Pk Mdcat Mock 4 — Solved Past Paper with Answers

Q1. Fill in the blank: Should I wear my joggers or my _?

• A. Cardigan
• B. Shorts
• C. Scarves
• D. Trainers✓

Explanation: Option D: The hint in the sentence is ‘joggers’ which is a footwear so the other part of sentence also requires a footwear ‘trainers’.

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

• A. Truth, goodness and beauty
• B. Property, outward success, luxury✓
• C. art and scientific research
• D. sense of fellowship with men of like mind
• E. preoccupation with the objective

Explanation: The writer mentions property, outward success, and luxury contemptible in lines 9 and 10(last two lines).

Q3. Pick the correct option:

• A. Seven students results are still awaited.
• B. Seven student’s results are still awaited.
• C. 'Seven students’ results are still awaited.✓
• D. Seven student results are still awaited.

Explanation: "Students’" is the correct possessive form of "students," showing that the results belong to multiple students. The apostrophe after "s" correctly indicates plural possession.

Q4. Identify the errors and choose the correct option:

• A. Guliver travels was written to Swift.
• B. Guliver travels was written at Swift.
• C. Guliver’s Travels was written by Swift.✓
• D. Gulivers’ Travel was written by Swift.

Explanation: Option A and Option B are incorrect since the apostrophe + ‘s’ (‘s) is absent which is needed after the noun “Gulliver” to indicate the possessive nature of the travels (i.e. to indicates that the travels were of Gulliver). Since Gulliver had more than one travel in the story, the word should be “Travels” and not “Travel”. Hence, Option D is incorrect, and Option C is correct.

Q5. Choose the correct option:

• A. “Well no, perhaps not sir”
• B. “Well, no, perhaps not sir”✓
• C. “Well, no perhaps not sir”
• D. “Well no perhaps, not sir”

Explanation: Commas should be used at these places to lay emphasis. The key to solving this question is to read the sentence in your head and then decide at which places a pause should be incorporated.

Q6. Read the passage and answer the following question:In earlier times, when every substance was believed to have its own qualities, there was no difficulty in believing that some substances were endowed with life, others not. Wood was wood, and water was water, and though transformations did occur, as in the disappearance of wood in the fire, they were not surprising in a world where the most miraculous changes were taking place under everyone’s every day. There was nothing but ‘doth suffer a sea-change into something rich and strange’. A seed put into the ground became in a short time a plant with leaves and flowers: the white and yolk of an egg turned into the flesh and bones and feathers of a chicken, which, no sooner was the shell cracked, jumped out and started running about. There was nothing but ‘Doth suffer a sea-change into something rich and strange’ means:

• A. The transformation of seed into a tree
• B. In everyday life natural things change drastically
• C. The suffering of change are always enormous
• D. Nature does not support any change
• E. Both A and B✓

Explanation: The term sea change is therefore often used to mean a marked change or metamorphosis or alteration, like a seed turning into a tree or yolk and white turning into a chick. Hence there are two answers to this question one by example(A) and the other by meaning(B).

Q7. The chess master promised to _ havoc upon his opponent’s pawn for taking his bishop.

• A. Endow
• B. Placate
• C. Ensue
• D. Warrant
• E. Wreak✓

Explanation: Wreak means to cause or inflict, often used in the context of damage, destruction, or harm. In this sentence, the chess master promises to cause havoc upon his opponent's pawn as a response to the pawn taking his bishop. This choice best captures the sense of the chess master taking aggressive action against the pawn. Therefore, option E is the correct answer.

Q8. How can this sentence be improved using punctuations?She hoped to find a new job. One that would let her earn money during the school year.

• A. job. One that
• B. job. The kind that
• C. job, one that✓
• D. job, so that it

Explanation: Since both the sentences are related to each other, a comma could be added. A comma marks a slight break between different parts of a sentence.

Q9. Read the passage and answer the question given at the end of the passage:Recent advances in science and technology have made it possible for geneticists to find out abnormalities in the unborn fetus and take remedial action to rectify some defects which would otherwise prove to be fatal to the child. Though genetic engineering is still at its infancy, scientists can now predict with greater accuracy a genetic disorder. It is not yet an exact science since they are not in a position to predict when exactly a genetic disorder will set in. While they have not yet been able to change the genetic order of the gene in germs, they are optimistic and are holding out that in the near future they might be successful in achieving this feat. However, genetic misinformation can sometimes be damaging for it may adversely affect people psychologically. Genetic information may lead to a tendency to brand some people as inferiors. Genetic information can therefore be abused and its application in deciding the sex of the fetus and its subsequent abortion is now hotly debated on ethical lines. But on this issue geneticists cannot be squarely blamed though this charge has often been leveled at them. It is mainly a societal problem. At present genetic engineering is a costly process of detecting disorders but scientists hope to reduce the costs when technology becomes more advanced. This is why much progress in this area is seen in scientifically advanced and rich countries like the U.S.A, UK and Japan. It remains to be seen if in the future this science will lead to the development of a race of supermen or will be able to obliterate disease from this world. Which of the following is the same in meaning as the phrase ' 'holding out" as used in the passage?

• A. Catching
• B. Expounding✓
• C. Sustaining
• D. Restraining

Explanation: Expounding can be defined as to explain by setting forth an argument. Although this doesn’t entirely fit into the given context, the remaining options can be readily eliminated.

Q10. Read the passage to answer the question:What is life? A little scum of no importance on the surface of an unimportant globe circling round a second-rate star? An accidental conglomeration of atoms which have come together by an odd chance, the result of an exceedingly improbable happening? That is what some astronomers would have us think. Looking out into the depth of space, they have discovered a universe of unthinkable dimensions. A billion suns in our own galaxy, beyond it perhaps a billion galaxies, only revealed to us as tiny smudges on a photographic plate. No wonder they are impressed by the enormous disparity between the scaffolding and the result. Life seemed to be, as Jeans said, ‘an utterly unimportant by-product’ in a universe which was clearly not designed for life, and which, to all appearances, is either totally indifferent or definitely hostile to it’. It seemed ‘incredible that the universe can have been designed primarily to produce life like our own; had it been so, surely we have might expected to find a a better proportion between the magnitude of the mechanism and the amount of the product. According to the author if the universe had been designed primarily to produce life like our own then:

• A. there would have been a smaller proportion for us
• B. there would have been a better proportion for us✓
• C. there would have been more luxuries in the universe
• D. there would have be many galaxies containing many creatures
• E. there would have been many new stars and earths

Explanation: The author demeans the idea that the universe is primarily designed to produce life, supporting it by the fact that there is so little life in-universe as mentioned in lines below: “It seemed ‘incredible that the universe can have been designed primarily to produce life-like our own; had it been so, surely we have might be expected to find a better proportion”

Q11. Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters.ENFEEBLED:

• A. Distanced
• B. Dominant
• C. Mistaken
• D. Powerful✓

Explanation: Enfeebled means someone lacking physical strength and being weak. Powerful is the direct opposite of this word.

Q12. 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.

Q13. Television is typical of many new scientific words which are deliberately invented from old Greek and Latin words. In this case, the prefix ‘tele’ is Greek and means ‘far’ (of telephone, telegram), while the root ‘vision’ is derived from the Latin verb meaning ‘to see’.The word “Television” is invented from:

• A. English and Spanish
• B. French and Arabic
• C. Dutch and German
• D. Greek and Latin✓

Explanation: It can be directly inferred from the passage that television is invented from old Greek and Latin words. This is clearly mentioned in Lines 1 and 2.

Q14. Choose the correct sentence.

• A. It is my birthday in june I would like a book by Charles Dickens.
• B. It is my birthday in June. I would like a book by Charles Dickens.✓
• C. It is my birthday in June; I would like a book by Charles Dickens.
• D. It is my birthday in June. I would like a book by Charles Dickens!

Explanation: Option B displays correct use of capitalization and punctuation.

Q15. Select the word or phrase which is closest in meaning to the underlined word.Due to his continuous mischievous activities, he has become a rogue person.

• A. Thief
• B. Honest
• C. Dishonest✓
• D. Sharp

Explanation: Rogue is a person who is dishonest and unreliable.Dishonest is the one who is a fraud and unreliable. So, dishonest is the suitable answer.

Q16. The word opposite in meaning to capacious is:

• A. Voluminous
• B. Commodious
• C. Large
• D. Restricted✓

Explanation: Restricted means limited. Hence, restricted is the closest antonym.

Q17. Complete the sentence by choosing the most appropriate option, from the given lettered choices (A to E) below:It is quite _ for poor people to be happier than rich people.

• A. Possible✓
• B. Risky
• C. Potential
• D. Liable
• E. Different

Explanation: The best option is "possible", as it expresses the idea that it is indeed possible for poor people to be happier than rich people.

Q18. In each of the following question, four alternative meanings of a word are given. You have to select the NEAREST CORRECT MEANING of the given word and fill the appropriate Circle on the MCQ Response Form.NEOLOGISM

• A. A new word✓
• B. Pleasant remark
• C. Brief summary
• D. Archaic expression

Explanation: Explanation:A new word refers to a recently created or invented word, or a word that has taken on a new meaning over time. So, A is the correct answer. This option does not relate to the meaning of "neologism". This option also does not relate to the meaning of "neologism". This option also does not relate to the meaning of "neologism".

Q19. _ alleles both have an effect on the phenotype of a heterozygous organism:

• A. Dominant
• B. Recessive
• C. Co-dominant✓
• D. Multiple

Explanation: In a Co-dominant scenario, the two different alleles of the gene contributing to a particular characteristic would express themselves in a collaborative manner, producing a phenotype that is a combination of the two different phenotypes coded by the respective alleles.

Q20. Which of the following organelles are present in all the bacteria?

• A. Mesosome
• B. Ribosomes✓
• C. Golgi bodies
• D. Mitochondria

Explanation: The correct answer is 'Ribosomes.' In bacteria, which are prokaryotic organisms, ribosomes are present and essential for protein synthesis. These are not membrane-bound and are found throughout the cytoplasm. Other options such as Golgi bodies, mitochondria, and chloroplasts are membrane-bound organelles found in eukaryotic cells, not in bacteria. Mesosomes were once thought to be a common organelle in bacteria, but they are now largely considered artifacts of cell preparation.

Q21. The following flowchart depicts the steps of the Calvin Cycle. Which option, according to you, fits in as the correct answer to the missing step?

• A. Pyruvate
• B. Hydrogenase
• C. Ribulose bisphosphate✓
• D. Oxaloacetate

Explanation: The first step involves the fixing of carbon (derived from CO2) into molecules of Ribulose Bisphosphate (RuBP) via the action of the enzyme 'rubisco', resulting in the formation of 3-phosphoglycerate. This is further processed into 1,3-BPG and eventually, G-3-P, before the cycle starts again. The chart above only has RuBP missing.

Q22. Female rabbits are:

• A. Induced ovulators✓
• B. Spontaneous ovulators
• C. Seasonal ovulators
• D. Indifferent ovulators

Explanation: This is the following solution:

Q23. Which of the following strategies of enzymatic inhibition is used by noncompetitive inhibitors?

• A. Bind to substrate so that it cannot bind to the active site
• B. Target the enzyme for destruction using a protease
• C. Bind to the active site and prevent substrate from binding
• D. Bind to an allosteric site to cause a conformational shift in the enzyme✓

Explanation: . Option D is correct since non-competitive inhibitors bind to a site on the enzyme away from the active site, called the allosteric site. The non-competitive inhibitors do not compete with the substrate for occupancy of the active site. The binding of the non-competitive inhibitor to the allosteric site brings about either a temporary or a permanent change in the shape of the active site Option A is incorrect since the inhibitors (both competitive and non-competitive) do not bind with the substrate. They bind with the enzyme. Option B is incorrect since the non-competitive inhibitor does not target the enzyme for destruction by a protease Option C is incorrect since it states the property of a competitive inhibitor

Q24. Estimating relative CO2 consumption or O2 release during photosynthesis at different wavelengths of light, is termed as:

• A. Action spectrum✓
• B. Absorption spectrum
• C. Dark reaction
• D. Light reaction

Explanation: An action spectrum is a graph of the rate of biological effectiveness plotted against the wavelength of light. It shows which wavelength of light is most effectively used in specific chemical reactions. Some reactants are able to use specific wavelengths of light more effectively to complete their reactions.An absorption spectrum defines the spectrum of electromagnetic radiation, or light, plants absorb.

Q25. Identify the wrong statements.(a) The substrate binds to active site of enzyme and does not fit into active site(b) The binding of substrate induces the enzyme to alter its shape(c) Chemical bonds of substrate break down not to form new enzyme-product complex(d) The enzyme releases the products of the reaction and runs through catalytic cycle once again

• A. A, C✓
• B. B, D
• C. B, C
• D. A, D

Explanation: The question asks to identify the wrong statements regarding enzyme function.1. Statement A is incorrect because the substrate indeed fits into the active site of the enzyme, as they are specifically designed to complement each other.2. Statement B is correct, as the binding of a substrate does induce a change in the enzyme's shape, enhancing the fit between them.3. Statement C is incorrect; when the substrate binds, it forms an enzyme-substrate complex before the chemical bonds are broken, leading to product formation.4. Statement D is correct because after the reaction occurs, the enzyme releases the products and can catalyze another reaction by binding to a new substrate.Thus, the correct answer is option A, as it includes the incorrect statements A and C, while the other options contain at least one correct statement.

Q26. Read the passage below to answer the question: Hemophilia is a disorder in which blood fails to clot. Saad, a male hemophiliac, marries Sara, a normal woman and together they have four children, two boys (Ahmed and Ali) and two girls (Alia and Ayesha). None of the children display the symptoms of Hemophilia. Ahmed, Ali, Ayesha, and Ali all marry normal individuals and have children. None of Ahmed's or Ali’s children, male or female, display symptoms of hemophilia, but the sons of Alia and Ayesha display symptoms of hemophilia while the daughters of Alia and Ayesha do not. If one of Ali's daughters marries a normal man, what is the probability that one of their children will display symptoms of hemophilia:

• A. 0%✓
• B. 25%
• C. 50%
• D. 75%
• E. 100%

Explanation: Ali and Ahmed are normal males because they receive a Y chromosome from their father and Haemophilia is an X-linked disorder. Ali marries a normal female and will therefore have a normal daughter. If this normal daughter marries a normal male, the probability that they will have haemophiliac children is 0%.

