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Sindh Mcat Nts 2007 — Solved Past Paper with Answers

All 100 MCQs from Sindh Mcat Nts 2007, solved with the correct answer highlighted and a full explanation for every question. This is a free MDCAT Sindh / DUHS past paper — no signup, no ads. Practise it interactively in timed mode, drill more with free MDCAT MCQs, or browse all Sindh / DUHS papers.

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Q1. The word closest in meaning to 'Competent' is:

  • A. Experience
  • B. Skilful✓
  • C. Knowledgeable
  • D. Dynamic

Explanation: Competent refers to having the necessary ability or skill to do something successfully.

Why the other options are wrong
  • A. While experience contributes to competence, it doesn't encompass the full range of skills and abilities. Competence can exist without extensive experience.
  • C. Knowledge is important for competence, but being knowledgeable doesn't necessarily mean one can effectively apply that knowledge in practical situations.
  • D. "Dynamic" suggests adaptability and energy, which are related but not synonymous with competence. Competence implies a consistent and reliable level of skill and effectiveness.

Q2. People get tensed during difficult situations. But this condition is not only with common people, but also the very much experienced psychologists get worried during their problems.The idea that the author is producing in this passage is:

  • A. Everyone gets worried during their problems✓
  • B. Even psychologists get worried during their personal problems
  • C. Difficult situations are faced by everyone
  • D. Common people face a lot of problems

Explanation: The second sentence gives us the clear answer to this question. It talks about how ‘feeling tensed during difficult situations’ is a phenomena that not just normal people but also experienced psychologists suffer from.

Why the other options are wrong
  • B. This option is incorrect because the passage only mentions that psychologists get worried during their problems, without specifying whether those problems are personal or professional. It does not specifically state that they are worried during their personal problems.
  • C. This option is incorrect because the passage talks about people getting tensed during difficult situations, but it does not necessarily imply that everyone faces difficult situations. The passage only discusses the emotional response to such situations.
  • D. This option is incorrect because the passage does not explicitly state that common people face a lot of problems. It mentions that people, including experienced psychologists, get worried during difficult situations, but it does not quantify the frequency or quantity of problems faced by common people.

Q3. The reason they gave was _, and they explained it _

  • A. Correct, correct
  • B. Correct, correctly✓
  • C. Correctly, correct
  • D. Correctly, Correctly

Explanation: The first blank requires an adjective, and the second blank requires an adverb. ‘Correct’ would be the adjective, and ‘correctly’ would be the adverb.

Why the other options are wrong
  • A. Option A is incorrect because it presents a redundancy by using the same word "correct" twice.
  • C. Option C is incorrect because it also creates redundancy by repeating the word "correctly."
  • D. Option D is incorrect due to the redundancy caused by using the same word "correctly" twice.

Q4. What is the synonym of the following word:Monotonous:

  • A. Limited
  • B. Conclusive
  • C. Extremist
  • D. Repeatedly✓

Explanation: Monotonoeus refers to something which is dull, tedious, and repetitious; lacking in variety and interest.

Why the other options are wrong
  • A. This term doesn't convey the same meaning as "monotonous." Monotonous refers to a lack of variety or repetitiveness, while "limited" pertains to a restriction or constraint.
  • B. This word doesn't share the meaning of "monotonous." "Conclusive" refers to something decisive or settling an issue, whereas "monotonous" relates to a repetitive and unvarying nature.
  • C. This term is unrelated to "monotonous." "Extremist" describes holding extreme views or advocating for radical actions, whereas "monotonous" refers to a lack of variation or tedious repetitiveness.

Q5. What is the antonym of the following word: Intensive:

  • A. Casual✓
  • B. Regressive
  • C. Progressive
  • D. Attentive

Explanation: Intensive refers to being concentrated on a single subject in a very thorough or vigorous manner. The opposite of this would be casual, which means to not be very concerned about something.

Why the other options are wrong
  • B. This term implies a backward or worsening movement, which is not opposite to "intensive" but rather suggests a different direction.
  • C. While this option indicates advancement, it doesn't directly contrast the idea of intensity as "monotonous" is about lack of variety or interest.
  • D. While attentiveness involves focus, it doesn't inherently oppose the concept of intensity, which relates more to the degree or amount of something.

Q6. What is the antonym of the following word:Precise

  • A. Concise
  • B. Comprehensive
  • C. Exaggerate✓
  • D. Explanatory

Explanation: Precise means being marked by exactness and accuracy of expression or detail. The opposite of this would be something which means to be overexemplified (exaggerate).

Why the other options are wrong
  • A. This is not the antonym because "concise" means brief and to the point, whereas "precise" means exact and accurate.
  • B. This is not the antonym because "comprehensive" means covering a wide range or including all aspects, whereas "precise" means being exact and specific.
  • D. This is not the antonym because "explanatory" means providing explanations or clarifications, whereas "precise" means being accurate and finely detailed.

