecules that surrounds and supports cells. It is composed of a variety of molecules, including carbohydrates, proteins, and lipids. Glycolipids and glycoproteins are two important components of the ECM that play a variety of structural and functional roles.

Q83. Non-toxic vitamins include which of the following?

• A. Vitamin C
• B. Vitamin B
• C. Both A and B✓
• D. None of the above

Explanation: Vitamin B is important for our body because it keeps our hair eyes and skin healthy while vitamin C boosts collagen synthesis and immune function, making both not toxic and therefore option C is correct.

Q84. Pathway of energy used by muscles converted from food is:

• A. Food-ATP-creatine phosphate- protein
• B. Food-glycogen- ATP-creatine phosphate
• C. Food-glycogen-creatine phosphate- ATP✓
• D. Food-protein-creatine phosphate- ATP

Explanation: Muscles convert food to energy by first breaking down glycogen to glucose. Glucose is then used to form creatine phosphate which is then metabolized to form ATP.

Q85. Louis Pasteur discovered a vaccine against which disease first?

• A. Anthrax✓
• B. Smallpox
• C. Rabies
• D. HIV

Explanation: Pasteur discovered a vaccine against Anthrax first and then Rabies.The vaccine of smallpox was discovered by Edward Jenner.

Q86. 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: Since the molar ratio between oxygen and NO is 2. The amount of NO produced is twice the amount of O2 produced i.e 1.6 mol. The same molar ratio is between O2 and NO so the reacted moles are also 1.6 mol, leaving behind 2.4 moles of NO2. Hence the equation is:Kc= [NO]2 * [O2] /[NO2]2

Q87. Bond energy: I. Is the energy required to break a bond between two atoms in a diatomic molecule II. Is taken as the energy released in forming a bond form free atoms III. Is the measure of the strength of bond

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

Explanation: All of the above statements are correct, it is because bond energy is the amount of energy required to break a bond as well when this bond is formed the same amount of energy is released. It thus provides us with an estimate of the strength of the bond.

Q88. From four substances described below, which is most likely to be an ionic compound?

• A. Melting point 1500°C, molten substance is a poor electrical conductor
• B. Melting point 20°C, molten substance does not conduct electricity
• C. Melting point 150°C, molten substance does not conduct electricity
• D. Melting point 800°C, molten substance readily conducts electricity✓

Explanation: Ionic compounds have high melting points. They are poor conductors in solid state but very good conductors of electricity in molten state.

Q89. According to the law of mass action, “The rate of chemical reaction” is proportional to the:

• A. The amount of product formed.
• B. Product of the molar concentration of reactants.✓
• C. The initial concentration of reactants.
• D. Catalyst.
• E. Pressure.

Explanation: The speed at which the reactants are converted to products is called the rate of reaction. There are many factors that affect the speed of conversion of reactants into products: Nature of reaction: The state and number of reactants and complexity of reaction can affect the rate of reaction. Effect of concentration: From the law of mass action, the rate of reaction is directly proportional to the concentration of reactants, that is, the rate of reaction increases with the increase in the concentration of reactants. Pressure: The concentration of reactants can be increased by pressure. Hence, when pressure is increased the speed of reaction also increases. Catalyst: It can increase speed in both reverse and forward directions. This gives another path having low activation energy. Temperature: The reaction which takes place at a high temperature has more energy than a reaction at a low temperature. Now, we have to know what the law of mass action states which will give us a clearer answer to this question. Therefore, according to the law of mass action, “the rate of the chemical reaction is directly proportional to the product of the activities or concentrations of the reactants”. So, from this statement, we can conclude that the rate of reaction depends upon the concentrations of the reactants which increase the speed of reaction with the increase in the chemical reaction. Hence the correct option is B.

Q90. In Lucas test, tertiary alcohols form oily layer of alkyl halide:

• A. On heating
• B. Immediately✓
• C. After 5-10 minutes
• D. After 20 minutes

Explanation: Immediately due to the higher stability of the intermediate tertiary carbocation.

Q91. The number of sigma and pi bonds in 1-butene-3-yne?

• A. 5 sigma and 5 pi
• B. 7 sigma and 3 pi✓
• C. 8 sigma and 2 pi
• D. 6 sigma and 4 pi

Explanation: The number of sigma and pi-bonds in 1-butene 3-yne are 7 sigma and 3 pi. It has one C=C double bond which contains one pi bond. It has one C≡C triple bond which contains two pi bonds. It has 3 carbon carbon sigma bonds and 4 C−H pi bonds.

Q92. The addition of HBr to an unsymmetrical alkenes follows?

• A. Direct addition
• B. Markovnikov's addition✓
• C. Anti Markovnikov's addition
• D. Dehydration

Explanation: Since the alkene and the reagent (HBr) are both unsymmetrical markovnikov’s rule will be followed. According to which the negative part of the reagent ( bromide ion) will attach to the carbon with fewer hydrogen atoms. Dehydration is when a water molecule is removed i.e., from alcohols to form alkenes.

Q93. _ are prepared by passing hydrogen gas over hot alkali metals or alkaline earth metals?

• A. Covalent hydrides
• B. Ionic hydrides✓
• C. Borderline hydrides
• D. Metallic hydrides
• E. Complex hydrides

Explanation: Ionic hydrides can be prepared directly on passing hydrogen gas over hot alkali metals or alkaline earth metals. Ionic hydrides are solids.

Q94. Dissolution of ammonium nitrate in water is an endothermic process. Which of the following graphs shows how the temperature alters as the ammonium nitrate is added to water and then the solution is left at room temperature?

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

Explanation: Since it is an endothermic process it takes heat from the surrounding making the temperature fall below room temperature. The temperature then gradually then goes back to room temperature.

Q95. 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: Increasing the pressure favors the side where the volume of gases is less. Since NH3 lies at the product side where total moles (volumes) of gases is 2 as compared to volume on the left side (reactant side) which 4. Increasing the pressure favors the NH3 production. Catalyst does not favor any side it increases the forward as well as the backward rate of reaction. Hence the answer is D.

Q96. s - sp3 overlap occurs in _ molecule.

• A. CI3
• B. CH4✓
• C. HF
• D. HI

Explanation: The methane molecule has four equal bonds. In hybridization, carbon's 2s and three 2p orbitals combine to form four identical orbitals, now called the 'sp3' hybrid orbitals. Each of them interacts with the 1s orbital of the Hydrogen atoms, forming a sigma bond, thus giving us methane.

Q97. According to the collision theory of bimolecular reactions in gas phase, minimum amount of energy is required for an effective collision is known as:

• A. Heat of reaction
• B. Rate of reaction
• C. Has no effect on the reaction
• D. Energy of activation✓

Explanation: Minimum amount of energy in addition to average kinetic energy is called activation energy or minimum amount of energy which must be possessed by reactant to convert into product is called activation energy. OR Minimum amount of energy required for an effective collision is called activation energy.

Q98. Which is the only alkali metal that combines with nitrogen?