Q27. The stomata are closed at which of the following temperature? (in ˚C)

• A. 45✓
• B. 35
• C. 15
• D. 25

Explanation: Option A is correct since stomata are closed at temperatures greater than 35˚C. Option B is incorrect since at 35˚C some plants may close their stomata and some may not. Option C is incorrect since, at 15˚C, the stomata of a plant are open. Option D is incorrect since, at 25˚C, the stomata of a plant are open.

Q28. Select the correct statement regarding the specific disorder of the muscular or skeletal system.

• A. Muscular dystrophy – A genetic disorder leading to progressive muscle weakness and degeneration
• B. Osteoporosis – A condition characterized by reduced bone density, making bones fragile and more prone to fractures
• C. Myasthenia gravis – An autoimmune disorder resulting in muscle weakness due to impaired communication between nerves and muscles
• D. Gout – A form of arthritis characterized by sudden, severe attacks of pain and swelling in the joints due to uric acid crystallization
• E. All of these are correct✓

Explanation: All of the options are correct as they are related to the reason and the disease name.

Q29. Which of the following is correct for the given structure?

• A. These are small structures which work like oars
• B. It is covered with plasma membrane
• C. It's core is called axoneme
• D. All of the above✓

Explanation: Cilia and flagella are hair-like outgrowths of the cell membrane. Cilia are small structures working like oars, causing the movement of either the cell or the surrounding fluid. Flagella, in comparison, is longer and is responsible for cell movement. Both cilium and flagellum are covered with plasma membrane. Their core, called axoneme, possesses a number of microtubules running parallel to the long axis.So, the correct answer is 'All of the above'.

Q30. Four events in the transmission of nerve impulses across synapses are:I. Depolarisation of the presynaptic membraneII. Propagation of postsynaptic action potentialIII. Reabsorption of the transmitter substanceIV. Release of transmitter substance into the synaptic cleftIn which sequence do these events occur?FIRST -> LAST

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

Explanation: The sequence of transmission of nerve impulses is as follows:1. Depolarisation occurs at the presynaptic terminal.2. This leads to the release of the transmitter substance to the cleft.3. This leads to the depolarization at the postsynaptic membrane.4. Then the transmitter substance is reabsorbed back to the presynaptic membrane.So, from the above summary, it shows that the sequence in the transmission of nerve impulses across synapses is 1, 4, 2, and then 3.

Q31. A person with blood group A will not produce:

• A. None of these
• B. Anti-A antibodies✓
• C. Anti-B antibodies
• D. Both anti-A and anti-B antibodies

Explanation: A person with blood group A will have A antigens on his RBCs but anti-B antibodies in his blood plasma. Similarly, a person with blood group O will have no antigens on his RBCs but anti-A and anti-B antibodies in his blood plasma. A person with blood group A cannot have anti-A antibodies.

Q32. Referring to sexual reproduction, humans are:

• A. Hermaphrodites
• B. Vivaparous✓
• C. Oviparous
• D. Self-fertilized

Explanation: The main difference between oviparous and viviparous animals is that oviparous animals do not undergo any embryonic development inside the mother whereas viviparous animals develop into young animals inside the mother. This means oviparous animals lay eggs. These eggs develop and hatch into young individuals.A hermaphrodite is an organism with both male and female genitalia. In sexually reproducing organisms, males have organs that produce male gametes, usually sperm. Sometimes the genders pair off equally, one male for one female. Other times, one male or female will breed with a large group of the other gender.

Q33. What is true for pili and flagella-like structures of bacteria?

• A. Both are same in size
• B. Both help in movement
• C. Both are composed of proteins✓
• D. All of the above options are correct

Explanation: Option A: This is not the correct option because pili are smaller than flagella.Option B: Flagella help in locomotion while pili are used in conjugation therefore this is not the correct option.Option C: This is the correct option. Flagella are made up of a protein called flagellin whereas pili are made of a protein called pilin.Option D: Option A and B are incorrect therefore this cannot be the correct option.

Q34. There are 3 stages of HIV infection, which sequence is correct

• A. AIDS, Chronic HIV, Acute HIV
• B. Chronic HIV, AIDS, Acute HIV
• C. Acute HIV, Chronic HIV, AIDS✓
• D. all of them

Explanation: In stage one, People have a large amount of HIV in their blood. They are very contagious. Some people have flu-like symptoms. This is the body’s natural response to infection. But some people may not feel sick right away or at all. If you have flu-like symptoms and think you may have been exposed to HIV, seek medical care and ask for a test to diagnose acute infection. In stage 2, This stage is also called asymptomatic HIV infection or clinical latency. HIV is still active but reproduces at very low levels. People may not have any symptoms or get sick during this phase. Without taking HIV medicine, this period may last a decade or longer, but some may progress faster. People can transmit HIV in this phase. At the end of this phase, the amount of HIV in the blood (called viral load) goes up and the CD4 cell count goes down. The person may have symptoms as the virus levels increase in the body, and the person moves into Stage 3. People who take HIV medicine as prescribed may never move into Stage 3. In the third stage, The most severe phase of HIV infection. People with AIDS have such badly damaged immune systems that they get an increasing number of severe illnesses, called opportunistic infections. People receive an AIDS diagnosis when their CD4 cell count drops below 200 cells/mm, or if they develop certain opportunistic infections. People with AIDS can have a high viral load and be very infectious. Without treatment, people with AIDS typically survive about three years.

Q35. Sarcoplasmic reticulum is like endoplasmic reticulum but devoid of _ and exhibit a highly specialized _ pattern.

• A. Ribosome, repeating✓
• B. Mitochondrion, repeating
• C. Ribosome, simplified
• D. Mitochondrion, simplified
• E. Ribosome, zig zag

Explanation: The sarcoplasmic reticulum is a specialized type of endoplasmic reticulum found in muscle cells. It is responsible for storing and releasing calcium ions necessary for muscle contraction. The sarcoplasmic reticulum is similar to the endoplasmic reticulum in structure but lacks ribosomes (hence the answer A). The pattern of the sarcoplasmic reticulum is highly specialized and repeating, which allows for the efficient release of calcium ions during muscle contraction.

Q36. The sequence of amino acids in a polypeptide chain corresponds to the sequence of nucleotides on mRNA. If the reading frame of mRNA for a human protein is 993 nucleotides including a stop codon, how many amino acids would be incorporated?

• A. 331
• B. 993
• C. 93
• D. 330✓

Explanation: Each codon = 3 nucleotides → 993 ÷ 3 = 331 codons. One is a stop codon → 330 codons code for amino acids.

Q37. Amoeboid movements and movement of cyclosis is due to?

• A. Microfilaments✓
• B. Microtubules
• C. Intermediate filaments
• D. Cytoskeleton

Explanation: Microfilaments, also known as actin filaments, play a pivotal role in amoeboid movements and cyclosis due to their ability to rapidly assemble and disassemble, allowing cells to change shape and move. Microtubules, while important for structural support and intracellular transport, do not directly contribute to these specific types of movement. Intermediate filaments primarily provide tensile strength to cells and are not involved in mobility. The cytoskeleton encompasses all these components, but it is the microfilaments that directly mediate the dynamic processes of movement.

Q38. The diagram shows a section through the human brain.

• A. The Thalamus is responsible for motor control
• B. The Cerebellum coordinates voluntary movements✓
• C. The medulla oblongata processes visual information
• D. The Thalamus regulates breathing and heart rate
• E. The cerebellum processes auditory information

Explanation: The correct answer is Option B: The cerebellum coordinates voluntary movements. It is crucial for maintaining balance and posture, as well as fine-tuning motor activities. The thalamus (Option A and D) primarily serves as a relay station for sensory information and does not directly control motor actions or autonomic functions like breathing and heart rate. The medulla oblongata (Option C) is responsible for autonomic functions such as heart rate and breathing, but not for processing visual information. Option E is incorrect because the cerebellum is involved in coordinating movements, not processing auditory information, which is handled by the cerebral cortex, specifically the temporal lobe.

Q39. A person was married to his cousin and both are heterozygous for Sickle Cell anemia. Among their four kids, what will be the proportion of homozygotes?

• A. 75%
• B. 50%✓
• C. 100%
• D. 25%

Explanation: When both parents are heterozygous for sickle cell anemia (HbN HbS), a Punnett square reveals the possible genotypes of their offspring: 25% will be homozygous normal (HbN HbN), 50% will be heterozygous (HbN HbS), and 25% will have sickle cell anemia (HbS HbS). Therefore, 50% of the offspring will be homozygous, as 25% are homozygous normal and 25% have sickle cell anemia. Option B is correct. Options A and C overestimate the proportion of homozygotes, while option D underestimates it by considering only one type of homozygous condition.

Q40. Stretch receptors are present in the _ of tetrapods.

• A. Hepatic arteries
• B. Carotid arteries✓
• C. Renal arteries
• D. Pulmonary arteries

Explanation: Stretch receptors are found around the carotid artery, where they monitor blood pressure and stimulate the release of antidiuretic hormone (ADH) from the posterior pituitary gland.

Q41. A family of five daughters is expecting another delivery. The chance of its beings a son is?

• A. Zero
• B. 25%
• C. 50%✓
• D. 100%

Explanation: The chances of a baby being either boy or girl are always 50% because in human beings there are 22 pairs of autosomes and one pair of sex chromosomes. The female is homozygous while the male is heterozygous and genetically responsible for the sex of the child. Sperms are of two types, i.e. sperms have an X-chromosome which leads to a girl being born, and sperms have a Y-chromosome which is responsible for a boy being born. So, the correct answer is '50%'.

Q42. A child with AB blood group who was born to a mother of the genotype IAIA cannot have the father of the genotype:

• A. IA IA✓
• B. IB IB
• C. IB IO
• D. IB IB and IB IO

Explanation: A is the correct option because the genotype of the mother is IA IA. A child with blood group AB will have a genotype IA IB. This genotype of the child is possible in 2 cases either if the genotype of the father is IB IB or IB IO. However a genotype IA IA of the father will not result in the AB blood group of the child. Thus the correct answer is option A.

Q43. Diaphragm is a sheet of:

• A. Smooth muscles
• B. Cardiac muscles
• C. Skeletal muscles✓
• D. All of these

Explanation: The floor of the chest is called diaphragm which is a sheet of skeletal muscles. Diaphragm contracts during inhalation and expands during exhalation.

Q44. It is the most energy rich compound:

• A. FADH2
• B. ATP✓
• C. NADH
• D. GTP

Explanation: ATP is indeed the most energy-rich compound in cellular metabolism. ATP (adenosine triphosphate) is the cell's primary energy currency. It stores and transfers energy for various cellular processes. The energy stored in ATP is primarily in the form of the high-energy phosphate bonds between its three phosphate groups. When ATP is hydrolyzed by the enzyme ATPase, it undergoes a reaction in which one of the phosphate groups is cleaved, forming adenosine diphosphate (ADP) and inorganic phosphate (Pi). This hydrolysis reaction releases a significant amount of energy that can be utilized by cells to perform work. The energy released from the hydrolysis of ATP powers a wide range of cellular processes, including muscle contraction, active transport of molecules across membranes, synthesis of macromolecules, nerve signal transmission, and many other energy-requiring reactions in cells.

Q45. The venous blood in tissues has carbon dioxide:

• A. 19.6 ml/100 ml of blood
• B. 50 ml/100 ml of blood
• C. 54 ml/100 ml of blood✓
• D. 96 ml/100 ml of blood

Explanation: The venous blood in tissues has 54 ml carbondioxide/100 ml of blood.

Q46. In which organism males are haploid?

• A. Aphids
• B. Mosquito
• C. Butterfly
• D. Honey bee✓

Explanation: The only organism in the list that has haploid males is the honeybee. This is because honeybees have a unique sex determination system called haplodiploidy. In haplodiploidy, the sex of an offspring is determined by the number of sets of chromosomes that the offspring inherits from its mother. If the offspring inherits a single set of chromosomes from its mother, it will be male. If the offspring inherits two sets of chromosomes from its mother, it will be female.

Q47. Which of the following is a hypnotic drug?

• A. Luminal✓
• B. Salol
• C. Catechol
• D. Phenol
• E. All of these

Explanation: Luminal is the trade name for phenobarbital, a barbiturate drug. Barbiturates are central nervous system depressants that are used as sedatives or hypnotics (sleep-inducing agents). The other substances are simple phenols used as antiseptics. 22. Answer : B

Q48. Calcium, during muscle contraction, binds with?

• A. Tropomyosin
• B. Troponin C✓
• C. Troponin I
• D. Troponin T

Explanation: The correct option is B. Calcium is released from the sarcoplasmic reticulum through calcium ion channels when the membrane of the T-tubular system is excited. It binds to Troponin C, causing it to conform, hence permitting the myosin head to latch onto the actin filament, initiating muscle contraction.

Q49. E. coli is

• A. Anaerobic
• B. Gram negative
• C. Facultative
• D. All of the above✓

Explanation: E coli is a gram negative (Stains pink with Gram's stain), facultative and anaerobic microbe.

Q50. Taxonomy includes the arrangement of organisms into different taxa. Which of the following represents the correct hierarchy of various taxa of classification?

• A. Species, genus, family, order, class, phylum✓
• B. Order, family, class, phylum, kingdom
• C. Species, genus, family, class, order, phylum
• D. Species, genus, order, family, class, phylum

Explanation: The correct hierarchy of various taxa in biological classification is:Species, genus, family, order, class, phylumExplanation:1. Species: The fundamental unit of classification, consisting of organisms that can interbreed and produce fertile offspring.2. Genus: A group of closely related species.3. Family: A group of related genera.4. Order: A group of related families.5. Class: A group of related orders.6. Phylum: A group of related classes.This hierarchical arrangement helps organize and categorize living organisms based on their evolutionary relationships.Mnemonics, that one can use to memorize the taxonomic hierarchy, which is Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species, in that specific order are as follows:-“Dear King Philip Came Over For Good Soup" (the first letter of each word corresponds to a taxa)- Kingdom Phylum went to a Class and Ordered his Family to look for a Genius(Genus) who is a rare Species.The diagram, given below, illustrates the hierarchy.