Q7. Which part is incorrect in the following sentence?We heard on TV that the weather is not fine. We said that we should not go out?What must be changed in order to make the sentences correct?

  • A. We [in the first sentence]
  • B. We [in the second sentence]
  • C. That the weather
  • D. We should not go out?✓

Explanation: Since the second sentence is just a statement, it should not be ending on a question mark. A full-stop would be the better punctuation to use here.

Why the other options are wrong
  • A. This option is incorrect because the subject "We" should be followed by "heard" instead of "heard on TV."
  • B. This option is incorrect because it should be "We said that we should not go out." The repetition of "We" is unnecessary.
  • C. This option is incorrect because it should be "We heard on TV that the weather is not fine."

Q8. Which part is incorrect in the following sentence?We do not smoke because smoking can harmful our lungs.

  • A. Have not
  • B. To smoke
  • C. Smoking
  • D. Can harmful✓

Explanation: The word ‘be’ is missing between ‘can harmful’ and the addition of this would complete the sentence.

Why the other options are wrong
  • A. "Do not" is correct to express the negative action of not smoking.
  • B. "To smoke" is correct because it follows the verb "do not" to complete the negative action.
  • C. "Smoking" is correct as the gerund form of the verb, indicating the action that is harmful.

Q9. Many businessmen waste their time in checking their competitors businesses.Instead what they should do is try to improve their own style of working and bringthe amendments that are required to make their business prosper.What is the major takeaway point from the above paragraph?

  • A. Businessmen need to look after their competitors business as well.
  • B. Many businessmen just waste their time by poking into their competitors businesses
  • C. Businessmen can improve their business by improving their business strategies.✓
  • D. Handwork can make any business successful.

Explanation: Although both options B and C seem to be correct, the second sentence is usually where the author puts their point of view forward and the idea that is mentioned here is that businessmen should employ different and unique strategies to make their business prosper.

Why the other options are wrong
  • A. Option A is not correct. The major takeaway point from the paragraph is that businessmen should focus on improving their own working style and making necessary amendments to achieve business prosperity. This implies that they shouldn't spend excessive time solely on checking their competitors' businesses.
  • B. Option B (incorrect): The paragraph criticizes the wastage of time in checking competitors' businesses, implying that this is not a productive activity, making it incorrect as a major takeaway.
  • D. Option D (incorrect): The paragraph doesn't directly mention hard work as the key factor; instead, it emphasizes improving strategies and making necessary amendments for business prosperity.

Q10. What is a synonym of the following word?Acquaintance

  • A. Enemy
  • B. Object
  • C. Friend✓
  • D. Fatigue

Explanation: Acquaintance refers to a person one knows slightly, but who is not a close friend.Since the other options here are completely irrelevant, we will go with the answer "friend".

Why the other options are wrong
  • A. Incorrect - An acquaintance is someone you know, but an enemy is someone you have a hostile relationship with.
  • B. Incorrect - An acquaintance refers to a person you are familiar with, whereas an object is a tangible item.
  • D. Incorrect - Acquaintance and fatigue are unrelated; the former refers to familiarity with a person, while the latter is a state of exhaustion.

Q11. Which one of the following is a voluntary muscle?

  • A. Biceps✓
  • B. Cardiac
  • C. Stomach
  • D. Vessels

Explanation: Biceps muscles are the voluntary muscle type(those in our intentional control) as they belong to the group of muscles called skeletal muscles.Stomach and vessels have smooth muscles that are involuntary.Cardiac muscle type is also involuntary.

Why the other options are wrong
  • B. Cardiac muscle is involuntary and forms the heart, responsible for pumping blood.
  • C. Stomach contains smooth muscle, which is involuntary, aiding in digestion and movement of food.
  • D. Blood vessels have smooth muscle that regulates blood flow involuntarily.

Q12. Which one of the following plants store water in their parenchymatous cells?

  • A. Succulent Plants✓
  • B. Angiosperms Plants
  • C. Gymnosperms Plants
  • D. Xerophytic Plants

Explanation: Succulent plants are known for their ability to store water in specialized parenchymatous cells, allowing them to survive in arid and dry environments. These parenchymatous cells have the capacity to expand and store water, helping the plant endure periods of drought. Hence option A is correct.

Why the other options are wrong
  • B. Angiosperms encompass a wide range of flowering plants with various adaptations, but water storage in parenchymatous cells is not a defining feature.
  • C. Gymnosperms include conifers and other non-flowering plants, which typically do not store water in parenchymatous cells as a primary adaptation.
  • D. Xerophytic plants are adapted to survive in dry environments, but they may use various strategies, including reduced leaf surfaces and specialized tissues, rather than relying solely on parenchymatous cell water storage.