• A. Li✓
• B. Fr
• C. Cs
• D. K

Explanation: Answer: ALithium is the only alkali metal that reacts with nitrogen to form lithium nitride. This is amongst the peculiar properties of lithium.

Q99. Students calculated the cell voltage for the reaction, 𝐵𝑟2 + 2𝑁𝑎𝐶𝑙 ⟶ 2𝑁𝑎𝐵𝑟 + 𝐶𝑙2 through the formula 𝐸°𝑐𝑒𝑙𝑙= 𝐸°𝑟𝑒𝑑+ 𝐸°𝑜𝑥𝑑 the answer was negative. It means that:

• A. The reaction is non spontaneous and feasible
• B. The reaction is non spontaneous and not feasible✓
• C. The reaction is spontaneous and feasible
• D. The reaction is spontaneous and not feasible

Explanation: Negative E cell means that the reaction isn’t spontaneous and not feasible

Q100. Which of the following best describes the emission spectrum of atomic hydrogen?

• A. a discrete series of lines of equal intensity and equally spaced with respect to wavelength equally
• B. a series of only four lines
• C. a continuous emission of radiation of all frequencies
• D. several discrete series of lines with both intensity and spacings between lines decreasing as the wavenumber increases with each series.✓

Explanation: The emission spectrum of atomic hydrogen has been divided into a number of spectral series, with wavelengths given by the Rydberg formula. These observed spectral lines are due to the electron making transitions between two energy levels in an atom. These lines have decreasing spacings(as shown below)

Q101. The compound ‘leaf alcohol’ is partly responsible for the smell of new - mown grass CH3CH2CH=CHCH2CH2OH Leaf alcohol Which two compounds will be formed when ‘leaf alcohol’ is oxidized using hot, concentrated manganate (VII) ions?

• A. CH3CO2H and HOCH2CH2CH2CO2H
• B. CH3CO2H and HO2CCH2CH2CO2H
• C. CH3CH2CO2H and HO2CCH2CO2H✓
• D. CH3CH2CO2H and HOCH2CH2CO2H

Explanation: The answer is C as when the double bond breaks, based on the structure of both the carbons involved in the double bond, each having a hydrogen attached alongside an organic chain, aldehydes would be formed. Both the aldehydes would be oxidized to give carboxylic acid. CH3CH2COOH is formed plus COOHCH2CH2OH with the latter being a primary alcohol. It would be further oxidized to give a dicarboxylic acid which is HOOCCH2COOH, thus the answer is C.

Q102. The electrophilic reactions of Benzene are:

• A. Halogenation
• B. Nitration
• C. Sulphonation
• D. Alkylation and Acylation
• E. All of these✓

Explanation: The electrophilic substitution of benzene is the one where an electrophile substitutes the hydrogen atom of benzene. Basic examples of electrophilic substitution reaction of benzene are nitration, sulfonation, halogenation, Friedel Crafts alkylation, and acylation, etc.

Q103. What is the unit of Kw for water?

• A. Moles/dm³
• B. Mol²/L²✓
• C. Dm³/moles
• D. Dm³/moles²

Explanation: Kw = [H+] [OH-]The unit for Kw would be:Kw = [mol/L] [mol/L]= mol2/L2

Q104. Greater the mass of gas taken, greater will be slope of straight line. Because greater the _greater will be volume occupied.

• A. Pressure
• B. Temperature
• C. Number of moles✓
• D. All of these

Explanation: Option A is incorrect as greater pressure decreases the volume of a gas. Option B is incorrect as temperature increases so volume increases, however, the question is talking about the mass of the gas-only therefore the option is incorrect. Option C is correct as according to formula n × 24 = Volume increasing the "number of moles" increases volume.

Q105. Alkaline earth metal hydroxides decompose on heating. Which of the following reactions is a correct representation of this decomposition?

• A. A✓
• B. B
• C. C
• D. D

Explanation: Metal hydroxide decomposes to form metal oxide and liquid water.

Q106. The reaction: Cl2 + H2O→ HCl + HOCl is an example of:

• A. Oxidation reaction
• B. Reduction reaction
• C. Auto-oxidation and reduction reaction✓
• D. Substitution reaction
• E. Addition reaction

Explanation: Auto-oxidation and reduction reaction is a reaction in which the same element is oxidized as well as reduced. In the reaction given above, the Cl element reduces to Cl-(HCl) and oxidizes to Cl+(in HOCl).

Q107. Nascent hydrogen used in the formation of methane is obtained from the reaction of:

• A. NaHCO3 with Zn
• B. HCl with Zn✓
• C. KOH with Zn
• D. H2O with Zn
• E. CH3l with Zn

Explanation: Following are the reaction produces nascenthydrogen: Zn +HCl → ZnCl + [H]

Q108. If the value of 'Kc' is very large then, it shows that _ completed.

• A. Forward reaction✓
• B. Reverse reaction
• C. Equilibrium is maintained
• D. Kc is moderate

Explanation: If 'Kc' is a large number, it means that the equilibrium concentration of the products is large. In this case, the reaction, as written, will proceed to the right (resulting in an increase in the concentration of products).If 'Kc' is a small number, it means that the equilibrium concentration of the reactants is large.

Q109. The catalyst used for the formation by dehydration of alcohols?

• A. Concentrated HN3 at 140 C
• B. Concentrated H2SO4 at 140 C✓
• C. Hot H3PO4 at 180 C
• D. ZnCl2 at 450 C

Explanation: Concentrated sulfuric acid is the catalyst which is used in this reaction.

Q110. Which property of the Group II elements (magnesium to barium) and their compounds increases with an increasing proton (atomic) number?

• A. The magnitude of the enthalpy change of hydration of the metal ion
• B. The pH of the aqueous chloride
• C. The solubility of the sulphate in water
• D. The stability of the carbonate to heat✓
• E. The tendency to form complex ions

Explanation: The stability of metal carbonates increases down the group, so D is the correct option. Down the group enthalpy change of hydration of metal ion, pH of the aqueous chloride, solubility of sulphate, and tendency to form complex ions decreases so options A, B, C, and E are wrong.

Q111. The diagram shows a galvanic cell. The current will flow from:

• A. Hydrogen electrode to copper electrode✓
• B. Copper electrode to hydrogen electrode
• C. Hydrogen electrode to HCl solution
• D. CuSO4 solution to hydrogen electrode

Explanation: Copper is less reactive than hydrogen so it should gain electrons.