Q51. In eggs, Ca+2 plays an important role especially at the time of fertilization. Therefore _ are present in many thousand numbers inside the cell membrane.

• A. Ribosomes
• B. Chloroplast
• C. Mitochondria
• D. Endoplasmic Reticulum✓

Explanation: The Endoplasmic Reticulum (ER) serves as a major reservoir of calcium ions (Ca2+) in cells. During fertilization, there is a need for precise regulation and release of Ca2+, which the ER facilitates. Ribosomes, while essential for protein synthesis, do not store calcium. Chloroplasts are irrelevant in animal cells, and mitochondria, though involved in calcium signaling, do not primarily store Ca2+ like the ER does.

Q52. Which two reactions occur during photophosphorylation.

• A. ATP is hydrolysed and NADP is reduced
• B. ATP is hydrolysed and NADPH is oxidized
• C. ATP is synthesized and NADP is reduced✓
• D. ATP is synthesized and NADPH is oxidized

Explanation: During photophosphorylation, which is part of the light-dependent reactions of photosynthesis, ATP is synthesized through a process known as chemiosmosis. Concurrently, NADP is reduced to NADPH by gaining electrons and protons. This process is crucial for converting light energy into chemical energy stored in ATP and NADPH, which are then used in the Calvin cycle. The incorrect options either mention the hydrolysis of ATP, which does not occur in photophosphorylation, or the oxidation of NADPH, which is incorrect as NADPH is the reduced form.

Q53. Which one of the following is present outside the plasma membrane but inside the cell wall?

• A. Sphaerosome
• B. Peroxisome
• C. Lomasome✓
• D. Golgi body

Explanation: 'Lomasomes' are present outside the plasma membrane but inside the cell wall. They are membranous structures, often containing internal membranes, located between the plasma membrane and cell wall of plant cells. Lomasomes appear to be accumulations of ejected material, between the plasmalemma and cell wall that has become sequestered by the deposition of wall material. Thus, the correct answer is option 'C'.

Q54. Which of the following statements is true about ATP?

• A. ATP is a coenzyme✓
• B. ATP is the prosthetic part of an enzyme
• C. ATP is the organic portion of an enzyme
• D. ATP is an enzyme

Explanation: Adenosine Triphosphate (ATP) is a well-known non-vitamin coenzyme that transfers phosphate groups during reactions. It is also known as the cellular currency of energy. It also transports substances and energy required during reactions.

Q55. An example of competitive inhibition of an enzyme is the inhibition of:

• A. Succinic dehydrogenase by malonic acid✓
• B. Cytochrome oxidase by cyanide
• C. Hexokinase by glucose
• D. Carbonic anhydrase by carbon dioxide

Explanation: The inhibition of succinic dehydrogenase by malonic acid is an example of competitive inhibition. Succinic dehydrogenase is an enzyme involved in the citric acid cycle (also known as the Krebs cycle) and plays a role in the conversion of succinate to fumarate. Malonic acid serves as a competitive inhibitor in this context. It structurally resembles the substrate (succinate) and competes with it for binding to the active site of succinic dehydrogenase. Malonic acid binds to the active site of the enzyme, preventing the normal substrate (succinate) from binding and undergoing the catalytic reaction. The presence of malonic acid decreases the rate of the succinic dehydrogenase-catalyzed reaction by interfering with the binding of succinate.

Q56. _ refers to the breakdown or removal of the capsid.

• A. Assembly
• B. Uncoating✓
• C. Integration
• D. Maturation

Explanation: Option A: Assembly—The stage where viral genomes and structural proteins come together inside the host cell to form new virions.Option B: Uncoating—The step where the viral capsid is disassembled after entry, releasing the viral genome into the host cell. Triggered by receptor signals, enzymes, or pH changes.Option C: Integration—The process in which certain viruses (e.g., retroviruses) insert their genome into the host’s DNA, allowing long-term persistence.Option D: Maturation—Final modifications of virions to become infectious, often involving proteolytic cleavage or envelope acquisition.

Q57. The area on the left hemisphere related to speech is called?

• A. Amygdala
• B. Broca's area✓
• C. Hypothalamus
• D. Occipital lobe

Explanation: Option A: The amygdala is commonly thought to form the core of a neural system for processing fearful and threatening stimuli (4), including detection of threat and activation of appropriate fear-related behaviors in response to threatening or dangerous stimuli. Option B: Broca’s area is also known as the motor speech area. It is near the motor cortex and utilized in speech production, located in the inferior frontal gyrus. This area regulates breathing patterns while speaking and vocalizations required for normal speech. Option C: The Hypothalamus is a structure deep in your brain, acts as your body's smart control coordinating center. Its main function is to keep your body in a stable state called homeostasis. It does its job by directly influencing your autonomic nervous system or by managing hormones. Option D: The occipital lobes sit at the back of the head and are responsible for visual perception, including colour, form, and motion. Damage to the occipital lobe can include: Difficulty with locating objects in the environment

Q58. Which disorder among the following CANNOT be detected by amniocentesis?

• A. Haemophilia
• B. Heart defects✓
• C. Tay-Sachs disease
• D. Cystic fibrosis

Explanation: This question is simply choosing the odd one out. Heart defects are not genetic.Amniocentesis is used to detect genetic defects like those mentioned in other options.

Q59. Nuclear Histones are conjugated molecules that function in _.

• A. RNA coiling
• B. Gene expression✓
• C. DNA formation
• D. Protein synthesis

Explanation: Histones are involved in gene expression, as they play a role in regulating the accessibility of DNA to the transcriptional machinery.

Q60. Ptyalin can convert starch into:

• A. Monosaccharide form
• B. Oligosaccharide form✓
• C. Polysaccharide form
• D. All given options

Explanation: Amylase is found in saliva and breaks starch into maltose and dextrin, an oligosaccharide.

Q61. What are the distinguishing features of fibrous proteins?

• A. Elastic
• B. Non-crystalline
• C. Disorganized
• D. Both A and B✓

Explanation: The distinguishing features of fibrous proteins include their elasticity and non-crystalline nature. Elasticity is exemplified by proteins like elastin, which allows tissues to stretch and return to their original form. They do not form crystalline structures but instead have elongated, filamentous shapes. The option Both A and B is correct because it encompasses both these characteristics. The option Elastic alone is incomplete without acknowledging the non-crystalline aspect. Similarly, Non-crystalline alone does not capture the functional aspect of elasticity. Disorganized is incorrect as fibrous proteins have a highly ordered structure, unlike what the term suggests.

Q62. Carotenoids perform protective function in which of the following organism?

• A. Animals
• B. Plants
• C. Both✓
• D. None of these

Explanation: Carotenoids are important pigments found in both plants and animals. In plants, they act as antioxidants and pigments, protecting cells from light-induced damage and oxidative stress. In animals, they play a role in protecting the eyes and skin from UV light and oxidative damage. Therefore, the correct answer is Option C: Both. Options A and B are incorrect because they limit the protective function of carotenoids to either animals or plants only, whereas Option D is incorrect because it states that carotenoids do not have a protective role in any organisms, which is not true.

Q63. What is critical in photoperiodism?

• A. Length of light period
• B. Length of dark period✓
• C. Both Options A and B are correct
• D. None of these options is correct

Explanation: Both the length of the light period and the length of the dark period play important roles in photoperiodism. But, only length of dark period is critical in photoperiodism, because if plants are grown according to their short or long priods but only if their length of dark period is interrupted by a small period of light then their flowering is prevented.

Q64. Male and female sea urchins release their sperm and eggs Into the water where fertilization takes place. How can their reproduction be described?

• A. Asexual reproduction which results in genetically dissimilar offspring
• B. Asexual reproductlon whlch results In genetically identical offspring
• C. Sexual reproduction which results in genetically dissimilar offspring✓
• D. Sexual reproduction which results in genetically identical offspring

Explanation: A type of reproduction in which gametes join to form a new offspring is called sexual reproduction. Sexual reproduction involves the mixing of two genetic materials resulting in genetically dissimilar offspring.

Q65. Whenever a muscle contracts, a sarcomere can be shortened up to _ % of its total length.

• A. 15
• B. 25
• C. 35✓
• D. 45

Explanation: The correct answer is 35%. During a maximal muscle contraction, the sarcomere shortens by about 35% of its original length. This is because the actin and myosin filaments slide past each other, reducing the length of the sarcomere. Options 15% and 25% underestimate the typical shortening that occurs, while 45% overestimates it, making 35% the most accurate representation of sarcomere shortening during contraction.

Q66. Monosynaptic reflex arc consists of:

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

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

Q67. In a typical compound microscope the resolution is 2 μm. Which is about _ that of naked eye.

• A. 100 x
• B. 300 x
• C. 400 x
• D. 500 x✓

Explanation: Resolution is the measurement of the number of pixelsNaked eye resolution is 576 Megapixels which is 500 times the resolution of compound microscopeThe resolution of the naked eye refers to its ability to distinguish and perceive fine details or distinguish between two closely spaced objects. The resolution of the human eye is limited by several factors, including the number of photoreceptor cells in the retina and the optics of the eye.On average, the human eye can resolve objects that are approximately 1 arcminute apart. This means that if two objects are separated by an angle of 1 arcminute (which is 1/60th of a degree), a person with normal vision would be able to perceive them as separate entities rather than a single object.

Q68. α(1-4) glycosidic linkage is present in

• A. Maltose✓
• B. Sucrose
• C. Cellulose
• D. Cellobiose

Explanation: Maltose is the correct answer because it is formed by two D-glucose molecules connected through an α(1-4) glycosidic bond. This is a characteristic feature of maltose.Sucrose, on the other hand, is a disaccharide consisting of glucose and fructose linked by an α(1-2) bond, which does not match the linkage type in the question. Cellulose is a polysaccharide composed of glucose units connected by β(1-4) linkages, and cellobiose is a disaccharide formed from two glucose units with a β(1-4) linkage, both differing from the α(1-4) linkage required.

Q69. Proteoglycan in cartilages (which consists of polysaccharides) are also attached to:

• A. Chondroitin✓
• B. Ossein
• C. Casein
• D. Cartilagin
• E. None

Explanation: Proteoglycans consist of polysaccharides attached with protein chondroitin. It is present in cartilage as well as in extracellular material. Ossein is a protein present in the matrix of bone. Casein is a milk protein.

Q70. Vertebrae of the neck are called:

• A. Coccygeal vertebrae
• B. Cervical vertebrae✓
• C. Sacral vertebrae
• D. Lumbar vertebrae

Explanation: In tetrapods, 'cervical vertebrae' (singular: vertebra) are the vertebrae of the neck, immediately below the skull. Truncal vertebrae (divided into thoracic and lumbar vertebrae in mammals) lie caudal (toward the tail) of cervical vertebrae.

Q71. The hormone labeled X in the diagram is:

• A. Estrogen
• B. Progesterone
• C. FSH
• D. LH✓
• E. Testosterone

Explanation: Hormone X is LH because at 14th day of menstrual cycle, LH has highest peak which causes ovulation and stimulate ovaries to produce progesterone.

Q72. Hepatic and pancreatic secretions are also stimulated by a hormone called:

• A. Gastrin
• B. Secretin✓
• C. HCl
• D. Enterokinase

Explanation: Secretin is the correct answer because it is a hormone released by the small intestine in response to acidic chyme. It stimulates the pancreas to secrete bicarbonate, which neutralizes stomach acid and promotes liver bile production, thus facilitating digestion. In contrast, gastrin primarily stimulates the stomach's activity; HCl is a gastric secretion rather than a hormone, and enterokinase is an enzyme that activates other digestive enzymes but does not stimulate secretion from the liver or pancreas.

Q73. The inflammation of bronchi or bronchioles is known as:

• A. Emphysema
• B. Asthma
• C. Pneumonia
• D. Bronchitis✓

Explanation: Bronchitis is a respiratory illness that causes inflammation of the bronchioles, which are the small airways in the lungs. It is most commonly caused by a viral infection, such as respiratory syncytial virus (RSV), and is most common in infants and young children. The inflammation of the bronchioles can cause wheezing, coughing, shortness of breath, and difficulty breathing, which can be severe in some cases. Bronchiolitis can be diagnosed based on the symptoms and a physical exam, and may be confirmed with a chest X-ray or other tests. Treatment for bronchiolitis typically involves supportive care, such as fluids, humidified air, and medications to relieve symptoms. In some cases, hospitalization may be necessary, especially for infants and young children who are at higher risk of complications. So option D is correct.

Q74. Hexokinase is used in:

• A. Calvin Cycle
• B. Glycolysis✓
• C. Kreb's Cycle
• D. None of these

Explanation: Hexokinase is an enzyme used in the phosphorylation of glucose during the first step of glycolysis. This enzyme catalyzes the conversion of glucose to glucose-6-phosphate. The reaction involves the transfer of a phosphate group from ATP to glucose, resulting in the formation of glucose-6-phosphate.

Q75. Antibodies can be digested by using which of the following types of enzymes?

• A. Lipase
• B. Protease✓
• C. Amylase
• D. Polymerase

Explanation: Antibodies, being proteins, can be digested or broken down by proteolytic enzymes. Proteolytic enzymes, also known as proteases or peptidases, specifically cleave peptide bonds in proteins, leading to their degradation.