Q13. Which type of respiration is the most effective in frog?

  • A. Coetaneous✓
  • B. Lung
  • C. Pulmo-cutaneous
  • D. Through gills

Explanation: Cutaneous respiration in frogs and other amphibians may be the primary respiratory mode during colder temperatures. Some amphibians utilizing cutaneous respiration have extensive folds of skin to increase the rate of respiration.Hence option A is correct.

Why the other options are wrong
  • B. Lungs are less efficient due to limited surface area for gas exchange in frogs, hindering sufficient oxygen uptake for metabolism.
  • C. While frogs can respire through their skin, it's less effective than other methods due to limited skin surface area and dependence on moist environments.
  • D. Frogs lack gills in their adult form, so gill respiration is incorrect for them. Larval frogs (tadpoles) have gills, but these are not used in adult frogs.

Q14. ALL of the following are symptoms of hepatitis, except:

  • A. Deficit Immunity✓
  • B. Enlargement of liver
  • C. Fever and fatigue
  • D. Jaundice

Explanation: All are symptoms of hepatitis except deficit immunity.Hepatitis is inflammation of liver,which has nothing to do with body’s immunity.

Why the other options are wrong
  • B. Enlargement of the liver (hepatomegaly) is actually a common symptom of hepatitis, particularly in its early stages, due to inflammation and damage to the liver tissue.
  • C. Fever and fatigue are typical symptoms of hepatitis, often indicating the body's immune response to the infection.
  • D. Jaundice, characterized by yellowing of the skin and eyes, is a classic symptom of hepatitis, indicating liver dysfunction and the buildup of bilirubin.

Q15. O Group is universal donor because:

  • A. It has both A & B Antigens
  • B. No Antigens✓
  • C. A antigen
  • D. B Antigen

Explanation: O is a universal donor because it has no antigens so no immune response can be generated against it. It remains unrecognized in our body.

Why the other options are wrong
  • A. Group O has no A or B antigens on its red blood cells, making it a universal donor.
  • C. Group O has no A antigen on its red blood cells, making it a universal donor.
  • D. Group O has no B antigen on its red blood cells, making it a universal donor.

Q16. Most of the fruits belong to Family:

  • A. Poaceae
  • B. Fabaceae
  • C. Rosacea✓
  • D. Solanaceae

Explanation: Most of the fruits belong to the Rosaceae family,this is just a factual recall from book.

Why the other options are wrong
  • A. This family mainly includes grasses, not fruits. Grasses like wheat, rice, and maize belong to Poaceae.
  • B. While some legumes in this family produce fruits (pods), not most fruits belong to Fabaceae. Examples include beans and peas.
  • D. Although Solanaceae contains fruit-bearing plants like tomatoes and peppers, most fruits come from other families, like Rosaceae (apples, strawberries) and others.

Q17. Oxygen reacts with RuBP in the absence of CO2 to form:

  • A. PGA
  • B. PGA and phosphoglycolate✓
  • C. Oxaloacetate
  • D. ATP

Explanation: In the absence of O2 RuBP can react with O2 to form:RuBP+O2--->PGA + phosphoglycolate

Why the other options are wrong
  • A. PGA (Phosphoglycerate) is incorrect because oxygen reacts with RuBP (Ribulose-1,5-bisphosphate) in a process called photorespiration, leading to the formation of PGA and phosphoglycolate.
  • C. Oxaloacetate is incorrect because oxygen reacts with RuBP during photorespiration, not forming oxaloacetate.
  • D. ATP (Adenosine triphosphate) is incorrect because oxygen's reaction with RuBP during photorespiration does not directly lead to the formation of ATP.

Q18. Ringworm is caused by:

  • A. Bacteria
  • B. Virus
  • C. Neutrophils
  • D. Fungus✓

Explanation: Approximately 40 different species of fungi can cause ringworm; the scientific names for the types of fungithat cause ringworm are Trichophyton, Microsporum, and Epidermophyton.

Why the other options are wrong
  • A. Ringworm is not caused by bacteria. It is a fungal infection of the skin, hair, or nails.
  • B. Ringworm is not caused by a virus. It is caused by various species of dermatophyte fungi.
  • C. Neutrophils are a type of white blood cell involved in immune responses, but they are not the cause of ringworm.