Q112. What is the cell reaction of Zn(s) | Zn2+(aq) 1M | Ni2+(aq) 1M | Ni(s) Zn2+(aq) + 2e- -> Zn(s), Eo = -0.76 V Ni2+(aq) + 2e- -> Ni(s), Eo = -0.25 V

• A. Ni2+ + Zn -> Zn2+ + Ni✓
• B. Zn2+ + Ni -> Ni2+ + Zn
• C. Zn2+ + Ni2+ -> Zn + Ni
• D. Zn + Ni -> Zn2+ + Ni2+

Explanation: In the given cell, Zn is oxidized to Zn2+ ions, and Ni2+ ions are reduced to Ni atoms. The anode is Zn, and the cathode is Ni. The electrons flow from the Zn electrode to the Ni electrode through the wire and the salt bridge. The overall reaction is: Zn(s) + Ni2+ (aq) → Zn2+ (aq) + Ni(s)

Q113. SiO2 is the only oxide that reacts with:

• A. HClaq
• B. KOHaq✓
• C. Steam
• D. SO3

Explanation: KOH(aq)- Silicon dioxide is acidic but will only react with strong bases of hot concentrated KOH/NaOH due to its strong and extensive covalent bonds.

Q114. The heat of combustion of hydrocarbon is very useful source of heat and power, Considering the combustion reaction given below. CH4(g) +O2(g) →CO2(o) + 2H2O △H for the reaction is.

• A. △H = -213 kcal/mole✓
• B. △H= 231 kcal/mole
• C. △H= 426 kcal/mole
• D. △H= 312 kcal/mole

Explanation: Enthalpy of combustion of methane is -890KJ/mol. 1KJ = 0.239Kcal 890KJ= 212.715Kcal

Q115. Which of the following esters give a Jasmine Flavour?

• A. Ethyl Acetate
• B. Octyl Acetate
• C. Amyl Butyrate
• D. Benzyl Acetate✓

Explanation: Benzyl Acetate has a pleasant sweet aroma reminiscent of jasmine, and is used as a flavoring agent in jasmine or apple flavors to various cosmetics and personal care products like lotions, hair creams etc.

Q116. The only thing which can predict that if the reaction will be spontaneous or nonspontaneous is:

• A. Enthalpy change
• B. Free energy of the system✓
• C. Energy Change
• D. Temperature Change

Explanation: Free energy of the system also known as the Gibbs free energy determines if the reaction is spontaneous or not. The formula for Gibss free reaction = enthalpy change- T(entropy change).If Gibbs free reaction is 0 or less, then the reaction is spontaneous.

Q117. Which of the following does NOT belong to AB4 type molecule:

• A. H2S
• B. H2O
• C. SnCl2✓
• D. PH3

Explanation: SnCl2 does not belong to the AB4 group while the rest of the molecules belong to the AB4 group.H2O and H2S are AB 4 type molecules with two lone pairs. PH3 is an AB 4 molecule with one lone pair. SnCl2 is an AB 3 molecule with one lone pair and two bond pairs.

Q118. The strongest acid among the following is?

• A. Carbolic acid
• B. H2O
• C. Methanol
• D. Butanoic acid✓

Explanation: OPTION A: Carbolic acid is a weak organic acid with a pKa of around 10. It is a slightly acidic compound and is a weaker acid than water.OPTION B: Water is a neutral compound with a pH of 7, but it can act as a weak acid in certain solutions. This is due to the presence of Hydronium ions (H3O+) that form when water dissolves in acidic solutions.OPTION C: Methanol is a weak organic acid with a pKa of around 15. It is a weaker acid than water and phenol. OPTION D: Butanoic acid is a stronger organic acid with a pKa of around 4.5. It is a stronger acid than water, phenol, and methanol.

Q119. Which of the following will react with water?

• A. CHCl3
• B. Cl3CCHO✓
• C. CCl4
• D. ClCH2CH2Cl

Explanation: Cl3CCHO will react with water. Water is a polar solvent. Like dissolves like. A polar solvent will be dissolved in a polar and a non-polar compound will be dissolved in a nonpolar solvent. CCl4, ClCH2CH2Cl are non-polar. So they will not be able to dissolve in water. Cl3CCOOH will form hydrogen bonds with water due to which it will dissolve in water. Such hydrogen bonding is not present in the case of CHCl3. Chloral (Cl3CCHO) reacts with water to form chloral hydrate, CCl3CH(OH)2

Q120. For a chemical reaction to occur, particles that collide should:

• A. All of these✓
• B. Have proper orientations
• C. Have proper energies
• D. Be in a homogenous mixture

Explanation: The collision theory states that for particles to take part in a chemical reaction, they must collide with one another, have sufficient energies, proper orientation, and should be in a homogenous mixture.

Q121. If we balanced the following reaction , what is the net ionic charge on the right side of the equation? _H+ +_ MnO4- + _ Fe2+ →_ Mn2+ + _ Fe3+ + _ H2O

• A. +5
• B. +7
• C. +10
• D. +17✓

Explanation: Correct option is '+17'. This will be balanced using the ion-electron method. Calculte the net charge on the RHS of the equation which should be the same for the LHS. The net ionic charge on either side must be zero for the equation to be balanced.

Q122. If a molecule MX3 has zero dipole moment, the sigma bonding orbitals used by M are:

• A. Pure p
• B. sp hybrids
• C. sp2 hybrids✓
• D. sp3 hybrids

Explanation: In order for MX3 molecule to have zero dipole moment, it must have a symmetrical shape which in this case can only be trigonal planar. The bond angle in this case between X-X would be 120o so it should have sp2 hybrids.

Q123. In the following reaction sequence, product D will be:

• A. 1 - propanol
• B. Propanoic acid
• C. 2 - propanol✓
• D. Mixture of methanol and ethanol

Explanation: The above reaction scheme describes dehydrohalogenation of the alkyl halide into an alkene, followed by hydration of the alkene. The first step involves the reaction of propyl bromide with alcoholic KOH, which will result in elimination or dehydrohalogenation, whereby the halogen atom and adjacent carbon atom's hydrogen atom is removed, resulting in the formation of a double bond between the two carbons, forming propane, which is product C. Propene is acted upon by aqueous H2SO4, which implies hydration or addition of H2O, resulting in the formation of two products; the major product which is 2-propanol and the minor product which is 1-propanol so, the major product is the preferred option, i.e. option C.

Q124. In which of the following cases are the benzene rings isolated?

• A. Naphthalene
• B. Phenanthrene
• C. Anthracene
• D. Triphenylmethane✓

Explanation: The structure of Triphenylmethane is as follows:

Q125. 1,4-dimethyl benzene is called as _.

• A. Ortho-xylene
• B. Para-xylene✓
• C. Para-methyl toluene
• D. Meta-methyl toluene

Explanation: Xylene is any of three organic compounds with the formula (CH₃)₂C₆H₄. They are derived from the substitution of two hydrogen atoms with methyl groups in a benzene ring. In ortho benzene, the two methyl substituents bonded to adjacent carbon atoms of a benzene ring i.e. carbon no. 1 and 2. In para-xylene, one methyl group is at position 1 and other at 4.