Q76. The characteristics and an example of a synovial joint in humans is:

• A. Characteristics - Cartilage between two bones, allows limited movements, Examples - Knee joint
• B. Characteristics - Fluid-filled cavity between two bones, reduces friction, Examples - Joint between coxal bones
• C. Characteristics - Fluid-filled space between two bones, provides cushioning, Examples - Skull bones
• D. Characteristics - Synovial fluid-filled cavity, allows gliding movements, Examples - Gliding joint between carpals✓

Explanation: Synovial joints are characterized by the presence of a synovial cavity filled with synovial fluid, which acts as a lubricant and reduces friction during movement. Option D accurately highlights these features and provides a correct example of a gliding joint between the carpals, allowing for smooth, sliding motions. In contrast, Option A misrepresents the knee joint as having limited movement, while it is actually a hinge joint that allows for more extensive motion. Option B correctly notes the fluid-filled cavity but incorrectly identifies the joint between the coxal bones, which is a ball-and-socket joint rather than a standard synovial joint. Finally, Option C erroneously categorizes skull bones as synovial joints; they are connected through fibrous joints, lacking a synovial cavity altogether.

Q77. Tay Sach's disease is caused by absence of enzyme required to breakdown _.

• A. Lipids✓
• B. Glycogen
• C. Glucose
• D. Proteins

Explanation: Tay-Sachs disease is a inherited disorder that progressively destroys nerve cells (neurons) in the brain and spinal cord. It is caused due to the mutation in the gene which is responsible for producing enzyme involved break down of fatty substance.

Q78. The diagram shows some of the muscles and bones of the human arm.

• A. The tricep contracts to bend the elbow and the bicep relaxes.
• B. The bicep contracts to straighten the elbow and the tricep relaxes.
• C. The tricep contracts to straighten the elbow and the bicep relaxes.✓
• D. The bicep contracts to bend the elbow and the tricep relaxes.
• E. Both A and C are correct.

Explanation: The correct answer is that the tricep contracts to straighten the elbow and the bicep relaxes. In the human arm, the tricep and bicep are antagonistic muscles, meaning they work in opposition to each other to create movement. When the tricep contracts, it exerts force on the bones of the arm, causing the elbow to extend or straighten. During this action, the bicep must relax to allow the movement to occur smoothly. Option A is incorrect because the tricep does not bend the elbow; the bicep is responsible for bending the elbow by contracting. Option B is incorrect because the bicep does not straighten the elbow; that is the function of the tricep. Option D describes the action of bending the elbow, which is not the focus of the question about straightening the elbow. Option E is incorrect because it includes Option A, which is not correct.

Q79. The diagram represents the human respiratory system. While inhalation, which of the labelled muscles contract?

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

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

Q80. The respiratory pigment, which has much higher affinity to combine with oxygen, is:

• A. Myoglobin✓
• B. Haemoglobin
• C. Globin
• D. Hemocyanin

Explanation: Explanation:The respiratory pigment, which has much higher affinity to combine with oxygen is Myoglobin. The respiratory pigment, which has much higher affinity to combine with oxygen is Myoglobin, not Haemoglobin. This option is not correct because globin is a protein that makes up a part of haemoglobin. This option is also incorrect because hemocyanin is a respiratory pigment found in some invertebrates that uses copper rather than iron to bind to oxygen.

Q81. Enzyme substrate specificity is a result of which property of enzymes?

• A. The primary structure of enzymes
• B. The secondary structure of enzymes
• C. Tertiary structure of enzymes✓
• D. Quarternary structure of enzymes

Explanation: Tertiary structure of enzymes. Enzyme-substrate specificity arises from the unique three-dimensional shape of the enzyme's active site, which is determined by the enzyme's tertiary structure. The active site is a pocket or cavity on the surface of the enzyme that is specifically shaped to bind the substrate. The shape of the active site is complementary to the shape of the substrate, allowing them to fit together like a lock and key.

Q82. A pure breeding plant with the dominant phenotype of character P and the recessive phenotype of character Q was crossed with another pure breeding plant with the recessive phenotype of character P and the dominant phenotype of Q. The offspring of this cross were crossed with a double homozygous recessive for P and Q and the following results were obtained:22 were phenotypically dominant for P and recessive for Q5 were phenotypically dominant for both P and Q4 were phenotypically recessive for both P and Q24 were phenotypically recessive for P and dominant for QWhich one of the following types of Inheritance is illustrated by these results?

• A. Gene linkage of P and Q✓
• B. Independent segregation of P and Q
• C. Mendelian dihybrid Inheritance
• D. Multiple alleles
• E. Polygenic Inheritance

Explanation: When a pure breeding phenotypic dominant character P and recessive character Q is crossed with pure breeding recessive character P and dominant character Q, the cross is below:- PPqq X ppQQ will give PpQq. Now when this PpQq is crossed with recessive for both:- PpQq X ppqq will give PpQq ; Ppqq ; ppqq ; ppQq The ratio when there is a dihybrid cross between heterozygous character and homozygous recessive character is 9:3:3:1. However, the above ratio is not consistent with what it should be. This happens when there is a gene linkage between two characters

Q83. When a muscle bends one part upon the other, it is called

• A. abductor
• B. regulator
• C. extremor
• D. flexor✓

Explanation: The correct answer is flexor. Flexor muscles are responsible for bending or flexing at a joint, such as the biceps brachii, which flexes the forearm at the elbow. This action is the opposite of that performed by extensor muscles, which straighten a joint. The other options are incorrect: abductor muscles move limbs away from the body's midline, regulator is not a term used for muscles, and extremor is not a recognized term in muscle types.

Q84. The function of a cell wall in prokaryotes is:

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

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

Q85. Which of the following is not a true characteristic of spermatogonia?

• A. They develop into primary spermatocytes through mitosis
• B. They are undifferentiated
• C. They are germ line cells
• D. They are haploid✓

Explanation: Spermatogonia are diploid germ cells. They undergo mitosis to maintain the germ cell pool and differentiate into primary spermatocytes, which then undergo meiosis to produce haploid spermatids.

Q86. Purple non-sulphur bacteria is an example of which of the following?

• A. Heterotrophic bacteria
• B. Saprotrophic bacteria
• C. Chemosynthetic bacteria
• D. Photosynthetic bacteria✓

Explanation: Purple non-sulphur bacteria are classified as photosynthetic bacteria because they can produce their own food through photosynthesis using light energy, despite not requiring sulfur compounds for this process. They utilize bacteriochlorophyll and carotenoids to absorb light, which gives them their characteristic colors. The other options are incorrect as they describe bacteria with different methods of obtaining energy: heterotrophic bacteria from organic compounds, saprotrophic bacteria from decomposing matter, and chemosynthetic bacteria from inorganic chemical reactions.

Q87. Some substances lack definite heats of fusion. These substances are:

• A. Isomorphs
• B. Polymorphs
• C. Amorphous solids✓
• D. Crystalline solids

Explanation: 'Amorphous solids' do not possess any particular heat of fusion thus Option C is correct.'Crystalline solids' consist of atoms, ions, and molecules arranged in a definite and repeating three-dimensional pattern with definite heat of fusion.'Isomorphs' are substances with different chemical compositions, exhibiting the same structure.'Polymorphs' are multiple 3D structural forms of a substance.

Q88. Before a collision, molecules:

• A. Get faster
• B. None of these
• C. Stops
• D. Slow Down✓

Explanation: Before a collision, molecules tend to slow down instantaneously in order to react with each other.

Q89. When we calculate radii of Hydrogen atom by this equation r =.529A (n2) where n = 1,2,3,4,,the distance between orbits of hydrogen atom will

• A. Decrease
• B. Increase✓
• C. Remains same
• D. Be constant

Explanation: r∝n2 , Thus, as n increases r will also increase.

Q90. Which of the following is a factor affecting the rate of reaction?

• A. Amount of Substrate.
• B. Catalyst
• C. Temperature
• D. All of these.✓

Explanation: The major factors upon which the rate of a chemical reaction depends are:Amount of substrate/Concentration,Temperature,Catalyst, etc.Hence, all of the given options are correct.

Q91. The %age of nitrogen in ammonium nitrate is

• A. 46%
• B. 82%
• C. 33%✓
• D. 13%

Explanation: Ammonium nitrate, (NH4NO3), a salt of ammonia and nitric acid, used widely in fertilizers and explosives. The commercial grade contains about 33.5 percent nitrogen,

Q92. Half-life for 1st order reactions is:

• A. T½ = k/0.693
• B. T½ = 0.693/k✓
• C. None of these
• D. T½ = 0.693k

Explanation: The half-life of first-order reactions is given by the equation:T1/2 = 0.693/kwhere 'k' is the rate constant.

Q93. Benzene in the presence of AlCl3 produces acetophenone when reacts with:

• A. Acetyl chloride✓
• B. Acetic acid
• C. Ethyl benzene
• D. Ethanoic acid

Explanation: The benzene reacts with acetyl chloride in presence of anhydrous aluminum chloride to form acetophenone.

Q94. The decomposition of phosphorus pentachloride in the presence of moisture takes place by the following mechanism.The rate equation for this reaction will be:

• A. Rate = k [POCl3][H2O]3
• B. Rate = k [PCl5][H2O]✓
• C. Rate = k [PCl5][H2O]4
• D. Rate = [PCl5][H2O]5

Explanation: Rate = [PCl₅][H₂O] → The slow step controls the rate. Therefore, the rate law is written based only on the slow step.

Q95. The test used to distinguish among primary, secondary, and tertiary alcohols is:

• A. 2,4 - DNPH test
• B. Tollens test
• C. Lucas Test✓
• D. Fehling solution test

Explanation: The Lucas test is used to differentiate primary, secondary, and tertiary alcohols. It is based on the rate of turbidity formation due to alkyl chloride formation. Tertiary alcohols react fastest, secondary slower, and primary show little or no reaction.

Q96. In the reaction, 2SO2 (g) + O2 ⇌ 2SO3 (g) ∆H= -X cal most favorable conditions of temperature and pressure for a greater yield of SO3 are:

• A. Low temperature and low pressure
• B. High temperature and low pressure
• C. High temperature and high pressure
• D. Low temperature and high pressure✓

Explanation: The correct answer is Option D: Low temperature and high pressure. According to Le Chatelier's principle, increasing the pressure will shift the equilibrium towards the side with fewer gas moles, which is the product side (2SO3), resulting in a higher yield of SO3. Additionally, since the reaction is exothermic (∆H = -X cal), lowering the temperature will also favor the forward reaction, further increasing the yield of SO3. The combination of low temperature and high pressure is thus the most favorable for maximizing the production of SO3. Other options either incorrectly prioritize temperature and pressure conditions that do not favor the formation of SO3 or apply an incorrect understanding of Le Chatelier's principle.

Q97. The chemical reaction in which reactions require high amount of activation energy are generally:

• A. Slow✓
• B. First fast then slow
• C. First slow then fast
• D. Spontaneous

Explanation: The activation energy of a chemical reaction is closely related to its rate. Specifically, the higher the activation energy, the slower the chemical reaction will be. This is because molecules can only complete the reaction once they have reached the top of the activation energy barrier.

Q98. Which of the following compounds will form a hydrocarbon on reaction with Grignard reagent?

• A. CH3CH2OH✓
• B. CH3COOCH3
• C. CH3COCH3
• D. CH3CHO

Explanation: A Grignard reagent reacts with compounds containing active H atom, such as water, ammonia, amines, alcohols, alkynes etc., to form a hydrocarbon. It does not form hydrocarbon with ethanal and propanone. CH3CH2OH will form a hydrocarbon on reaction with Grignard's reagent as on reaction with Grignard's reagent −OH group will get replaced by the R− group of RMgX leading to the formation of hydrocarbon.

Q99. Due to the presence of a common ion, the solubility of a salt:

• A. Decreases✓
• B. Increases
• C. First decreases then increase
• D. Remain unchanged

Explanation: The presence of a common ion decreases the solubility of a salt in the solution. This is known as the common ion effect.

Q100. When the concentration of reactants are unit, the rate of reaction is then called _?

• A. Rate constant
• B. Both rate constant and velocity constant✓
• C. Velocity constant
• D. Reaction constant

Explanation: The rate of reaction is given by Rate of reaction = k [A] [B] where k is rate constant or velocity constant and [A] [B] are the concentrations of reactants When the concentration of reactants is equal to unity then Rate of reaction = k [1][1] Rate of reaction = k Thus when the concentration of reactants is equal to unity then the rate of reaction is equal to the rate constant also known as velocity constant.

Q101. 1 liter of a gas weighs 2 g at 300 K and 1 atm pressure. If the pressure is made 0.75 atm, at which of the following temperatures will 1 L of the same gas weigh 1 g?

• A. 450 K✓
• B. 800 K
• C. 600 K
• D. 900 K

Explanation: So we know that,P₁V₁ / P₂V₂ = W₁T₁ / W₂T₂Substituting in the above formula we get,=> 1 × 1 / 0.75 × 1 = 2 × 300 / 1 × T₂=> 1 / 0.75 = 600 / T₂Cross Multiplying we get,=> T₂ × 1 = 600 × 0.75=> T₂ = 450 K

Q102. Keeping inview the values of standard reduction potential given above, which one of the following would you select as a feasible redox chemical reaction?

• A. Cl- + I2 -> Cl2 + 2I-
• B. Cu + Zn2+ -> Cu2+ + Zn
• C. Mg + 2H + -> Mg2+ + H2✓
• D. 2Au + 6H+ -> 2Au3+ + 3 H2

Explanation: For a redox reaction to be feasible, the emf of it must be positive. (NOTE: When calculating emf, you take the voltage of each half equation according to the scenario, i.e. one will exhibit the same order as those shown above so, the E value is directly taken, but for some, you have to reverse the sign of the E value since the reaction, itself, is reversed).In option A, the emf is = -1.36 + 0.54 = -0.82, so NOT FEASIBLE. In option B, the emf is = -0.34 -0,76 = -1.10, so NOT FEASIBLE.In option C, the emf is = 2.37 + 0.00V = 2.37 so, it IS FEASIBLE; answer is C.In option D, the emf is = -1.50 + 0 = -1.54 (the coefficient of the reaction is not taken into account) so, it is NOT FEASIBLE.

Q103. What will be the product of the following reaction?