Q19. The phytohormone responsible for Fruit development, bud sprouting, development of pollen tube and parthenocarpy is:

  • A. Auxin✓
  • B. Gibberellin
  • C. Cytokinin
  • D. Thallomycın

Explanation: Auxins play a role in cell division and differentiation, in fruit development, in the formation of roots from cuttings, in the inhibition of lateral branching (apical dominance), and in leaf fall (abscission)

Why the other options are wrong
  • B. Gibberellins are a group of plant hormones responsible for growth and development. They are important for initiating seed germination . Low concentrations can be used to increase the speed of germination, and they stimulate cell elongation so plants grow taller. They are naturally produced by barley and other seeds.
  • C. Cytokinin controls cell division and differentiation, but its main role isn't directly related to fruit development or pollen tube growth.
  • D. Thallomycin isn't a recognized phytohormone; it might be a typographical error or a less-known term.

Q20. Which protozoan class is totally parasite:

  • A. Protozoa
  • B. Plasmodium
  • C. Ciata
  • D. Sporozoa✓

Explanation: The Sporozoa are parasitic protozoans that lack locomotor organs. They have no cilia, no flagella, no pseudopods.

Why the other options are wrong
  • A. This option is incorrect because "Protozoa" is a general term for single-celled eukaryotic organisms, some of which are parasites, but not all protozoans are parasites.
  • B. This option is incorrect because "Plasmodium" is a genus of parasitic protozoa responsible for causing malaria in humans. However, not all protozoans belong to the Plasmodium genus.
  • C. This option is incorrect because "Ciata" does not correspond to any recognized or well-known class of protozoa. It seems to be a misspelling or a non-existent term.

Q21. Which structure in bacteria composed of polysaccharides and amino acids that prevents bacteria from antibiotics and increases its pathogenicity?

  • A. Flagella
  • B. Capsule✓
  • C. Cell Membrane
  • D. Cytoskeleton

Explanation: Bacterial structure that provides resistance to bacteria from antibiotics is its capsule. Flagella has no role in pathogenicity and resistance to antibiotics,its only primary function is to provide bacteria its motility.Cell membrane and cytoskeleton are not exposed to the outside environment hence are not pathogenic.

Why the other options are wrong
  • A. Flagella are bacterial appendages responsible for movement and have no role in antibiotic resistance or pathogenicity enhancement.
  • C. While the cell membrane controls the movement of substances, it doesn't directly contribute to antibiotic resistance or increased pathogenicity.
  • D. The bacterial cytoskeleton provides structural support and aids in cell division but doesn't have a primary role in antibiotic resistance or heightened pathogenicity.

Q22. Opening and closing of stomata is controlled by which of the following takingplace in the guard cells?

  • A. Tubidity
  • B. Turgidity✓
  • C. Flaccidity
  • D. Turgor Force

Explanation: The opening and closing of stomata is governed by increases or decreases of solutes in the guard cells, which cause them to take up or lose water.When guard cells take up water they become turgid and as a result the stomata close and when they lose water content the guard cells become less turgid and stomata open.

Why the other options are wrong
  • A. Option A is incorrect because stomatal opening and closing are not controlled by turbidity (cloudiness) but by factors related to water balance in guard cells.
  • C. Option C is incorrect because stomatal opening and closing are not regulated by flaccidity (loss of turgidity) of guard cells, but rather by changes in their turgidity.
  • D. Option D is incorrect because it is essentially synonymous with turgidity. Stomatal opening and closing are indeed controlled by changes in turgor pressure within guard cells, but the term "turgor force" is not a commonly used or recognized scientific term in this context.

Q23. Guanine always pairs with:

  • A. Thymine
  • B. Adenine
  • C. Cytosine✓
  • D. Uracil

Explanation: Guanine always pairs up with Cytosine and adenine always pairs up with thymine.This is what is known as Chargaff’s rule.

Why the other options are wrong
  • A. Thymine pairs with adenine in DNA, not guanine. This pairing forms two hydrogen bonds.
  • B. Adenine pairs with thymine in DNA, not guanine. This pairing involves two hydrogen bonds.
  • D. Uracil pairs with adenine in RNA, not guanine. This pairing involves two hydrogen bonds.

Q24. Formation of mRNA from DNA is called:

  • A. Translation
  • B. Transcription✓
  • C. Genetics
  • D. Mutation

Explanation: mRNA is formed from DNA as a result of the transcription process,with the use of an enzyme called RNA polymerase.Translation is the process by which mRNA is converted into a polypeptide chain.Genetics is actually the study of genes, genetic variations and heredity in organisms.Mutation is described as the alteration in the nucleotide sequence of the genome.

Why the other options are wrong
  • A. Translation is the process of protein synthesis where mRNA is decoded to produce a protein. It does not involve forming mRNA from DNA.
  • C. Genetics is the study of inheritance and variation in living organisms. It is a field of biology, not a process of forming mRNA from DNA.
  • D. Mutation is a change in the DNA sequence. While it can lead to changes in mRNA, it is not the process of forming mRNA from DNA.