Q126. The solubility product of AgCl is 2.0x10-10 mol-2 dm-6. The maximum concentration of Ag+1 ions in the solution is:

• A. 2.0x10-12 mol dm-3
• B. 1.41x 10-5 mol dm-3✓
• C. 1.0x10-12 mol dm-3
• D. 2.5x10-10 mol dm-3

Explanation: To find out the concentration, We know that solubility product is 2 x 10-10 so, AgCl = (Ag+2) (Cl-) 2 x 10-10 = (x) (x) 2 x 10-10 = x2 X = 1.4 x 10-5

Q127. The rate constant of a first-order reaction is 3 x 10-6 per second. If the initial concentration is 0.10 M, the initial rate of reaction is:

• A. 3 x 10-3 Ms-1
• B. 3 x 10-4 Ms-1
• C. 3 x 10-6 Ms-1
• D. 3 x 10-7 Ms-1✓

Explanation: Rate constant of the first order reaction (K) = 3 x 10-6 per sec and initial concentration [A] = 0.10 M. We know that initial rate constant: K[A] = 3 x 10-6 x 0.10 = 3 x 10-7 Ms-1

Q128. Identification tests for functional groups of organic compounds are associated with specific observations. Tollen’s reagent is an ammoniacal silver nitrate solution, which is used for the identification of a functional group X with an observation O. Identify X and O.

• A. X = Aldehyde O = Silver mirror✓
• B. X = Ketone, O = Grey precipitate
• C. X = Ketone, O = Silver mirror
• D. X = Aldehyde O = Red precipitate

Explanation: Tollens reagent test is also known as the silver mirror test. It cannot react with ketones but it reacts with aldehydes, thereby identifying the aldehyde functional group. Upon reacting, the silver precipitates as a silver mirror which coats the bottom of the test tube. Hence, option A is the correct answer as it is the only one with both correct functional group and observation.

Q129. Benzene can be prepared from:

• A. From Petroleum
• B. From Coal
• C. From Acetylene
• D. From Phenol
• E. All of these✓

Explanation: This is the following explanation:

Q130. Choose the right molecule.

• A. CH3
• B. CO
• C. H2O
• D. NH3✓

Explanation: Standard structural formula of Ammonia

Q131. The enthalpy change of the reaction H2(g) + ½ O2 -> H2O (l) under standard conditions is:

• A. Enthalpy change of formation of water
• B. Enthalpy change of neutralization
• C. Both; Enthalpy change of combustion of Hydrogen and enthalpy change of formation of water✓
• D. Enthalpy change of combustion of Hydrogen

Explanation: Since 1 mole of H2 is being combusted, it can be called enthalpy change of combustion of H2. Also, 1 mole of water is being formed from its constituent elements under standard state so it can also be called standard enthalpy change of formation of water.

Q132. The method which is used on an industrial scale for production of alcohol from alkene is:

• A. Hydrohalogenation of alkenes
• B. Dehydration of alkenes
• C. Hydration of alkenes✓
• D. Hydroxylation of alkenes

Explanation: Option A: Gives alkyl halide, by breaking a double bond followed by the electrophilic addition of hydrogen and halogen. Option B: Alkenes can not be dehydrated. Option C: Alkenes, upon reaction with protic acids and other catalysts, tend to gain a molecule of H2O to form Alcohol, hence Option C is correct. Option D: Hydroxylation of alkene is a process in which the alkene is converted to glycol.

Q133. For a sub shell I=2 and m = -2,-1, 0,+l,+2,it implies that it has _ space orientation.

• A. One
• B. Two
• C. Three
• D. Five✓

Explanation: Option D is correct as the subshell with l=2 is the d subshell with "5" orbitals.

Q134. Which of the following compounds react slower than benzene in electrophilic substitution reaction?

• A. Nitrobenzene✓
• B. Phenol
• C. Aniline
• D. Toluene

Explanation: An electrophilic substitution reaction is a chemical process in which a compound's functional group is replaced by an electrophile. In this case, the displaced group is a hydrogen atom.The derivatives of benzene which have activating groups attached push electron density towards the ring, making it more susceptible to electrophilic attack and consequently, more rapid reactions.Similarly, the derivatives of benzene which have a deactivating group attached withdraw electron density away from the ring, making it less susceptible to electrophilic attack and consequently, slower reactions. Nitrobenzene is an example of such a derivative which is less reactive than benzene because the nitro group is a deactivating group (meta-directing). Therefore, option A is the correct answer.The table below lists some common groups and whether they are activators/deactivators and ortho para/meta directing.

Q135. X is a salt that decomposes in water. What is the reason for its decomposition?e- + X3+ → X2+ Ecell = 1.91 V

• A. This potential oxidizes salt
• B. This potential oxidizes water✓
• C. This potential reduces water
• D. None of these

Explanation: O2 + 4H+ + 4e -> 2H2O is the standard electrode potential equation of water having a value of 1.23V. The reduction of the X3+ ions has the standard potential of 1.91V which is greater than the standard potential of water. This difference in standard potential would allow the X3+ to be reduced as it has a higher E naught thus its reduction is preferential. As X3+ is being reduced and since reduction-oxidation happens simultaneously, water is oxidized to give O2 gas. Based on this idea, the answer is B.

Q136. When Gypsum is heated to about 100° C, it losses some water of crystallization and becomes:

• A. Epsom salt
• B. Kieserite
• C. Plaster of Paris✓
• D. Bleaching Powder
• E. Caustic soda

Explanation: When gypsum is heated at 373 K, it loses its water of crystallization or all the water molecules and becomes calcium sulphate hemihydrate. Gypsum is converted to “Plaster of Paris”. In fact, gypsum is Plaster of Paris and when heated, this Plaster of Paris melts to give Gypsum.

Q137. If the nuclear radius of Al-27 is 3.6 fm, the approximate nuclear radius of Cu-64 in fermi is_.

• A. 1.2 gm
• B. 2.4 fm
• C. 3.6 fm
• D. 4.8 fm✓

Explanation: R1/R2 = (A1/A2)^⅓ 3.6/R2 = (27/64)^⅓ "R2 = 4.8"

Q138. In "Down Cells", the cathode is made up of:

• A. Graphite
• B. Copper
• C. Iron✓
• D. Inert material

Explanation: The Downs process is a method for the commercial preparation of metallic sodium, in which molten NaCl is electrolyzed in a special apparatus called the Downs cell.The Downs cell uses a carbon anode and an iron cathode.Hence, C is the correct option.

Q139. Which step should be repeated over and over to get a variety of substituted products?

• A. None of these
• B. Termination
• C. Propagation✓
• D. Initiation

Explanation: Radical chain reactions have three distinct phases: initiation, propagation, and termination. The initiation phase describes the step that initially creates a radical species. The propagation phase describes the ‘chain’ part of chain reactions. Once a reactive free radical is generated, it can react with stable molecules to form new free radicals. These new free radicals go on to generate yet more free radicals, and so on. This step, therefore, gives a variety of substituted products. The termination phase occurs when two free radical species react with each other to form a stable, non-radical adduct.

Q140. When a body of weight ‘W’ is kept suspended by a string, the weight of the body pulls the string downwards, while the string pulls the body upwards with an equal force, this force is called?

• A. The frequency of the string
• B. The displacement of the string
• C. The tension of the spring✓
• D. The wavelength of the string

Explanation: The force acting opposite to the weight of the body attached to the string is called the tension force.