• A. A
• B. B
• C. C
• D. D✓

Explanation: Step 1: Starting compoundWe have p-cresol (4-methylphenol).Step 2: Reaction with CHCl₃/NaOHThis is the Reimer–Tiemann reaction.In this reaction, an aldehyde group –CHO gets introduced at the ortho position to the –OH group.So product A is o-formyl-p-cresol (4-methyl-2-hydroxybenzaldehyde).Step 3: Reaction with HCNAn aldehyde reacts with HCN to give a cyanohydrin.The –CHO group becomes –CH(OH)CN.So compound B is o-(CH(OH)CN)-p-cresol.Step 4: Hydrolysis with H₃O⁺On hydrolysis, –CN group converts to –COOH.So the final product C is o-(CH(OH)COOH)-p-cresol.Step 5: Match with given optionsLooking at the options:(a) has –CH₂COOH (wrong, no hydroxyl group)(b) also has –CH₂COOH (wrong)(c) has –CH(OH)COOH but with two methyls (wrong position)(d) has –CH(OH)COOH correctly at the ortho position to OH, with a para –CH₃ substituent (correct).

Q104. Three reactions are giveni. H2SO4 + 2HF ⟶ F2 + SO2 + 2H2Oii. H2SO4 + 2HBr ⟶ Br2 + SO2 + 2H2Oiii. H2SO4 + 8HI ⟶ 4I2 + H2S + 4H2OThe strongest reducing agent in these reactions is:

• A. HI✓
• B. HF
• C. HBr
• D. All of the above

Explanation: HI is the strongest reducing agent. The compounds having low dissociation energy are a stronger reducing agent than the others having high dissociation energy. The HI has low thermal stability as compared to HF, HCI, and HBr. HI can release H atoms easily as compared to HF, HCI, and HBr to reduce the other compound. The decreasing order of the reducing character is HI>HBr>HCl>HF

Q105. A child's balloon has a volume 3.80 dm3, when the temperature is 35°C. If the balloon is put in a refrigerator and cooled to 5°C, the approximate volume of the balloon is (assume pressure inside the balloon is equal to atmospheric pressure):

• A. 3.00 dm3
• B. 3.43 dm3✓
• C. 3.08 dm3
• D. 3.25 dm3
• E. 0.54 dm3

Explanation: To solve this, we apply Charles's Law, which states that at constant pressure, the volume of a gas is directly proportional to its temperature in Kelvin. Start by converting the given temperatures from Celsius to Kelvin: T1 = 35°C + 273 = 308 K and T2 = 5°C + 273 = 278 K. Using the formula V1/T1 = V2/T2, we have:3.80 dm3 / 308 K = V2 / 278 K.Solving for V2 gives:V2 = (3.80 dm3 * 278 K) / 308 K = 3.43 dm3.Thus, the correct answer is 3.43 dm3. The other options either miscalculate the proportional change or do not apply Charles's Law correctly.

Q106. The shielding effect increases?

• A. Down the Group✓
• B. Along the period
• C. Diagonally
• D. Only along the d-block

Explanation: As you go down the group, the period number increases, thus a new subshell is added.This leads to an increased shielding effect as more subshells are present to lessen the nuclear attraction experienced by valence electrons.

Q107. By heating 25g of limestone (CaCO3) , the weight of carbon dioxide produced is:

• A. 14 g
• B. 71 g
• C. 11 g✓
• D. 2 g
• E. 10 g

Explanation: Limestone is primarily composed of calcium carbonate (CaCO3). When heated, it decomposes according to the reaction:CaCO3 --> CaO + CO2From the stoichiometric relationship, 100g of CaCO3 decomposes to produce 44g of CO2. Therefore, for 25g of CaCO3, the amount of CO2 produced is calculated as follows:(25g CaCO3 / 100g CaCO3) * 44g CO2 = 11g CO2Thus, the correct answer is 11g. Other options either overestimate or underestimate this calculated mass based on incorrect stoichiometric assumptions.

Q108. In the figure given below, the electron flow in external circuit is from:

• A. Copper to zinc electrode
• B. Right to left
• C. Porous partition to zinc electrode
• D. Zinc to copper electrode✓

Explanation: The electrons flow from the oxidation reaction (Zn (s) --> Zn2+ (aq) + 2 e-) to the reduction half-cell (Cu2+ (aq) + 2 e- --> Cu (s)).So the electrons flow from the left to the right (zinc to copper electrode).

Q109. Fused Bauxite is electrolyzed to get:

• A. Sodium
• B. Magnesium
• C. Aluminum✓
• D. lron

Explanation: Option A) Sodium is not obtained by electrolysis of fused bauxite. Sodium is usually obtained by the electrolysis of molten sodium chloride (NaCl).Option B) Magnesium is not obtained by the electrolysis of fused bauxite. Magnesium is usually obtained by the electrolysis of molten magnesium chloride (MgCl2).Option C) The bauxite is purified to yield a white powder- aluminium oxide (also known as alumina)–from which aluminium can be extracted. The extraction is done by electrolysis, but first, the aluminium oxide must be melted so that electricity can pass through it. Option D) Iron is not obtained by the electrolysis of fused bauxite. Iron is usually obtained from iron ore through processes such as smelting and reduction of carbon.

Q110. Why does Cr show 3d54s1 configuration instead of 3d44s2?

• A. Because it is transition element
• B. Because it shows different oxidation states
• C. Because of extra stability of half filled d5 system✓
• D. Because it is typical transition element

Explanation: The correct answer is: Because of the extra stability of the half-filled d5 system. The electron configuration of chromium (Cr) is often represented as 3d5, 4s1 instead of 3d4, 4s2. This is because the configuration of 3d5, 4s1 provides a half-filled d-orbital, which offers extra stability compared to the 3d4, 4s2 configuration.

Q111. For a reaction given below C(s) + O2 (g) -> CO2 (g) -394 kJ / molThe enthalpy of reaction is

• A. 394 kJ / mol
• B. -394 kJ / mol✓
• C. 197 kJ / mol
• D. -197 kJ / mol

Explanation: The formation of carbon dioxide from carbon and oxygen is an exothermic reaction, meaning it releases heat. The enthalpy change, denoted as ΔH, is negative for exothermic reactions. In this case, the reaction releases 394 kJ/mol of energy, so the correct enthalpy change is -394 kJ/mol. The negative sign is crucial as it indicates the direction of heat flow (from the system to the surroundings). Option B correctly reflects this with -394 kJ/mol. The other options are incorrect either due to the wrong sign or incorrect magnitude.

Q112. The rate of a reaction in general can be increased by all the following factors except:

• A. by increasing temperature
• B. using a suitable catalyst
• C. by an increase in activation energy✓
• D. by increasing concentration of reactants

Explanation: Activation energy is inversely proportional to the rate of the reaction. When the activation energy increases, the rate of the reaction decreases. The addition of the catalyst increases the rate of the reaction. When the temperature of the reaction is increased or the concentration of the reactants is increased, the rate of the reaction increases.

Q113. The order of reaction for which half-life is inversely proportional to the concentration of reaction is?

• A. Second Order✓
• B. Zero Order
• C. First Order
• D. Third Order

Explanation: A second-order reaction is a type of chemical reaction that depends on the concentrations of a one second-order reactant or two first-order reactants. This reaction proceeds at a rate proportional to the square of the concentration of one reactant, or the product of the concentrations of two reactants.

Q114. What is the % relative humidity at 25 oC and 0.01876 atm if the vapor pressure of water is 23.76 mm Hg?

• A. 40%
• B. 50%
• C. 60%✓
• D. 70%

Explanation: Relative humidity is the ratio of the partial pressure of water vapor present in the air to the vapor pressure of water at a particular temperature, expressed as a percentage. In this question, we are given the vapor pressure of water (23.76 mm Hg) and the temperature (25 oC). We can use the formula: Relative Humidity = (Partial Pressure of Water Vapor / Vapor Pressure of Water) x 100 We need to first convert the given pressure of 0.01876 atm to mm Hg. 1 atm = 760 mm Hg, so 0.01876 atm = 14.268 mm Hg. Then, we can substitute the values in the formula: Relative Humidity = (14.268 / 23.76) x 100 = 60% Therefore, the % relative humidity at 25 oC and 0.01876 atm is 60%.

Q115. Beryllium(Be) shows the diagonal relationship with:

• A. Al✓
• B. B
• C. Mg
• D. Na

Explanation: The elements of the 2nd period, show resemblance in properties with elements of the 3rd period, placed diagonally. This is called the diagonal relationship. Beryllium (Be) shows a diagonal relationship with aluminum (Al).

Q116. Electrophile in sulphonation of benzene is:

• A. HSO4-
• B. H2SO4
• C. SO3✓
• D. HSO3

Explanation: SO3 acts as an electrophile in sulphonation. Sometimes H2SO4 is also seen in equations in place of SO3 because H2SO4 dissociates to give SO3, which in turn acts as an electrophile that’s why B is not the best choice.

Q117. According to coulomb's law, the electrostatic forces of attraction between electron and nucleus are _ to its square of the radius.

• A. Directly proportional
• B. Inversely proportional✓
• C. Equal
• D. None of these options are correct

Explanation: OPTION A: This statement is incorrect. The electrostatic force is not directly proportional to the square of the radius.OPTION B: Coulomb's law states that the force of attraction or repulsion acting along a straight line between two electric charges is directly proportional to the product of charges and inversely to the square of the distance between them.OPTION C: The electrostatic force between two point charges is not equal to the square of the distance between them, but is inversely proportional to it.

Q118. Line spectrum of sodium contains _ colored line/lines separated by a definite distance

• A. one yellow
• B. two yellow✓
• C. two brown
• D. two golden

Explanation: The sodium line spectrum contains 2 bright yellow lines, also known as the Sodium D-Lines.

Q119. Study the following facts:Zn → Zn+2 + 2e― Eo = +0.76 VCu → Cu+2 + 2e― Eo = – 0.34 V

• A. Cu + Zn+2 → Cu+2 + Zn
• B. Cu+2 + Zn+2 → Cu + Zn
• C. Cu+2 + Zn → Cu + Zn+2✓
• D. Cu+2 + Zn+2 → Cu + Zn+2

Explanation: The half cell equation with the lower Eo is the anode. Electrons travel from cathode to anode. (Flip the equation with the lower Eo and then 2e cancel out).the correct redox reaction involving Cu and Zn is: Cu+2 + Zn -> Cu + Zn+2Cu+2 + Zn -> Cu + Zn+2: This equation represents a redox reaction between copper ions (Cu2+) metal (Zn). In this reaction, copper ions gain two electrons to form copper metal, while zinc atoms two electrons to form zinc ions. This reaction is a spontaneous redox reaction because the potential of copper ions (Cu2+) is lower than that of zinc ions (Zn2+). Therefore, copper ions reduced, and zinc metal is oxidized.

Q120. How many chain isomers are shown by C5H12?

• A. 5
• B. 4
• C. 3✓
• D. 2

Explanation: C5H12 can have 3 isomers.

Q121. In CCI4 , all C-Cl bonds are _ but molecule is _ overall:

• A. Polar, nonpolar✓
• B. Nonpolar, neutral
• C. Polar, neutral
• D. Neutral, nonpolar

Explanation: In CCl4, all C-Cl bonds are polar, but the molecule is nonpolar overall.Each C-Cl bond in CCl4 is polar due to the difference in electronegativity between carbon (C) and chlorine (Cl). Chlorine is more electronegative than carbon, so it attracts the electrons in the bond more strongly, leading to a partial negative charge on the chlorine atom and a partial positive charge on the carbon atom.However, the molecule CCl4 has a tetrahedral geometry with four identical polar C-Cl bonds arranged symmetrically around the central carbon atom. The dipole moments of these polar bonds cancel each other out, resulting in a molecule with no net dipole moment. This cancellation of dipole moments makes the molecule nonpolar.

Q122. Catalytic hydrogenation of alkenes exhibits:

• A. Substitution reaction
• B. Elimination reaction
• C. Addition reaction✓
• D. Condensation reaction

Explanation: Catalytic hydrogenation of alkenes exhibits addition reactions. Addition reactions in an unsaturated compound mean a compound that has a double bond can undergo addition reactions. The addition reactions can be classified into three main categories. Electrophilic addition: In these types of reactions, a species, that accepts an electron pair, attacks the electron-rich site of the double bond between carbon atoms. The reaction examples include the reactions of alkenes with hydrogen halides to give alkyl halides. Nucleophilic addition: In these types of reactions, species that have electron pairs, donate to form a chemical bond. These reactions usually occur in compounds having a carbonyl group like aldehydes or ketones. Free-radical addition: In these types of reactions, non-polar molecules form bonds with unsaturated compounds. These reactions occur when free radicals are formed. Free radicals are species that have unpaired valence electrons.

Q123. The stability in the following structure is due to the:

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

Explanation: The correct answer is that the stability in the structure is due to hydrogen bonding between the NH group of one peptide and the CO group of another peptide. This type of hydrogen bonding is characteristic of the alpha-helix structure in proteins, which is a common secondary structural motif. The backbone N−H group hydrogen bonds to the backbone C=O group of an amino acid located three or four residues earlier along the protein sequence, stabilizing the helical structure.Option A, Weak van der Waal’s forces, are generally too weak to provide significant stabilization in this context. Option B, Disulfide bridges, are not involved in secondary structure stabilization but rather in tertiary structure. Option C, Presence of unpaired electron in the structure, is unrelated to the stabilization of protein structures.

Q124. Those elements, with an electronic configuration of valence shell ns2 np6 show little tendency to react chemically, are called?

• A. Lanthanides
• B. Actinides
• C. Alkali metals
• D. Noble gases✓

Explanation: The reactivity of lanthanides is generally lower than that of the corresponding alkali and alkaline earth metals. Lanthanides are relatively unreactive with water and oxygen, and they do not readily dissolve in most acids. However, they can react with strong oxidizing agents, such as chlorine or fluorine, to form a variety of compounds. Actinides are highly reactive elements due to their large atomic and ionic radii, high charge densities, and the presence of f-orbitals, which make them more susceptible to oxidation and reduction reactions. The alkali metals are highly reactive metals, and their reactivity increases from top to bottom of the group. Noble metals include metals such as gold, silver, platinum, and palladium. These metals are characterized by their low chemical reactivity, which is due to the fact that they have a completely filled outermost electron shell.