Q25. In sickle cell anemia:

  • A. Valine is replaced by Glutamic Acid
  • B. Glutamic Acid is replaced by Valine✓
  • C. Glutamic Acid is replaced by Adenine
  • D. B-chain is replaced by Valine

Explanation: In sickle cell anemia(SCD),6th code of beta globin gene gets altered as CAA(glutamic acid) changes to CAT(Valine), as a result the whole haemoglobin becomes insoluble and precipitates.Hence the correct option is B.

Why the other options are wrong
  • A. Incorrect. In sickle cell anemia, Valine replaces Glutamic Acid in the beta-globin chain of hemoglobin, leading to abnormal hemoglobin formation.
  • C. Incorrect. Glutamic Acid is an amino acid, while Adenine is a nucleotide. Sickle cell anemia involves amino acid substitutions, not nucleotide changes.
  • D. Incorrect. The B-chain refers to the beta-globin chain of hemoglobin. Sickle cell anemia involves a mutation in the beta-globin gene, leading to the substitution of Valine for Glutamic Acid.

Q26. Photosynthetic bacteria use which of the following instead of H2O?

  • A. H2S✓
  • B. H2SO4
  • C. H2 Gas
  • D. Atomic Hydrogen

Explanation: Unlike plants, algae, and cyanobacteria, they do not use water as their reducing agent, and so do not produce oxygen. Instead, they use hydrogen sulfide, which is oxidized to produce granules of elemental sulfur.

Why the other options are wrong
  • B. Incorrect because photosynthetic bacteria do not use sulfuric acid as a replacement for water in their photosynthesis process. They typically use H2S (hydrogen sulfide) instead of H2O.
  • C. Incorrect because photosynthetic bacteria do not use molecular hydrogen gas as a substitute for water. They utilize hydrogen sulfide (H2S) or other reduced compounds.
  • D. Incorrect because photosynthetic bacteria do not use atomic hydrogen as a substitute for water. They primarily employ hydrogen sulfide (H2S) during their photosynthetic reactions.

Q27. Which of the following is a bacterial disease:

  • A. Leishmaniasis
  • B. Tetanus✓
  • C. Measles
  • D. Polio

Explanation: Tetanus is an infection caused by bacteria called Clostridium tetani.Leishmaniasis is a vector borne disease that is transmitted by sand flies and caused by obligate intracellular protozoa.Measles and Polio on the other hand are caused by viruses.

Why the other options are wrong
  • A. Leishmaniasis is caused by protozoa, not bacteria.
  • C. Measles is a viral disease caused by the measles virus, not bacteria.
  • D. Polio is a viral disease caused by the poliovirus, not bacteria.

Q28. In vitro fertilization is:

  • A. Fertilization of egg outside the body in lab✓
  • B. Fertilization within the female
  • C. Fertilization in water exclusively
  • D. Giving nutrition to fertilized egg

Explanation: In vitro fertilisation (IVF) is a process of fertilisation where an egg is combined with sperm outside the body.

Why the other options are wrong
  • B. Incorrect. In vitro fertilization (IVF) involves fertilizing an egg outside the female body, usually in a laboratory dish, not within the female reproductive system.
  • C. Incorrect. IVF takes place in a controlled laboratory environment, not in water. It typically involves fertilization in a specialized culture medium, not a natural aquatic environment.
  • D. Incorrect. IVF involves creating an embryo by combining sperm and egg outside the body, but providing nutrition to the embryo isn't the primary focus of the procedure; rather, it's about facilitating fertilization and early development.

Q29. Which statement about fungi is not true?

  • A. They have cellulose
  • B. They are heterotrophs
  • C. They have starch✓
  • D. They are coenocytic

Explanation: Reserve food materials in all the fungi is glycogen and oil but not starch. So, the correct option is 'Energy reserve of fungi is starch while the energy reserve if animals is glycogen'.

Why the other options are wrong
  • A. Fungi lack cellulose in their cell walls; instead, they have chitin. Cellulose is found in plant cell walls.
  • B. Fungi are indeed heterotrophs, meaning they obtain nutrients by absorbing organic matter from their environment.
  • D. While some fungi are coenocytic (lacking septa in their hyphae), many have septa dividing their hyphae into cells.

Q30. In AMYLOPECTIN the linkage is:

  • A. 1,3
  • B. 1,6✓
  • C. 2,6
  • D. 6,6

Explanation: Amylopectin is a branched-chain polysaccharide composed of glucose units linked primarily by α-1,4-glycosidic bonds but with occasional α-1,6-glycosidic bonds, which are responsible for the branching.

Why the other options are wrong
  • A. Incorrect because the correct linkage is α-1,6-glycosidic bonds.
  • C. Incorrect because the correct linkage is α-1,6-glycosidic bonds.
  • D. Incorrect because the correct linkage is α-1,6-glycosidic bonds.