Q141. Law of conservation of momentum states that: I. If there is no external force applied to a system, then the total momentum of that system remains constant II. If there is an external force applied to a system, then the total momentum of that system remains constant III. If there is no external force applied to a system, then the total momentum of that system keeps changing

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

Explanation: If there is no external force applied to the system, then the total momentum of that system remains constant. If an external force is applied then the total momentum will change.

Q142. What will happen in a time of 7 hours, if a radioactive substance has an average life of 7 hours?

• A. Half of the active nuclei decay
• B. Less than half of the active nuclei decay
• C. More than half of the active nuclei decay✓
• D. Total nuclei decay

Explanation: Option A) Half of the active nuclei is incorrect because the half-life is defined as the time it takes for half of the active nuclei to decay. So, after one half-life, half of the active nuclei will decay. Option B) Less than half of the active nuclei decay is incorrect because the half-life is defined as the time it takes for half of the active nuclei to decay. So, after one half-life, half of the active nuclei will decay.Option C) The mean life of an element equals the half-life of the substance divided by the natural logarithm of 2 which is about 0.693. Since the entire radioactive nuclei can never decay, more than half of the nuclei will decay.Option D) Total nuclei decay is incorrect because radioactive decay is a random process and cannot be predicted with certainty. However, the concept of half-life allows us to make statistical predictions about the decay process.

Q143. A 220 V main supply is connected to a resistance of 100 k ohms. The effective current is _.

• A. 2.2mA✓
• B. 2.2/v2 mA
• C. 2.2 x v2 mA
• D. None of the above

Explanation: We know that,V = IRI = VRI = 220V/100k.ohmI = 2.2 mA

Q144. Consider a car is travelling for one hour. Which of the following cases has the greatest average velocity in the east-direction?

• A. Car travels 20 km due east
• B. Car travels 20 km due east, then turns around and travels 40 km due west
• C. Car travels 70 km due east✓
• D. Car travels 30 km due west, then turns around and travels 30 km due east

Explanation: Average velocity = total displacement / total timeAs the time is same, so averge velocity will depend on total displacemnent.AVERAGE VELOCITY ∝ TOTAL DISPLACEMENTAs, the maxiumum displacement is in option C , so this is right option

Q145. The values of electric intensity will _ due to the presence of dielectric medium:

• A. Increase
• B. Increase exponentially✓
• C. Decrease
• D. Remain same

Explanation: The strength of the electric field is reduced due to the presence of dielectric. If the total charge on the plates is kept constant, then the potential difference is reduced across the capacitor plates.

Q146. The centripetal acceleration is maximum when radius r is:

• A. Increasing
• B. Decreasing✓
• C. Constant
• D. None of these options are correct

Explanation: We know that centripetal acceleration (a) = v2/r where v is the linear speed and r is the radius. If v is constant, then a is inversely proportional to r. So, a will be maximum when r is decreasing.

Q147. The angular measurement is known as _ measurement

• A. parameter
• B. area
• C. circumference✓
• D. all of these

Explanation: As θ= Angular displacement or measurement Explanation for this question will be added soon.As θ= Angular displacement or measurement S= arc length or circumference r= radius of circle Since θ= S/r Hence angular displacement is related to circumference or arc length as rhey are directly related.

Q148. How fast an H+ ion should move in magnetic field 2.5x10-3 T such that magnetic force equal its weight?

• A. 6 x 10-5 m/s
• B. 4.5 x 10-5 m/s
• C. 3.3 x 10-6 m/s
• D. 4 x 10-5 m/s✓

Explanation: According to given condition Force = Weight evB = mg v = mg/eB Putting the values, we obtain

Q149. What is an optically active medium?

• A. A medium which absorbs light
• B. A medium which absorbs polarized light
• C. A medium which can rotate the plane of polarization✓
• D. A medium which refracts polarized light

Explanation: An optically active medium can rotate the plane of polarization of a beam of light that is passed through it.

Q150. When a car travelling with constant velocity passes a stationary observer, the observer hears a change in the frequency of sound emitted by the car. Which statement is correct ?

• A. The change in frequency is greater as a car moves away than as it approaches.
• B. The greater the speed of the car, the greater the change in observed frequency.✓
• C. The observed frequency is lower as the car moves toward the observer and higher as the car moves away from the observer
• D. The volume of the sound heard by the observer does not change as the car approaches.

Explanation: Wave speed is the distance a wave travels in a given amount of time, such as the number of meters it travels per second. Wave speed is related to wavelength and wave frequency by the equation: Speed = Wavelength x Frequency so as the speed increases the observed frequency also increases.

Q151. Faraday law states that the rate of change of magnetic flux is equal to

• A. electromotive force✓
• B. induced current
• C. induced flux
• D. induced magnetic field

Explanation: Faraday's law stated that" The average EMF induced in a conducting coil of N loops is equal to the negative of the rate at which the magnetic flux through the coil is changing with time."

Q152. A row of 25 decorative lights, connected in series, is connected to a main transformer. When the supply is switched on, the lights do not work. The owner uses a voltmeter to test the circuit. When the voltmeter is connected across the third bulb in the row, a reading of zero is obtained. Which of the following cannot be the only fault in the circuit?

• A. The filament of one of the other bulbs has broken
• B. The filament of the third bulb has broken.✓
• C. The fuse in the mains transformer has blown.
• D. There is a break in the wire from the supply to the transformer.

Explanation: According to the Ohms Law (V=IR), voltage is directly related to resistance (keeping same current). If the third filament is broken, the voltage across that bulb will not be zero but it will be maximum due to maximum resistance. There should be another issue leading to the voltage drop.

Q153. Laplace's correction to Newton’s formula is based on the fact that the compressions and rarefactions occur as _.

• A. Adiabatic process✓
• B. Isothermal process
• C. Isochoric process
• D. Isobaric process

Explanation: Newton assumed that the pressure–volume changes that occur when a sound wave travels through the gas are isothermal. Laplace was subsequently able to obtain agreement between theory and experiment by assuming that pressure–volume changes are adiabatic.

Q154. A parachutist is falling constant terminal velocity. Which statement is not correct?

• A. Gravitational potential energy is converted into kinetic energy of the air.
• B. Gravitational potential energy is converted into kinetic energy of the parachutist.✓
• C. Gravitational potential energy is converted into thermal energy of the air
• D. Gravitational potential energy is converted into thermal energy of the parachutist.

Explanation: Terminal velocity reaches when the force of gravity acting on the object is equal to the air resistance or viscous force of air on the body. Air resistance is a major factor contributing in a falling object to reach terminal velocity as it can easily contribute to the speed at which the body thus both kinetic energy and potential energy cannot be equated.