Q125. Which group gives a yellow precipitate of triiodomethane when warmed with alkaline aqueous iodine?

• A. An amide group, CH3CONH2
• B. Ethyl ketone group, C2H5COR
• C. A primary alcohol group as in propanol, CH3CH2CH2OH
• D. Methyl ketone group, CH3COR✓

Explanation: In the case of ethanal, methyl ketone or a secondary alcohol with a methyl group in the alpha position, a pale yellow precipitate of iodoform or triiodomethane is formed.

Q126. The heat of a reaction can be calculated by using:

• A. Joule's Law
• B. Ohm's Law
• C. Hess's Law✓
• D. Faraday's Law
• E. Boyle's Law

Explanation: Hess' law states that the change of enthalpy in a chemical reaction (i.e. the heat of reaction at constant pressure) is independent of the pathway between the initial and final states. In other words, if a chemical change takes place by several different routes, the overall enthalpy change is the same, regardless of the route by which the chemical change occurs (provided the initial and final conditions are the same). Hess’s law allows the enthalpy change (ΔH) for a reaction to be calculated even when it cannot be measured directly.

Q127. What is the emf of Zn-Cu cell ?

• A. 1.01V
• B. 1.23V
• C. 1.1V✓
• D. 1.44V

Explanation: Standard cell potential of Zn-Cu cell is 1.1V.

Q128. Glucose(C6H12O6) is the most important nutrient in a cell for generating chemical potential energy, what is the mass percent of carbon in 1.5g of sample?

• A. 33%
• B. 40%✓
• C. 53.3%
• D. 6.67%

Explanation: The mass percent of the carbon in a 1.5g sample of glucose is approximately 40%. To determine the mass percent of carbon in a sample of glucose (C6H12O6), we need to calculate the mass of carbon in the sample and then express it as a percentage of the total mass. The molar mass of glucose is calculated as follows: C: 6 atoms x 12.01 g/mol = 72.06 g/mol H: 12 atoms x 1.01 g/mol = 12.12 g/mol O: 6 atoms x 16.00 g/mol = 96.00 g/mol Total molar mass of glucose: 72.06 g/mol + 12.12 g/mol + 96.00 g/mol = 180.18 g/mol Now, to find the mass of carbon in 1.5 g of glucose, we can use the molar mass ratio of carbon to glucose: Mass of carbon = (Mass of glucose / Molar mass of glucose) x Molar mass of carbon Mass of carbon = (1.5 g / 180.18 g/mol) x 72.06 g/mol Mass of carbon = 0.599 g Finally, we can calculate the mass percent of carbon in the sample: Mass percent of carbon = (Mass of carbon / Mass of sample) x 100 Mass percent of carbon = (0.599 g / 1.5 g) x 100 Mass percent of carbon = 39.93% Therefore, the mass percent of carbon in a 1.5 g sample of glucose is approximately 39.93%.

Q129. The enthalpy of certain reactions at 273 K is -20.75 kJ. The enthalpy of the same reaction at 373 K (if heat capacities of reactants and products are the same) will be:

• A. －20.75 kJ✓
• B. -2075 kJ
• C. Zero
• D. －20.75 x 373/273 kJ

Explanation: As it is provided in the given statement that heat capacities of reactants and products are the same, therefore there will be no energy change in the reaction. By Kirchoff's Rule; ∆Cp=∆H2-H1/T2-T1∆Cp(T2-T1)=∆H2-H1As, ∆Cp= 0 , ∆H2=H1 , therefore;H2= -20.75KJ

Q130. Which among the following gives ppt. with terminal alkynyl hydrogen?

• A. Ammonical silver nitrate
• B. Ammoniacal cuprous chloride
• C. Both A and B✓
• D. None of these

Explanation: Terminal alkynes have a slightly acidic hydrogen on the triple-bonded carbon. They react with ammoniacal silver nitrate to form silver acetylides with ammoniacal cuprous chloride to form copper(I) acetylides, both giving precipitates. Thus, both reagents can detect terminal alkynes.

Q131. Cyanohydrins can be synthesised from ketones through:

• A. Nucleophilic addition reaction✓
• B. Unimolecular nucleophilic substitution reaction
• C. Electrophilic substitution reaction
• D. Bimolecular nucleophilic substitution reaction
• E. Nucleophilic elimination reaction

Explanation: A cyanohydrin reaction is an organic chemical reaction by an aldehyde or ketone with a cyanide anion or a nitrile to form a cyanohydrin. This is a base-catalysed nucleophilic addition reaction.

Q132. One Calorie is equivalent to:

• A. 0.4184 J
• B. 41.84 J
• C. 4.184 J✓
• D. 418.4 J

Explanation: One calorie is defined as the amount of energy needed to raise the temperature of one gram of water by one degree Celsius. The correct conversion is 1 Calorie = 4.184 joules. Option A (0.4184 J) and Option B (41.84 J) are incorrect because they do not accurately represent the conversion rate. Option D (418.4 J) is incorrect as it overestimates the conversion factor. Understanding this conversion is essential when working with energy changes in thermochemical processes.

Q133. Which molecule is planar?

• A. SF4
• B. XeF4✓
• C. NF3
• D. SiF4

Explanation: In XeF4, there are two lone pairings. Ans. The electron geometry of Xenon is octahedral, but the molecular geometry is square planar. This is because there are six bonding electron pairs in Xenon, so it has an octahedral electron geometry, but two electron pairs in the centre are unbound and lone pairs.

Q134. The geometry of H2S and its dipole moment are:

• A. Angular and non-zero✓
• B. Angular and zero
• C. Linear and zero
• D. Linear and non-zero

Explanation: H2S has a bent geometry according to VSEPR. It has 2 lone pairs and 2 bond pairs and a bond angle of 92o degrees. The dipole moment is non-zero because sulfur is more electronegative than hydrogen and makes the molecule slightly polar. Thus, the geometry of H2S and its dipole moment are Angular and non-zero.

Q135. Solution contains 85.5 g of sucrose (C12H22O11) in 250 cm3. What is its molarity?

• A. 1 M✓
• B. 0.5 M
• C. 0.25 M
• D. 2 M

Explanation: Molarity is moles of a substance divided by the volume in liters or cubic decimeters. For moles, divide the given mass with the molar mass of sucrose, which is (12x12+22+11x16) 342 grams per mol. Number of moles is 85.5/342 which comes out to 0.25 mol. To convert 250 cubic cm to liters, divide by 1000, so this comes out to 0.25 liters.Molarity = 0.25/0.25 = 1M so, answer is A.

Q136. Molar heat of vaporization is the amount of heat required to convert one mole of:

• A. A liquid into its vapours at its boiling point✓
• B. Liquids into its vapours
• C. Solids into vapours
• D. Solid into liquid at its melting point

Explanation: Molar heat of vapourization refers to the conversion of one mole of a liquid to its vapors at a constant temperature, which is the boiling point of the liquid. That is why option A is correct.Option B is partially correct because vaporization refers to the conversion of a liquid to gas, however, at a constant temperature. Options C and D are incorrect because vaporization does not involve the conversion of solids to liquids.

Q137. The smallest number of molecules are present in?

• A. 3.6g of H2
• B. 4.8g of C2H5OH
• C. 2.8g of CO
• D. 5.4g of N2O5✓

Explanation: Using the formulas; Moles = mass in (g) / Mr no.of molecules = moles× Avogadro's constant. Moles= 5.4/108 = 0.05 mol No. of molecules = 0.05×6.022×1023 = 3.011×1022 Option D has the least number of molecules thus it is the correct option

Q138. In cannizzaro’s reaction, Benzyl alcohol is obtained from

• A. Benzaldehyde✓
• B. Benzene
• C. Picric acid
• D. Benzyl chloride

Explanation: Cannizzaro reaction between formaldehyde and benzaldehyde gives benzyl alcohol and formate ion.

Q139. The ionization energy of groups _ shows an abnormal trend?

• A. 3A & 4A
• B. 5A & 6A
• C. 6A & 4A
• D. 3A and 6A✓

Explanation: The ionization energies of group IIIA and VIA show abnormal trends because elements of these groups tend to lose electrons easily to become stable.

Q140. In the second period of elements, although oxygen lies next to nitrogen yet its ionization first energy is lower than that of nitrogen because?

• A. Oxygen is paramagnetic in character.
• B. Nuclear charger of oxygen is greater than nitrogen.
• C. Oxygen has higher electron affinity.
• D. In oxygen, there exists repulsion between pair of electrons present in the same orbital of valence shell.✓

Explanation: Option A is factually correct but has no bearing on ionization energy.Option B is factually correct as oxygen has one more proton in its nucleus than nitrogen, however, because of this, the ionization energy must increase, but in reality, the ionization energy of oxygen is lower than that of nitrogen.Option C is factually correct, but has no bearing on activation energy.Option D is correct because oxygen has 6 valence electrons compared to Nitrogen's 5 valence electrons so, the electronic configuration of the last shell of O is 2s2 2p4 compared with nitrogen's 2s2 2p3. In N, the p subshells have all three orbitals, singly filled with electrons whereby in oxygen, one p orbital has a pair of electrons. In this orbital, the two electrons exert repulsion which will lower the ionization energy due to a decrease in the effective nuclear force of attraction between the outermost electron and nucleus in the oxygen atom.

Q141. Power developed by a person on eating 100g of ice per minute is (Latent heat of ice is 80 cal/g):

• A. 130 W
• B. 560 cal/sec
• C. 560 J/sec✓
• D. None of these

Explanation: A mass of ice eaten by the man per second.m =100/60=5/3 g/sLatent heat of ice,L = 80 cal/g.Therefore, energy required per second by the man in eating the ice, i.e., power developed by the man.= mL =5/3 x 80 cal/s 3=5x80/3x4.2J/s=560W

Q142. In an inelastic collision, Momentum is _ and Kinetic Energy is _ respectively.

• A. Not conserved ; not conserved
• B. conserved ; not conserved✓
• C. Conserved ; conserved
• D. Not conserved ; conserved

Explanation: For elastic and inelastic collisions, momentum and total energy are always conserved provided no external force is applied; however, for inelastic collisions, kinetic energy is NOT conserved.

Q143. The charge on the electron and proton is reduced to half. If the present value of Rydberg constant is 𝑅, then the new value of Rydberg constant will be:

• A. 𝑅/2
• B. 𝑅/4
• C. 𝑅/8
• D. 𝑅/16✓

Explanation: Explaination is given in the image.

Q144. A galvanometer has a resistance of 20 ohms and a full-scale deflection when a current of 0.001 ampere flows in it. What is the value of the series resistance to convert it into a voltmeter of range 10 volts?

• A. 7780 ohms
• B. 9980 ohms✓
• C. 5580 ohms
• D. 4480 ohms
• E. 3380 ohms

Explanation: As we know that converting a galvanometer into a voltmeter,we use formula Rh=V/Ig -Rg where Rh is the series resistance V is the voltage Ig is a full-scale deflection Rg is the resistance of the galvanometer so by putting values: Rh=10/0.001 -20 Rh=9980 ohm

Q145. When a potential difference is applied across the ends of a uniform wire of length l and radius r, a current I flows in the wire. If same potential difference is applied to the ends of another wire of the same material but of length 2l and radius 2r, the current in the wire is:

• A. I/4
• B. 2I✓
• C. I
• D. I/2

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

Q146. The unstable atom means:

• A. Electrons are increasing
• B. Protons are increasing
• C. Neutrons are increasing
• D. Any of these✓

Explanation: Multi electronic species are unstable, it prefers to lose electrons and form a stable octet or duplet; a "higher proton and neutron" number means a heavier nucleus which is naturally radioactive, i.e. naturally unstable.An unstable atom also has excess internal energy, with the result that the nucleus can undergo a spontaneous change (change in the number of protons and/or neutrons) towards a more stable form.

Q147. If displacement-time graph is a curve, which of the following is correct?

• A. Area under graph represents displacement
• B. Gradient of the graph is constant
• C. Gradient of the graph repesents velocity✓
• D. Gradient of the graph represents acceleration

Explanation: Option A : In the displacement time graph, the area under the graph doesn't represent displacement. Option B : The gradient of the graph is not always constant. Option: C In the displacement time graph, the gradient of the graph represents the velocity. The slope of the displacement-time graph gives the velocity of an object while the slope of the distance-time graph gives the speed of an object. Option D : Gradient if the graph doesn't represent acceleration..it represents the velocity.

Q148. A pendulum undergoes simple harmonic motion. The phase difference between the displacement and the acceleration of the particle is:

• A. 0
• B. π/2
• C. π✓
• D. 3π/2

Explanation: We know that for a motion to be simple harmonic motion, a ∝ -xHere, minus sign indicates that both are directed on opposite sides, or they are anti-parallel.

Q149. The question is as follows:

• A. 1250 J
• B. l000J
• C. 3500J
• D. 2500 J✓

Explanation: This question requires use of calculus, and is beyond the scope of the pre-medical syllabus.

Q150. What will be the expression for the observed frequency, if the source is moving towards the observer?

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

Explanation: This option is the correct expression for the observed frequency when the source is moving towards the observer. The negative sign in the denominator reflects the decrease in distance between the source and the observer, leading to a higher frequency being perceived by the observer.

Q151. A ball moving horizontally with speed ‘v’ strikes the bob of a simple pendulum at rest. The mass of the bob is equal to that of the ball if the collision is elastic the bob will rise to a height:

• A. v2/g
• B. v2/2g✓
• C. v2/4g
• D. v2/8g
• E. v2/7g

Explanation: From the conservation of linear momentum before and after the collision, mv=(m+m)v′ ⟹v′=v/2 All the initial kinetic energy gets converted to gravitational potential energy at the maximum height. Thus, ½ (2m)v2=(2m)gh =>V2/2g

Q152. A star moving away from earth shows _.