Q31. Formation of annual ring is the result of the activity of:

  • A. Cork Cambium
  • B. Cork Cambium and Vascular cambium✓
  • C. Intracalary meristem
  • D. Lateral cabium

Explanation: Formation of an annual ring is the result of the activity of cork and vascular cambium.

Why the other options are wrong
  • A. Incorrect because cork cambium produces cork cells for the outer bark, not annual rings.
  • C. Incorrect as intracalary meristem is involved in elongation, not in the formation of annual rings.
  • D. Incorrect as lateral cambium isn't responsible for annual ring formation; vascular cambium produces annual rings by adding growth layers of xylem and phloem.

Q32. Following are the characteristics of arteries except:

  • A. They are Deep
  • B. They don't have valves
  • C. They have narrow lumen
  • D. They are thin walled✓

Explanation: Statement in D is wrong because arteries are not thin walled but are thick walled due to large amounts of smooth muscle and elastic tissue in their walls.All other statements from A to C are true.

Why the other options are wrong
  • A. Incorrect: Arteries can be deep or superficial, depending on their location in the body. Deep arteries lie deeper within tissues, while superficial arteries are closer to the body's surface.
  • B. Incorrect: Arteries do not have valves like veins do. Valves in veins help prevent backflow of blood, whereas arteries rely on their muscular walls to maintain blood flow in one direction.
  • C. Incorrect: Arteries generally have a relatively wide lumen to accommodate the higher pressure of blood being pumped from the heart. A narrow lumen would impede blood flow.

Q33. Forgetfulness, loss of memory and losing track of even the most familiar places are the progressive characteristics of whiçh disease:

  • A. Hutington's Disease
  • B. Parkison's disease
  • C. Alzeihmer's Disease✓
  • D. Kaposi's Sarcoma

Explanation: Progressive deterioration in a way in which a person starts losing his way and memory is the hallmark sign of Alzeihmer’s disease.Parkinson’s disease's hallmark sign is shaking and stiffness.Huntington disease is related with psychiatric episodes and thinking disabilities.Kaposi sarcoma (KS) is a cancer that causes patches of abnormal tissue to grow under the skin.

Why the other options are wrong
  • A. This genetic disorder primarily affects motor skills and cognition but doesn't typically cause early memory loss or getting lost in familiar places.
  • B. Mainly affects motor functions; memory loss and getting lost are not prominent features, although cognitive changes can occur in later stages.
  • D. Kaposi sarcoma (KS) is a cancer that causes patches of abnormal tissue to grow under the skin.

Q34. Nitrogen is the ultimate product of:

  • A. Fats
  • B. Carbohydrates
  • C. Proteins✓
  • D. Organic salts

Explanation: Nitrogen is the ultimate product of protein breakdown.

Why the other options are wrong
  • A. Fats primarily consist of carbon, hydrogen, and oxygen. Nitrogen is not a component of fats, so it cannot be the ultimate product of fats.
  • B. Carbohydrates are composed of carbon, hydrogen, and oxygen. Nitrogen is not a constituent of carbohydrates, ruling out its role as the ultimate product.
  • D. Organic salts contain elements like carbon, hydrogen, oxygen, and often other elements like sodium, potassium, etc. Nitrogen is not a defining component of organic salts.

Q35. Club Mosses belong to the sub-division:

  • A. Spermopsida
  • B. Pteropsida
  • C. Lycopsida✓
  • D. Psilopsida

Explanation: Club mosses belong to the subdivision of Lycopsida.

Why the other options are wrong
  • A. This is not correct because Club Mosses (Lycopodiopsida) do not belong to Spermopsida, which is not a recognized subdivision of plants.
  • B. Club Mosses do not belong to Pteropsida, which is a term not commonly used in modern plant classification.
  • D. Club Mosses are not classified under Psilopsida. Psilopsida usually refers to the whisk ferns, a different group of primitive vascular plants.

Q36. Which one of the following undergoes complete metamorphosis?

  • A. Grasshopper
  • B. Butterfly✓
  • C. Crab
  • D. Scorpion

Explanation: Butterflies, moths, beetles, flies and bees have complete metamorphosis.There are four stages in the metamorphosis of butterflies and moths: egg, larva, pupa, and adult.

Why the other options are wrong
  • A. Incomplete metamorphosis; nymphs resemble adults, gradually maturing.
  • C. Incomplete metamorphosis; young resemble adults, molt to grow.
  • D. Incomplete metamorphosis; young resemble smaller versions of adults, undergoing molts to mature.