Q155. During radioactive decay of a nucleus zXA, β emission takes place along with the daughter nucleus. Because of this beta particle emission, the mass number (A) of the parent nucleus:

• A. Remains constant✓
• B. Decreases by 1
• C. Increases by 1
• D. Decreases by 2

Explanation: On emitting a β particle the number of nucleons in the nucleus (i.e. protons and neutrons) remains same, but the number of neutrons is decreased by one and the number of protons is increased by one. If a radioactive nucleus P with mass number A and atomic number Z emits a beta particle to form a daughter nucleus Q with mass number A and atomic number Z+1. (a) Atomic number Z is not conserved. It is increased by 1. (b) Mass number A is conserved. Result: So, from the above discussion it is clear thwt mass number (A) remains constant after the beta decay and not increased or decreased .

Q156. The earth rotates on its axis once a day. Suppose, by some process the earth contracts so that it’s radius is only half as large as at present, then how long the earth will take to complete it’s rotation?

• A. 24 hours
• B. 18 hours
• C. 6 hours✓
• D. 12 hours

Explanation: Here we assume that the mass of earth remains the same, moment of the inertia of the earth rotating about its axis is : I=⅖ MR^2-------eq1 Angular velocity of the earth is: ω=2pi/T-------eq 2 When the radius is reduced to half, The new moment of inertia is I=2/5MR^2=2/5M(R/2)^2----eq3 New time period is T’ an angular velocity is: ω’=2pi/T’ Applying the law of conservation of angular momentum, we get: Iω=I’ω’ From eq 1,2,3, and 4 we get (2/5MR^2)*(2pi/T)=[2/5M(R/2)^2]*(2pi/T’) ->T’=T/4 But T=24 hrs T=24/6=6 hrs

Q157. A sphere of charge +Q is fixed in a position. A smaller sphere of +q is placed near the larger sphere and released from the rest. The small sphere will move away from the large sphere with?

• A. Decreasing velocity and decreasing acceleration
• B. Decreasing velocity and increasing acceleration
• C. Decreasing velocity and constant acceleration
• D. Increasing velocity and decreasing acceleration✓
• E. Increasing velocity and increasing acceleration

Explanation: Since both the charges have the same charges they have the force of repulsion, so they move away from one another. Because the force is acting on them it does provide acceleration, causing the velocity to increase. But since the distance between the two charges is increasing the magnitude of the force acting on both of the objects decreases, causing the acceleration to decrease.

Q158. A standing-wave pattern is formed when the length of the string is:

• A. an odd multiple of quarter wavelength
• B. an integral multiple of quarter wavelength
• C. an integral multiple of wavelength
• D. an integral multiple of half wavelength✓

Explanation: A standing wave pattern is formed when the length of the string is an integral multiple of half wavelength.

Q159. A metal cube with sides of length “𝑎” has electrical resistance 𝑅 between opposite faces. What is the resistance between the opposite faces of a cube of the same metal with sides of length 3𝑎?

• A. 9𝑅
• B. 3𝑅
• C. R/3✓
• D. 𝑅/9

Explanation: the resistance can be found by the relation R=pL/A p(resistivity) In this case L=a and A=a2 soR=p 1/aWhen L=3a then A=9a2So R=p 1/3a Hence 1/3 times

Q160. A constant force F= 2i + 3j +4k is applied on a body what will be the work done to move a body 5 m in z-direction

• A. 0
• B. 10 J
• C. 45 J
• D. 20 J✓

Explanation: W=F.S W=(2i+3j+4k) . (5k) W= 4x5 = 20J As, i.i=j.j=k.k = 1 i.j=j.k=k.i = 0

Q161. In the case when the electrons lose all their kinetic energy (K.E) in the first collision, the X-ray photon emitted has the following set of frequency and wavelength?

• A. fmax, λmin✓
• B. fmax, λmax
• C. fmin, λmax
• D. fmin, λmin

Explanation: The energy of X rays is given by ℎ𝑐/λλ is minimum when all kinetic energy is converted to energy of X-rays. Since 𝑐 = 𝑓λ for X-rays, if λ is minimum, frequency is maximum.

Q162. If a charged particle moves through a magnetic field perpendicular to it, _.

• A. Both momentum and energy of particle change
• B. Momentum as well as energy are constant
• C. Energy is constant but momentum changes✓
• D. Momentum is constant but energy changes

Explanation: If a charged particle moves through a magnetic field perpendicular to it, it acquires circular motion. During circular motion, the velocity of the body changes at each point. As momentum depends upon the velocity, by the equation, P = mv, the momentum also changes with the velocity. Only the direction of the velocity is changing, whereas its magnitude remains constant. From the equation of Kinetic energy, K.E = ½ mv², it is evident that the square of the velocity means no change in magnitude.

Q163. In the diagram below, the displacement of an oscillating particle is plotted against time. What does the length ‘PR’ on the time axis represent?

• A. Twice the frequency
• B. Half the period✓
• C. Half the frequency
• D. Twice the period

Explanation: The time period of the wave is the time between two consecutive troughs or two consecutive crests. In the given diagram you can see the distance between a trough and a crest which means its half a period.

Q164. A particle having mass m and momentum p, the kinetic energy of the particle is given by:

• A. p^2/m
• B. p/m
• C. p^2/(2m)✓
• D. m^2/p

Explanation: We know that:P=mv From here v=p/mWe know know that K.E=0.5mv^2K.E=0.5m(p/m)=p^(2/2m)

Q165. The following question belongs to the topic of momentum:

• A. Current
• B. Length
• C. Angular momentum✓
• D. Torque
• E. Displacement

Explanation: In three dimensions, the angular momentum for a point article is a pseudovector r × p, the cross product of the particle's position vector r (relative to some origin), and its momentum vector.

Q166. If a car collides with a housefly, what will be the magnitude of the force experienced by the housefly?

• A. Much greater than the force experienced by the car
• B. Much lesser than than the force experienced by the car
• C. Same as the force experienced by the car✓
• D. 10 times less than the force experienced by the car

Explanation: Yes, the same amount of force is imparted on each of them at the moment of the collision. However, one is affected much more than the other.Instead of thinking in terms of accelerating cars and flies, assume each has a constant velocity. At the moment of impact, each of them undergoes an acceleration (in the negative direction, so we usually call it deceleration) proportional to the force F of the impact. F is the same for both objects.Now, according to Newton's third law, at the moment of impact, the force that the car imparts on the fly is exactly equal to the force that the fly imparts on the car. Also, according to Newton's second law, the force is equal to mass times acceleration. As such, the train hits the fly with a massive amount of force, equal to the acceleration times the mass of the train.Results:The magnitude of force experienced by the housefly is the same as that experienced by the car neither less nor more because Newton's 3rd law is applicable here.

Q167. Time varying magnetic field creates electric field, this is called --------

• A. Electric induction
• B. Magnetic induction
• C. Electromagnetic induction✓
• D. Dipole induction

Explanation: Option C is correct since electromagnetic induction is a process in which a conductor is put in a particular position and the magnetic field keeps varying or the magnetic field is stationary and a conductor is moving. This produces a Voltage or EMF (Electromotive Force) across the electrical conductor.