• A. Green shift
• B. Red shift✓
• C. Blue shift
• D. None of these

Explanation: Option B is correct because: When an object moves away from us, the light is shifted to the red end of the spectrum, as its wavelengths get longer. Option C is incorrect because: If an object moves closer, the light moves to the blue end of the spectrum as its wavelengths get shorter. Options A and D are incorrect because: These options don’t fit the question.

Q153. A first harmonic stationary sound wave is produced in the air of the cylinder, which is half-filled with water. More water is added to the cylinder, and now first harmonic stationary wave is produced with a different frequency. What is the change in frequency and nature of displacement in air at the surface of the water?

• A. Nature of displacement = antinode change in frequency = decrease
• B. Nature of displacement = antinode change in frequency = increase
• C. Nature of displacement = node change in frequency = increase✓
• D. Nature of displacement = node change in frequency = decrease

Explanation: Since the cylinder is half-filled with water, we can treat this as a pipe where it is closed on one end and open on the other. The closed end is a node. Adding water would decrease the original length, change the node, and increase the frequency as the formula for frequency is F = V/2L and since the length is decreasing, the frequency is increasing. Hence Option C is correct.

Q154. A body is hanging from a rigid support by an extensible string of length L. It is struck inelastically by an identical body of mass m with horizontal velocity v =√2gl , the tension in the string increases just after striking by:

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

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

Q155. The power loss 𝑃 in a resistor is calculated using the formula: 𝑃 =𝑉2/R The uncertainty in the potential difference 𝑉 is 3% and the uncertainty in the resistance 𝑅 is 2%. What is the uncertainty in 𝑃?

• A. 4%
• B. 7%
• C. 8%✓
• D. 11%

Explanation: •The fractional error in V would be3×2=6•The fractional error in R would be2•So the fractional error of power would be equal to the sum of the fractional errors of both potential difference and resistance;6+3=8•NOTE= The given % error is multiplied by the power as in case of potential difference.

Q156. When a body moves in a circle, the angle between its linear velocity and angular velocity is always?

• A. 180°
• B. 0°
• C. 90°✓
• D. 45°

Explanation: The angle between the linear velocity and the angular velocity of a body moving in a circle is 90°.

Q157. Which one of the following properties is not exhibited by the longitudinal waves?

• A. Interference
• B. Reflection
• C. Diffraction
• D. Polarization✓

Explanation: In a transverse wave, the oscillations of the particles occur perpendicular to the direction of wave propagation. This allows for the possibility of aligning the vibrations in a specific direction, a property known as polarization.In contrast, longitudinal waves involve oscillations of particles parallel to the direction of wave propagation. Because of this parallel oscillation, longitudinal waves do not exhibit polarization. Sound waves, which are longitudinal waves, do not have a preferred direction for particle oscillations.

Q158. If μ is the permeability of the medium and ∈ permittivity of the medium then the value of √ 1 / μ . ∈. Is equal to _.

• A. Planck's constant
• B. Speed of sound waves
• C. Speed of ultrasound waves
• D. Speed of light✓

Explanation: The correct answer is the speed of light. The relationship between permeability (μ) and permittivity (∈) of a medium is fundamental in determining the speed of light (c) in that medium. Specifically, the speed of light is given by the equation c = √(1/μ∈). This is because the speed of light in a vacuum is defined by these electromagnetic properties. In contrast, Planck's constant is a quantum mechanical constant, while the speed of sound and ultrasound waves depend on the medium's mechanical properties rather than its electromagnetic ones.

Q159. A plane is moving with speed v at a height 'h' in the horizontal direction. The time taken to reach the ground is:

• A. √2g/u
• B. None of these
• C. √(2h/g)✓
• D. √(2u/g)

Explanation: If we solve the second equation of motion for time:h = ut + 1/2gt2Since it is moving with v velocity therefore the initial velocity u must have been zeroh = 1/2gt2t2 = 2h/gt = √2h/g

Q160. A _ is a positively charged particle with properties similar to the α-particle. Its mass is one fourth and charge is one half of that of an α-particle. It is smaller in size and carries less energy at the same velocity.

• A. Beta particle
• B. Gamma ray
• C. Neutron
• D. Proton✓

Explanation: The correct answer is a proton. A proton is a positively charged particle with a mass that is one fourth that of an alpha particle and a charge that is one half of an alpha particle, making it the particle described in the question.Beta particles are incorrect as they are negatively charged particles akin to electrons. Gamma rays are a form of electromagnetic radiation and do not have mass or charge. Neutrons have no charge, so they do not fit the description of a positively charged particle.

Q161. 1/Req = 1/Rl + 1/R2 + 1/R3 + ..... +1/Rn is the combination in

• A. Series
• B. Parallel✓
• C. Both of them
• D. None of them

Explanation: When resistors are connected in parallel, the potential difference across all the resistors is the same. The total current is given by,

Q162. Two forces, 5 N and 10 N are acting at ‘O’ and ‘P’ respectively on a uniform meter rod suspended at the position of center of gravity 50cm mark as shown in the figure.

• A. 80 cm
• B. 75 cm✓
• C. 70 cm
• D. 65 cm

Explanation: For the rod to bebalanced, the clockwise moment must be equal to the anticlockwise moment. 5*50=10*x 250/10=x x=25cm 50+25=75cm.

Q163. On a planet, a vertically-launched projectile takes 12.5 s to return to its starting position. The projectile gains a maximum height of 170 m. The planet does not have an atmosphere. What is the acceleration of free fall on this planet?

• A. 2.2 m s−2
• B. 8.7 m s−2✓
• C. 27 m s−2
• D. 54 m s−2

Explanation: Explanation is given below:

Q164. The number of down quarks in a proton is:

• A. 3
• B. 4
• C. 2
• D. 1✓

Explanation: The two types of particles that you need to know are hadrons and leptons. Particles that are affected by the strong nuclear force are called hadrons, like protons and neutrons. Leptons are particles that are affected by weak nuclear force, like electrons. Hadrons are made of quarks that have several flavors. Two of the aforementioned flavors are "up" and "down". The quark composition is such that the overall charge of the particle is maintained. If the particle in question is a proton, as in this case, the charge would be +1. Proton: u u d

Q165. If a cell of emf 2V and internal resistance 0.5 ohm is connected across a resistance R, the current that flows is the same as that when a cell of emf 1.5 V and internal resistance 0.3 ohms is connected across the same resistor. Then R= Ohm.

• A. 0.3✓
• B. 0.6
• C. 0.5
• D. 0.75

Explanation: Figure 1 describes the first cell and figure 2 describes the second cell, both carrying the same current i. i is the circuit current and to find R Using ohm's law for figure 1. V=IR V= i Req1 , where i is the circuit current and Req1 is the resistance of the first cell. Req1 = 0.5 + R (since they are in series the resistance are added) V= i Req1 2= i (0.5 + R) i = 2 / 0.5 + R — eq1 Using ohm's law for figure 2. V=IR V= i Req2I, where i is the circuit current, and Req2 is the resistance of the second cell. Req = 0.3 + R (since they are in series the resistance are added) V= i Req2 1.5 = i (0.3 + R) i= 1.5 / 0.3 + R —- eq2 Equating both eq1 and eq2 2 / 0.5 + R = .5 / 0.3 + R 0.6 + 2R = 0.75 + 1.5R 0.5R = 0.15 R = 0.15/0.5 R="0.3 ohms"

Q166. An object whose mass is 100 g starts from rest and moves with constant acceleration of 20 cm/s2. At the end of 8 s its momentum is _ in g cm/s.

• A. 500
• B. 8000
• C. 16000✓
• D. 33000
• E. 64000

Explanation: First, we convert the mass from grams to kilograms: 100 g = 0.1 kg. Then, using the equation v=u+at, we find the final velocity to be 1.6 m/s. Calculating the momentum using momentum = mass * velocity, we get 0.1 * 1.6 = 0.16 kg m/s = 16000 gram cm/s. Therefore, the correct momentum at the end of 8 seconds is 16000 gram cm/s. Option C is the correct answer.

Q167. Which of the following is an instrument for monitoring radiations:

• A. GM tube
• B. Radar
• C. Wilson cloud chamber
• D. Both A and C✓

Explanation: The Geiger-Mueller (GM) detector is a common portable instrument choice for a general laboratory radioactive material survey. GM detectors are capable of detecting alpha, beta, and gamma radiation. However, this instrument is limited by its ineffectiveness in detecting lower energy beta and gamma emitters.Radars send out electromagnetic waves as short pulses which may be reflected by objects in their path, in part reflecting to the radar. When these pulses intercept precipitation, part of the energy is scattered back to the radar.A cloud chamber, also known as a Wilson cloud chamber, is a particle detector used for visualizing the passage of ionizing radiation.

Q168. Which of the following statement shows that no work is done?

• A. Pushing a car to start it moving
• B. Lifting the weights.
• C. The moon Orbiting the earth.✓
• D. Writing an essay on a page.

Explanation: When the moon revolves around the earth, the displacement is normal to the direction of force on the moon. Therefore no work is done by the moon.Work is the dot product of force and displacement.W=F.dcos theta

Q169. The nuclear equation shown has a term missing. What is represented by the missing term?

• A. An antineutrino✓
• B. An electron
• C. A neutrino
• D. A positron

Explanation: Antineutrinos are produced in nuclear beta decay together with a beta particle (in beta decay a neutron decays into a proton, electron, and antineutrino).

Q170. If a cell of emf 2V and internal resistance 0.5 ohm is connected across a resistance R, the current that flows is the same as that when a cell of emf 1.5 V and internal resistance 0.3 ohms is connected across the same resistor. Then R= Ohm.

• A. 0.3✓
• B. 0.6
• C. 0.5
• D. 0.75

Explanation: Figure 1 describes the first cell and figure 2 describes the second cell, both carrying the same current i. i is the circuit current and to find R Using ohm's law for figure 1. V=IR V= i Req1 , where i is the circuit current and Req1 is the resistance of the first cell. Req1 = 0.5 + R (since they are in series the resistance are added) V= i Req1 2= i (0.5 + R) i = 2 / 0.5 + R — eq1 Using ohm's law for figure 2. V=IR V= i Req2I, where i is the circuit current, and Req2 is the resistance of the second cell. Req = 0.3 + R (since they are in series the resistance are added) V= i Req2 1.5 = i (0.3 + R) i= 1.5 / 0.3 + R —- eq2 Equating both eq1 and eq2 2 / 0.5 + R = .5 / 0.3 + R 0.6 + 2R = 0.75 + 1.5R 0.5R = 0.15 R = 0.15/0.5 R="0.3 ohms"

Q171. The flux is the region where magnetic field:

• A. Changes direction
• B. Changes strength
• C. Changes polarity
• D. Does not change✓

Explanation: Magnetic flux is defined as the number of magnetic field lines passing through a given surface area. It is a measure of the magnetic field's presence and intensity in a specific region. The correct answer is that the flux is the region where the magnetic field does not change because the definition of magnetic flux is static; it does not imply a change in direction, strength, or polarity. Option D is correct because it aligns with the fundamental definition of magnetic flux. The other options incorrectly associate flux with changes in direction, strength, or polarity, which do not define the static nature of magnetic flux.

Q172. An electron is situated midway between two parallel plates 0.5 cm apart. One of the plates is maintained at a potential of 60 volts above the other. The force on the electron is: (e = -1.6x10-19C)

• A. 1.82x10-15 N
• B. 3.00x10-16 N
• C. 1.92x10-15 N✓
• D. 3.00x10-15 N
• E. 5.00x10-15 N

Explanation: To solve this problem, we first calculate the electric field (E) between the parallel plates using the formula E = V/d, where V is the potential difference and d is the distance between the plates. Here, V = 60V and d = 0.5 cm = 0.005 m. Thus, E = 60V/0.005m = 12,000 V/m.Next, we apply the formula for the force on a charge in an electric field: F = eE. The charge of an electron is e = -1.6x10-19 C. Therefore, F = (1.6x10-19 C)(12,000 V/m) = 1.92x10-15 N.Option A is incorrect due to a possible miscalculation of E. Option B underestimates the force, likely from an error in applying the formula. Option D overestimates the force, possibly by using incorrect values. Option E significantly overestimates the force, indicating a misunderstanding of the relationship between V, d, and the resulting force.

Q173. A ball falls vertically and bounces on the ground. The following statements are about the forces acting while the ball is in contact with the ground. Which statement is correct?

• A. The force that the ball exerts on the ground is always equal to the weight of the ball.
• B. The force that the ball exerts on the ground is always equal in magnitude and opposite in direction to the force the ground exerts on the ball.✓
• C. The force that the ball exerts on the ground is always greater than the weight of the ball.
• D. Both A and C

Explanation: According to Newton’s Third Law of Motion, when a ball falls and bounces on the ground, the force that the ball exerts on the ground is always equal in magnitude and opposite in direction to the force the ground exerts on the ball. This is why Option B is correct. Option A is incorrect because the forces involved are not constant and equal to the weight of the ball. Option C is incorrect as it erroneously claims that the force is always greater than the weight of the ball, which is not necessarily true. Option D is incorrect because it includes both incorrect statements from Options A and C.

Q174. Under what condition an object will have zero displacement but non zero distance?

• A. Linear motion
• B. Circular motion✓
• C. Random motion
• D. Oscillation

Explanation: As the object moves around in a circular track, its perpendicular distance from the center remains unchanged, so we can say that there is zero change in displacement. However, during circular motion object does cover distance in a circular path, so the change in distance is non-zero.In oscillations, linear motion, and random motion there is a change in perpendicular distance from the origin point so displacement is non-zero that is why A, C, and D are incorrect.