Q37. The TMV first appeared on the leaves of Tobacco plant and was characterised by:

  • A. Wrinkling of leaves✓
  • B. Yellow patches on lamina surface
  • C. Falling off of the leaves
  • D. Transmission from one organism to another

Explanation: Symptoms of TMV appear as light and spotted areas in dark green on the leaves. The leaves of infected plants are often small, curled, and wrinkled.

Why the other options are wrong
  • B. This option is incorrect because the Tobacco Mosaic Virus (TMV) does cause yellow patches on the leaves, which is one of its characteristic symptoms. It doesn't make sense to say this option is incorrect.
  • C. This option is incorrect because TMV-infected leaves typically do not fall off the plant. Instead, they exhibit symptoms like yellowing, mosaic patterns, and curling, but the leaves generally remain attached.
  • D. This option is incorrect because TMV is a plant virus and is not typically transmitted between different organisms. It spreads primarily through mechanical contact, such as when infected plant sap comes into contact with healthy plants, or through human activities like handling infected plants.

Q38. Poikilotherms are the animals:

  • A. Whose arteries contract in cold temperature
  • B. Who have lot of stored body fats
  • C. Who maintain their body temperature constant
  • D. Hibernate during winter✓

Explanation: Reptiles and other poikilothermic animals bask in warm weather and must hibernate in winter. The body temperature of fishes must remain close to that of the surrounding water, because heat is lost directly into the water during respiration.

Why the other options are wrong
  • A. Incorrect: Poikilotherms are animals whose body temperature varies with the surrounding environment, and their arteries do not necessarily contract in cold temperatures.
  • B. Incorrect: Poikilotherms may have varying amounts of body fat, but this characteristic is not a defining feature of these animals.
  • C. Incorrect: Poikilotherms do not maintain a constant body temperature; instead, their temperature fluctuates based on the external conditions.

Q39. Skin color, height and intelligence vary in different people due to:

  • A. Pleiotropy
  • B. Epistasis
  • C. Polygenic inheritance✓
  • D. Crossing over

Explanation: Skin color,height and intelligence varies in different people a lot,it is because they are inherited polygenically,which brings a lot of variance in phenotype.Polygenic inheritance implies that a single phenotype is controlled by a lot of genes,which helps bringing in a lot of phenotypic variance.

Why the other options are wrong
  • A. Incorrect. Pleiotropy refers to a single gene influencing multiple traits. Skin color, height, and intelligence are influenced by multiple genes, not a single gene.
  • B. Incorrect. Epistasis involves the interaction of different genes where one gene masks the effects of another. Skin color, height, and intelligence are primarily influenced by polygenic inheritance, not gene interactions.
  • D. Incorrect. Crossing over occurs during meiosis and leads to genetic recombination. It does contribute to genetic diversity but not directly to the variation in skin color, height, or intelligence.

Q40. Where is glucose reabsorbed the most in kidneys?

  • A. Bowman's Capsule
  • B. Proximal Convoluted Tubule✓
  • C. Distal Convoluted Tubule
  • D. Loop of Henle

Explanation: Most of the glucose entering the tubular system is reabsorbed along the nephron segments, primarily in the proximal tubule, such that urine is almost free of glucose.

Why the other options are wrong
  • A. Glucose is filtered here but normally completely reabsorbed in the proximal convoluted tubule.
  • C. Limited glucose reabsorption; main site is proximal tubule.
  • D. Glucose reabsorption occurs primarily in proximal tubule; loop mainly handles water and ions.

Q41. How many Carbons are there in STEARIC ACID?

  • A. 15
  • B. 18✓
  • C. 05
  • D. 07

Explanation: Stearic acid ( C18H36O2 ) has 18 carbon atoms in total.

Why the other options are wrong
  • A. Incorrect because stearic acid ( C18H36O2 ) has 18 carbons.
  • C. Incorrect because stearic acid ( C18H36O2 ) has 18 carbons.
  • D. Incorrect because stearic acid ( C18H36O2 ) has 18 carbons.

Q42. What will be the product of Specific Heat and molecular formula?

  • A. Molar specific heat✓
  • B. Molar mass
  • C. Heat capacity
  • D. Molar heat

Explanation: The product of specific heat and molecular formula is called molar specific heat.

Why the other options are wrong
  • B. Molar mass is incorrect because it is unrelated to the product of specific heat and molecular formula.
  • C. Heat capacity is incorrect because it is not the product of specific heat and molecular formula, but rather the amount of heat required to raise the temperature of a substance.
  • D. Molar heat is incorrect as it is not a recognized term.

Q43. Which one is different from the others?

  • A. Propane
  • B. Benzene✓
  • C. Ethane
  • D. Methane

Explanation: Benzene is different from propane,ethane and methane because benzene is not a alkane, while others are.Benzene is a lot different with a complex alternating double bond structure.