Q168. Internal resistance of a battery is _ ohm if E = 10V , V = 9V, I = 1A

• A. 1✓
• B. 0.1
• C. 0.01
• D. None of these

Explanation: We know that E = V + Ir Where r is the internal resistance. Subsituting the values in the formula: 10 = 9 + 1r 1 = 1r r = 1 ohm

Q169. When a charged particle is projected perpendicular to a magnetic field:

• A. Its path is circular in a plane perpendicular to the plane of magnetic field✓
• B. The speed and kinetic energy of the particle remains constant
• C. The velocity and momentum of the particle changes only in direction
• D. The time period of revolution, angular and frequency of revolution is independent of velocity of the particle and radius of circular path

Explanation: When a charged particle is projected perpendicular to a magnetic field, The path of particle is circular in a plane perpendicular to the plane of magnetic field. The correct option is A.

Q170. The sound waves of frequency more than 20 khz are termed as:

• A. Supersonic
• B. Audible
• C. Infrasonic
• D. Ultrasonic✓

Explanation: Ultrasonic waves are sound waves whose frequencies are higher than those of waves normally audible to the human ear. ultrasonics, vibrations of frequencies greater than the upper limit of the audible range for humans—that is, greater than about 20 kilohertz.

Q171. Two spherical balls of 2.0 kg and 3.0 kg masses are moving towards each other with velocities of 6 m/s and 4 m/s respectively. What must be the velocity of the smaller ball after the collision, if the velocity of the bigger ball is 3 m/s?

• A. 1.5 m/s
• B. 2.5 m/s
• C. 3.5 m/s
• D. -4.5 m/s✓
• E. 5.5 m/s

Explanation: Initial velocity of 2kg mass = 6m/s Initial velocity of 3kg mass = -4m/s [-ve sign shows opposite direction] Final velocity of 3kg mass = 3m/s We have to find final velocity of 2kg mass ◈ In any kind of collision, Linear momentum of system is conserved. Momentum is measured as the product of mass and velocity. ➝ Initial P = Final P ➝ m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂ ➝ (2×6) + (3×-4) = (2v₁) + (3×3) ➝ 12 - 12 = 2v₁ + 9 ➝ 2v₁ = -9 ➝ v₁ = -9/2 ➝ v₁ = -4.5 m/s Hence, small ball will move at velocity of -4.5m/s in opposite direction after collision.

Q172. Michelson's interferometer is an instrument that can be used to measure _.

• A. Speed
• B. Frequency
• C. Distance✓
• D. Amplitude

Explanation: Option C is correct since the distance is measured by the wavelength of the light. Options A, B, and D are incorrect since the device failed to measure the speed of light, whereas frequency and amplitude cannot be measured.

Q173. If a charged particle is at rest but we are seeing it from a train then we observe ----------------

• A. Electric field
• B. Magnetic field
• C. Both fields✓
• D. None of these

Explanation: Option C is correct since for us the charge is moving and creating a magnetic field along with electricity.

Q174. A wave passes through a medium, and each particle of the medium performs 100 complete vibrations in 5 seconds. What is the frequency of the wave?

• A. 2 Hz
• B. 20 Hz✓
• C. 4 Hz
• D. 40 Hz

Explanation: Frequency is the number of cycles/oscillations per second. Therefore f = 100/5 = 20 Hz. Hence Option B is correct.

Q175. The Lenz's law refers to:

• A. Induced current✓
• B. Induced potential
• C. Motional emf
• D. All of these

Explanation: 'The induced electromotive force', with different polarities, induces a current whose magnetic field opposes the change in magnetic flux, through the loop, in order to ensure that original flux is maintained, through the loop, when current flows in it. Since, Lenz's law discusses the electric current induced in a conductor, this option is incorrect.

Q176. A particle, carrying a charge of 5e, falls through a potential difference of 25 V. What would be energy acquired by the particle in ‘J’.

• A. 1.6 x 10-19 J
• B. 125 J
• C. 125 x 10-19 J
• D. 125 x 1.6 x 10-19 J✓

Explanation: Electric Potential Energy = Electric Potential x Charge Charge = 5 x 1.6 x 10-19 C Electric Potential Energy = 25V x (5 x 1.6 x 10-19) C This could be manipulated to give us (125 x 1.6 x 10-19) J, which is Option D.

Q177. If the velocity of a charged particle and magnetic field are at a fixed angle that is not 90 degrees, then the path will be:

• A. Circular
• B. Straight line
• C. Spherical
• D. Helical✓

Explanation: Force is given by F = qvBsinθ, where F, q, v and B are the force, charge on particle, velocity of particle and magnetic field strength respectively. θ is the angle between v and B. If θ = 0 or 180, there is no force on the particle and it continues to move with uniform velocity. If θ = 90, the force acting on the particle is maximum and perpendicular to the path of the particle. (force acts as a centripetal force and the particle moves along a circular path) When θ has a value other than 0, 90 or 180, the direction of velocity is either perpendicular or parallel to B. If the component of velocity is parallel to B it will not be affected by the magnetic field. However if the component of velocity is perpendicular to B it will be subject to a force of the magnetic field which would result in uniform circular motion. Hence the particle would have a component along a straight line as well as a circular component. Therefore the path would be in the form of a helix. And so option D is correct.

Q178. When a charge experience a force, there will be a _ field developed.

• A. Magnetic
• B. Electric✓
• C. Static
• D. All of these options are correct

Explanation: A charged object creates an electric field - an alteration of the space or field in the region that surrounds it. Other charges in that field would feel the unusual alteration of the space. Whether a charged object enters that space or not, the electric field exists.

Q179. If electrons of charge ‘e’, with rest mass ‘m’, are accelerated through a potential difference ‘V’ and strike a metal target, then velocity of electrons is:

• A. Ve/m
• B. √(Ve/m)
• C. √(Ve)/2m
• D. √(2Ve/m)✓

Explanation: 1/2 𝑚𝑣2 = 𝑒𝑉Where ‘m’ is the rest mass of an electron and ‘v‘ is the velocity of the electron. ‘e’ is the charge on the electron in coulombs and ‘V’ is the potential difference by which the electron is accelerated. v2=2eV/m​ And hence velocity of the electron is: v=√(2Ve/m)

Q180. If the magnitude of charges on two point objects and the distance between them is doubled, then force will be:

• A. Two times
• B. Four times
• C. Unchanged✓
• D. Halved

Explanation: The explanation is as follows:

Q181. The speed of sound through a gas is measured as 340 m/s at pressure P1 and temperature T1. What will be the speed of sound if the pressure of a gas is doubled but the temperature is kept constant?

• A. 342 m/s
• B. 340 m/s✓
• C. 170 m/s
• D. 680 m/s

Explanation: According to laplace equation v=√(γP/p), the pressure and velocity are directly related however if the pressure is doubled then density would also double naturally, so the speed of sound would remain the same.

Q182. Two capacitors C1 (6μF) and C2(12μF) are in series across a 180 volts d.c. supply. Calculate the potential difference across each capacitor (C1 and C2).