Q175. If two sounds have the same wavelength in air at the same temperature, what other property must they also have in common?Intensity Amplitude Frequency

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

Explanation: If the two sounds have the same wavelength in air at the same temperature, it means they have the same speed of propagation in that medium. Since the speed of sound is constant, if the wavelength is the same, the frequency must also be the same. The relationship between frequency and wavelength is inversely proportionalv=f x wavelength

Q176. Astronomers calculate speed of distant stars and galaxies using which of the following phenomena:

• A. Beats
• B. Interference
• C. Superposition principle
• D. Doppler effect✓

Explanation: The Doppler effect is a phenomenon where the observed frequency of a wave changes depending on the relative motion between the source of the wave and the observer. This effect is commonly used in astronomy to determine the motion of celestial objects, such as stars and galaxies.In the context of astronomy, the most common application of the Doppler effect is the redshift or blueshift of light. When a celestial object is moving away from an observer, its light is shifted towards longer wavelengths (redshift), and when it is moving towards the observer, the light is shifted towards shorter wavelengths (blueshift).Astronomers can measure these shifts in the spectrum of light emitted by stars or galaxies to determine their radial velocity (motion along the line of sight). This information is crucial for understanding the dynamics of galaxies, the expansion of the universe, and other aspects of celestial motion and structure. The redshift of light from distant galaxies played a key role in the discovery of the expansion of the universe.

Q177. The temperature coefficient of resistance is expressed in :

• A. °C
• B. °C-1✓
• C. m°C-1
• D. None of these

Explanation: The temperature coefficient of resistance (TCR) is a measure of how much the resistance of a material changes with temperature. It is expressed in units of inverse temperature, typically degrees Celsius or Kelvin( °C-1 or K-1). The TCR is defined as the percentage change in resistance per degree Celsius of temperature change.

Q178. Oil droplets of mass m and charge q are dropped between two horizontal parallel plates. Air resistance is negligible. The droplets are falling at constant velocity when electric field strength between the plates is E. Which of the following is true?

• A. E-0
• B. E < mg/q
• C. E = mg/q✓
• D. E > mg/q

Explanation: The forces on the droplet will be due to gravitational pull (related to mass) and due to the applied electric fieldqE will be directed upwards while mg will directed downwards F= ma = qEo -mg = 0 The equation becomes qEo = mg And , Eo = mg/q Therefore only option C is correct

Q179. Identify the example/s of Static Equilibrium:I. A book lying on a horizontal tableII. A buildingIII. A bridge

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

Explanation: Static equilibrium occurs when the sum of all forces and torques acting on an object is zero, meaning the object is at rest or its center of mass is not accelerating. In the given examples:I. A book lying on a horizontal table is in static equilibrium as it is at rest and the forces acting on it, such as gravity and the normal force, are balanced.II. A building is in static equilibrium if it is stationary and not experiencing any net forces or torques that would cause motion.III. A bridge is in static equilibrium when the forces acting on it, including its own weight and any supporting forces, are balanced to prevent motion.Thus, option E is correct as all examples satisfy the conditions for static equilibrium, while the other options incorrectly omit one or more examples.

Q180. The energy supplied by the cell to the charge carriers is derived from the conversion of:

• A. Heat energy into chemical energy
• B. Chemical energy into electrical energy✓
• C. Solar energy into electrical energy
• D. Mechanical energy into electrical energy

Explanation: The correct answer is that the energy supplied by the cell to the charge carriers is derived from the conversion of chemical energy into electrical energy. This process occurs in both primary and secondary cells, where chemical reactions within the cell generate electrical energy that can be used to power devices. Option A is incorrect because endothermic reactions and the conversion of heat energy into chemical energy are not the processes occurring in conventional electrical cells. Option C is incorrect as it describes the function of solar cells, which are distinct from the electrochemical cells typically used in circuits. Option D is incorrect because converting mechanical energy into electrical energy is characteristic of generators, not cells or batteries used in standard electrostatic applications.

Q181. A gas is enclosed in a container fitted with a piston of cross-sectional area of 0.10 m2. The pressure of the gas is maintained at 8000 N/m2. When heat is slowly transferred, the piston is pushed up through a distance of 4.0 cm. If 42 J heat is transferred to the system during the expansion, what is the change in the internal energy of the system?

• A. 5 J
• B. 10 J✓
• C. 20 J
• D. 30 J
• E. 40 J

Explanation: To determine the change in internal energy, apply the first law of thermodynamics: ΔU = Q - W, where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.First, calculate the work done by the gas as it pushes the piston: W = P×A×d, where P = 8000 N/m², A = 0.10 m², and d = 0.04 m (converted from cm to m). This gives: W = 8000 × 0.10 × 0.04 = 32 J.Substitute into the first law: ΔU = 42 J - 32 J = 10 J. Thus, the change in internal energy is 10 J.Options A, C, D, and E are incorrect as they result from miscalculations or incorrect assumptions about the heat transferred or work done during the process.

Q182. Is it possible to separate north pole only from bar magnet?

• A. Yes
• B. No✓
• C. In some cases it is possible
• D. None of these

Explanation: Magnetism is a property that is caused due to separation of poles at atomic level. Even when the north pole is separated from the south pole, a new north pole is formed. So, we cannot separate the north pole from a bar magnet. Hence, option B is the correct option.

Q183. Three resistors of 6 ohms each, can be connected in all possible ways. The highest value of resistance that can be obtained (in ohms) is:

• A. 2 Ohms
• B. 4 Ohms
• C. 9 Ohms
• D. 18 Ohms✓
• E. 36 Ohms

Explanation: If we connect all three in series, combined resistance will be 6+6+6=18(Series combination always gives the highest combined resistance)If we connect all three in parallel, combined resistance will be 1/6 + 1/6 + 1/6 = 1/R so R = 2 Ohms(This is the lowest possible combined resistance)This cancels options A, B, C and E since the highest possible resistance must be equal 18 Ohms.

Q184. Two identical bodies have a velocity ratio 2 : 3. What is the ratio of kinetic energies?

• A. 9:4
• B. 3:2
• C. 4:9✓
• D. 2:3

Explanation: Formula for kinetic energy is given as ½ mv2. As the masses are the same so, the kinetic energy will be in the ratios of the square of their velocities.

Q185. The fractional change in resistance per kelvin is known as:

• A. None
• B. Temperature coefficient of resistance✓
• C. Thermal coefficient
• D. Volumetric coefficient of expansion
• E. Linear coefficient of expansion

Explanation: The fractional change in resistance per kelvin is called the temperature coefficient.The temperature coefficient of resistance is a measure of how much the electrical resistance of a material changes with temperature. It is expressed in units of ohms per ohm per degree Celsius (Ω/Ω/°C) or ohms per ohm per kelvin (Ω/Ω/K). This coefficient is denoted by the symbol α (alpha) and is an important factor in understanding and designing electronic circuits, particularly when dealing with components like resistors whose resistance can vary with temperatureResistance coefficient, abbreviated as K, a dimensionless number, is how much resistance to the flow an obstacle has. Volumetric coefficient increases in volume per unit original volume per Kelvin rise in temperature is called the coefficient of volumetric expansion.The ratio increase in length original length for the 1-degree rise in temperature is called the coefficient of linear expansion

Q186. Solve the following question:

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

Explanation: * In the balanced reaction, the 3 S atoms in Fe₂S₃ are oxidized to form the S in 2FeSO₄ and 1SO₂. * 2 S atoms go from -2 to +6: change = 2 × (6 - (-2)) = 2 × 8 = 16 electrons lost. * 1 S atom goes from -2 to +4: change = 1 × (4 - (-2)) = 1 × 6 = 6 electrons lost. * Total electrons lost = 16 + 6 = 22 electrons. The total number of electrons transferred is 22. Therefore, the n-factor is 22. The equivalent mass = M / n-factor = M/22.

Q187. Two point charges attract each other with an electric force of magnitude F. If the charge on one of the particles is reduced to one-half its original value and the distance between the particles is doubled, what is the resulting magnitude of the electric force between them?

• A. F
• B. 2F
• C. F/4
• D. F/8✓

Explanation: The electrostatic force of attraction or repulsion between to charges is given by Coulomb's Law:F = kq₁q₂/r² ---------- equation 1where,F = Electrostatic Forcek = Coulomb's Constantq₁ = magnitude of first chargeq₂ = magnitude of 2nd charger = distance between chargesNow, if we double the distance between charges and reduce one charge to one-half value, then the force will become:F' = kq₁'q₂'/r'²Where,q₁' = (1/2)q₁q₂' = q₂r' = 2rTherefore,F' = k(1/2 q₁)(q₂)/(2r)²F' = (1/8)kq₁q₂/r²using equation 1:F' = F/8As this is numerical thus only one answer is correct.

Q188. When an object is thrown upward, it rises to height h. How high is the object in terms of h, when it has lost ⅓ of its original kinetic energy?:

• A. H/2
• B. H/3✓
• C. H/4
• D. H/6

Explanation: When an object is thrown upward, its initial kinetic energy is gradually converted into potential energy as it rises. According to the conservation of energy, the loss in kinetic energy should equal the gain in potential energy.If the object has lost 1/3 of its original kinetic energy, this energy has been transformed into potential energy. Therefore, the object has gained potential energy equivalent to 1/3 of its original kinetic energy, which corresponds to a rise to 1/3 of its maximum height, H.Thus, the object is at a height of H/3 when it has lost 1/3 of its original kinetic energy. The other options are incorrect because they represent different fractions of energy conversion.

Q189. The magnetic field is produced in a solenoid depends on:

• A. Its length
• B. Its length and current in it
• C. Its length and number of turns in it
• D. The number of turns and current in it✓

Explanation: The correct answer is The number of turns and current in it. The magnetic field strength inside a solenoid is determined by the product of the current flowing through it and the number of turns per unit length. While the length of the solenoid influences the uniformity of the magnetic field, it does not significantly impact its strength. Thus, Option D is correct. Options A, B, and C incorrectly emphasize the length of the solenoid as a primary factor, which is not the case.

Q190. A test charge of 23 μC is at a point P where an external electric field is directed to the left and has a magnitude of 3.1 x106 N/C. If the test charge is replaced with another test charge of 13 μC, what happens to the external electric field at P?

• A. It remains the same✓
• B. It reverses direction
• C. It changes in a way that cannot be determined
• D. 3.1 x 105 N/C

Explanation: The presence of the test charge at point P does not affect the external electric field because it is much smaller than the source charges and does not produce a significant electric field. We can also see it mathematically as we can express the electric field at a point P as: E = F/Q Now when charge (Q) is replaced with a smaller charge, the force acting on it also decreases and the Electric Field (E) acting on it remains the same. Therefore, the correct option is A) It remains the same.

Q191. Critical angle is the angle of incidence in the denser medium for which the angle of refraction in the rarer medium is equal to:

• A. 0˚
• B. Angle of incidence
• C. Twice the angle of incidence
• D. 90˚✓

Explanation: Option D is correct. A 90˚ angle of refraction implies that the ray of light doesn’t enter the rarer medium. Option A is wrong because the angle is from the normal to the ray. Option B is wrong since that happens for total internal reflection for angles bigger than the critical angle. Option C could be right but only if the critical angle is 45˚.

Q192. When deuterium and tritium fuse together they form?

• A. Atom
• B. U atom
• C. N atom
• D. He atom✓

Explanation: Deuterium–tritium fusion is a type of nuclear fusion in which one deuterium nucleus fuses with one tritium nucleus, giving "one helium nucleus", one free neutron, and energy.

Q193. The coulomb constant is defined as: (E stands for epsilon here)

• A. 1 / 4(π E)✓
• B. 4 / (π E)
• C. 4(π E)
• D. π / 4E

Explanation: The following image shows the explanation for this question:

Q194. Essential parts:What should come next to it book

• A. Pages✓
• B. Learning
• C. Pictures
• D. Eraser

Explanation: The necessary part of a book is its pages; there is no book without pages. Not all books are writing books hence they don’t need erasers, and not all books have pictures Learning may or may not take place with a book.

Q195. Complete the series: AB, EF, _ ,MN:

• A. IJ✓
• B. RS
• C. WX
• D. MN

Explanation: AB→CD→EF→GH→IJ→KL→MNThe pattern is two alphabets and then two alphabets skipped.After EF we will skip GH hence the answer will be IJ.

Q196. During the past year, Jamshed saw more movies than Sadia.Sadia saw fewer movies than Dawood.Dawood saw more movies than Jamshed.If the first two statements are true, the third statement is

• A. True
• B. FALSE
• C. Uncertain✓
• D. None of these

Explanation: Statement 1 = Jamshed > Sadia (True) Statement 2 = Sadia < Dawood or Dawood > Sadia (True) Statement 3 = Dawood > Jamshed (Uncertain) Since Statement 1 and 2 both imply that Sadia has seen less number of movies than, both Dawood and Jamshed, there is uncertainty about who has seen more movies between Jamshed and Dawood as not enough information is given. It can either be Dawood > Jamshed > Sadia OR Jamshed > Dawood > Sadia.

Q197. Which of the following is classified as a main rock?

• A. Metamorphic
• B. Sedimentary
• C. Igneous✓
• D. Both Options A and B are correct

Explanation: Option A: Metamorphic rocks started as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Option B: Common sedimentary rocks include sandstone, limestone, and shale. These rocks often start as sediments carried in rivers and deposited in lakes and oceans. When buried, the sediments lose water and become cemented to form rock.Option C: Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.

Q198. Statement:According to reports, the childrens below age 10 are being aggressive because of mobile phones.Course of Action:I. Parents needs to be strict with their child.II. Parents need to be concerned and limit their screening time.

• A. Both of the courses of action follow
• B. None of the courses of action follow
• C. Only courses of action I follows
• D. Only courses of action II follows✓

Explanation: The root cause of children getting aggressive is their mobile phones hence limiting the time that children use their phones can solve this problem. Lenient parentage is not the problem plus strict parenting sometimes causes rebellious behavior.

Q199. Dependent cause/ Independent causes:I. The construction of dams has created an obstruction in the migration of animals. II. The animals of Amazon have turned into ferocious beasts, that are damaging the property as well as a threat to the lives of people.

• A. Statement I is the cause and statement II is its effect
• B. Statement II is the cause and statement I is its effect
• C. Both statements I and II are independent causes
• D. None of these options are correct✓

Explanation: The correct answer is 'None of these options are correct' because there is no causal relationship between the two statements. Statement I refers to the environmental impact of dam construction on animal migration, while Statement II describes a behavioral change in animals without any clear link to dam construction. Therefore, neither statement can be considered to be a cause or effect of the other.