• A. 98 volts ... 32 volts
• B. 120 volts ... 60 volts✓
• C. 68 volts ... 96 volts
• D. 30 volts ... 65 volts
• E. 25 volts ... 25 volts

Explanation: Since the voltage is INVERSELY proportional to the capacitance, according to the formula: Q=CV, the voltage division is also in the same way. Since the capacitance ratio is 1:2, the voltage division is 2:1. Hence the correct division of 180V voltage will be 120 V and 60V.

Q183. A body performing circular motion with a constant speed has a constant:

• A. momentum
• B. angular velocity✓
• C. acceleration
• D. radius vector

Explanation: A body moving along a circular path moves such that it traverses equal arc-length in equal intervals of time. Displacement, velocity and acceleration changes at each point on the trajectory. Hence, the speed is uniform and consequently the angular velocity is constant.

Q184. What is NOT true of 2 forces that give rise to a couple?

• A. They act in opposite directions
• B. They both act at the same point✓
• C. They both act on the same body
• D. They both have the same magnitude

Explanation: Two equal and opposite parallel forces not acting along the same line form a couple.

Q185. In case of harmonic oscillator total energy remains

• A. variable
• B. infinity
• C. constant✓
• D. zero

Explanation: During the oscillations, the total energy is constant and equal to the sum of the potential energy and the kinetic energy of the system, ETotal=12kx2+12mv2=12kA2. Hence total energy of the particle performing SHM is conserved.

Q186. Maximum power delivered by battery is

• A. Pmax= E^2/4r✓
• B. Pmax = 4rE^2
• C. Pmax = VIT
• D. Unlimited

Explanation: It states that the output power of a source of current is maximum, when the internal resistance of the source is equal to the external resistance in the circuit. So, if R is the external resistance of the circuit and r is the internal resistance of the source of current (i.e. a battery) then the output power is maximum, when R = r. This theorem is applicable to all types of source of e.m.f. and is related with the output power and NOT with the power dissipated. If E is the applied e.m.f. of the source of e.m.f. i.e. a battery of internal resistance r and R is the external resistance then current in the circuit is given as: I = E/(R + r) At the maximum output power, R = r, so we have: I = E/(r + r) = E/(2r) and maximum output power: Pmax = I2r = E2/(4r)

Q187. A bus and a car, moving at the same speed, are brought to rest by applying the same retarding force then:

• A. bus will come to rest in a shorter distance
• B. car will come to rest in a shorter distance✓
• C. both will come to rest in the same distance
• D. none of the above

Explanation: The distance they move will depend on their deceleration, which in turn would depend on the frictional force exerted by their respective brakes. If both were to experience the same frictional force 'F', then as per F=ma it is evident that the car having the lesser mass will decelerate faster ( greater magnitude of deceleration) and will therefore come to a halt sooner. Conceptually this is due to the effect of inertia as the bus has a greater mass of two vehicles.

Q188. Current carrying loop behaves like a

• A. monopole
• B. dipole✓
• C. quadrupole
• D. octupole

Explanation: The current carrying loop behaves like a dipole having two poles north and south.

Q189. The ionization power of _ ray is highest.

• A. Beta
• B. Gamma
• C. He-Ne laser
• D. None of these✓

Explanation: Among the three types of common radiation, alpha particles have the highest ionization power.Alpha particles are composed of two protons and two neutrons, and they have a positive charge. When they pass through matter, they interact strongly with the electrons and atoms of the material, causing a large number of ionizations. This means that they can knock off electrons from atoms, creating positively charged ions and free electrons, which can go on to create further ionizations.In comparison, beta and gamma radiation have lower ionization power.

Q190. Two wires of copper are of the same length but have different diameters. When they are connected in series across a battery, the heat generated is H1 When connected in parallel across the same battery, the heat generated during the same time is H2 Then:

• A. H1 = H2
• B. H1 < H2✓
• C. H1 > H2
• D. None of the above

Explanation: .

Q191. A handball is tossed vertically upward with a velocity of 19.6 m/s. Approximately how high will it rise?

• A. 15.8 m
• B. 19.6 m✓
• C. 25.6 m
• D. 30 m
• E. 60 m

Explanation: Working is attached below:

Q192. The half-life of C14 is about:

• A. 1637 years
• B. 892 years
• C. 10 years
• D. 100 years
• E. 5730 years✓

Explanation: Carbon-14 has a half-life of 5,730 ± 40 years—i.e. half the amount of the radioisotope present at any given time will undergo spontaneous disintegration during the succeeding 5,730 years.

Q193. Angular displacement is zero when:

• A. angle =0✓
• B. v=0
• C. r=0
• D. both b and c

Explanation: Arc length (s) is found by the formula = radius x angular displacement so angular displacement = arc length / radius and it can only be zero when the angle is zero.

Q194. Logical games: What should come next to save, secure, protect?

• A. Guard✓
• B. Lock
• C. Conserve
• D. Humble

Explanation: Save is a synonym of secure so to follow the pattern the answer needs to be a synonym of protect, which is guard.

Q195. Complete the series. F16, H32, J48, _.

• A. K66
• B. L64✓
• C. M68
• D. N90

Explanation: 16 is added every time to each term and the letters alternate. So after J, K will be skipped and 48+16 is 64 so the answer is L64.

Q196. If ‘-’ means ‘+’, ‘+’ means ‘-’, ‘*’ means ‘÷’ and ‘÷’ means ‘*’ then which of the following will be the correct equation?

• A. 10 + 5 - 14 ÷ 10 * 15 = 158
• B. 30 + 5 + 14 - 10 * 15 = 122
• C. 30 - 5 + 14 ÷ 10 * 15 = 162
• D. 30 * 5 - 4 ÷ 10 + 15 = 31✓
• E. None of these

Explanation: From option (d), 30 ÷ 5 + 4 * 10 - 15 = 6 + 40 - 15 = 46 - 15 = 31 Hence, option D is the correct answer.

Q197. Which one of the following has four sides

• A. Triangle
• B. Square✓
• C. Circle
• D. Right triangle

Explanation: A sides. A circle has no sides as A side requires two distinct endpoints joined by a straight line. For a circle, this will never be the case. A square has 4 corners hence it has 4 sides.

Q198. Statement: Without reforming the entire administrative system, we cannot eradicate corruption and prejudice from society. Assumptions: I. The existence of corruption and prejudice is good. II. There is enough flexibility to change the administrative system.

• A. Only assumption I is implicit
• B. Only assumption II is implicit✓
• C. Either I or II is implicit
• D. Both Options A and B are correct

Explanation: The statement talks of eradicating corruption and prejudice from society, which indicates that these aspects are undesirable. So, I am not implicit. Besides, the statement mentions reforming the administrative system. So II is implicit.

Q199. I. North Korea is protesting with South Korea for firing at their aircraft. II. South Korea Airforce is rightfully aiming for North Korean aircraft flying within the premises.

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

Explanation: After logically analyzing the given statements, we can deduce that Statement II is the cause whereas Statement I is its effect. North Korea can only protest after South Korea has fired at their aircraft.