Why the other options are wrong
  • A. Benzene is different from the others as it is an aromatic hydrocarbon with a ring structure, while options A (Propane), C (Ethane), and D (Methane) are aliphatic hydrocarbons with linear or branched structures.
  • C. Benzene is different from the others as it is an aromatic hydrocarbon with a ring structure, while options A (Propane), C (Ethane), and D (Methane) are aliphatic hydrocarbons with linear or branched structures.
  • D. Benzene is different from the others as it is an aromatic hydrocarbon with a ring structure, while options A (Propane), C (Ethane), and D (Methane) are aliphatic hydrocarbons with linear or branched structures.

Q44. Dilute CO2 is used in cure of?

  • A. H2SO4
  • B. NaOH
  • C. KOH
  • D. H2S poisoning✓

Explanation: H2S poisoning can be treated with dilute CO2 or nitrite therapy.

Why the other options are wrong
  • A. Dilute CO2 is not used to cure H2SO4 exposure. Treatment for sulfuric acid exposure involves water rinsing and seeking medical help.
  • B. Dilute CO2 isn't a treatment for NaOH exposure. Acidic solutions are used to neutralize NaOH exposure.
  • C. Dilute CO2 isn't a remedy for KOH exposure. Acids are typically used to neutralize potassium hydroxide (KOH) exposure.

Q45. Who observed radioactivity first?

  • A. Henry Becquerel✓
  • B. Rutherford
  • C. Newton
  • D. Bohr

Explanation: In one of the most well-known accidental discoveries in the history of physics, on an overcast day in March 1896, French physicist Henri Becquerel opened a drawer and discovered spontaneous radioactivity.

Why the other options are wrong
  • B. While Rutherford made significant contributions to understanding atomic structure, he did not observe radioactivity first; his work focused on the nucleus and gold foil experiment.
  • C. Newton lived before the discovery of radioactivity and did not contribute to its observation.
  • D. Bohr's model of the atom explained electron behavior but was not involved in the initial observation of radioactivity by Becquerel.

Q46. Unit of Specific Rate Constant for zero order reaction is:

  • A. Mol dm-3 s-1✓
  • B. Mol dm-3 s-2
  • C. Dm6
  • D. Mol2 dm-6 s-1

Explanation: Rate=k[A]0 When this happens ,since the order of reaction is 0, the units of specific rate constant will be equal to the units of actual rate,which are mol dm-3 s-1.

Why the other options are wrong
  • B. Incorrect because the unit for a zero-order reaction's rate constant is concentration/time, which is Mol dm-3 s-1, not Mol dm-3 s-2.
  • C. Incorrect because this unit doesn't have a meaningful representation for a zero-order reaction rate constant, which involves concentrations and time, not volume raised to a power.
  • D. Incorrect because the unit for a zero-order reaction rate constant is concentration/time, not concentration squared divided by volume squared and time.

Q47. Which rule is violated in this 1s2 ,2s2 ,2p6 ,3p6,4s2 :

  • A. Aufbaus's Principle✓
  • B. Hund's Rule
  • C. n+l rule
  • D. Paul's Exclusion Principle

Explanation: There should be a 3s2 before 3p6,according to the Aufbau’s principle.This is being violated here.

Why the other options are wrong
  • B. Incorrect because Hund's Rule states electrons fill degenerate orbitals singly before pairing up.
  • C. Incorrect because the n+l rule is used to determine the order of filling of orbitals, not for violation assessment.
  • D. Incorrect because the configuration follows Pauli's principle, with each orbital containing at most two electrons with opposite spins.

Q48. Atoms of sulphur and 6 oxygen atoms are held in a thionate molecule by?

  • A. Ionic Bond
  • B. Covalent Bond✓
  • C. Dative Bond
  • D. Polar Bond

Explanation: Atoms of sulfur and oxygen atoms are held together by covalent bonding.

Why the other options are wrong
  • A. Incorrect because an ionic bond involves the complete transfer of electrons from one atom to another, resulting in charged ions. In a thionate molecule, atoms share electrons, not fully transfer them.
  • C. Incorrect because a dative bond (also known as a coordinate covalent bond) is formed when one atom donates a pair of electrons to another. In a thionate molecule, the sharing of electrons is more equal between sulfur and oxygen.
  • D. Incorrect because while a thionate molecule may contain polar covalent bonds (unequal sharing of electrons), the overall molecule's structure involves covalent bonds and not the complete separation of charges seen in polar bonds.

Q49. How many lone pairs are present in H2O?

  • A. 2✓
  • B. 4
  • C. 1
  • D. 3

Explanation: A water molecule has two lone pairs as shown below:

Why the other options are wrong
  • B. Incorrect because a water molecule has two lone pairs.
  • C. Incorrect because a water molecule has two lone pairs.
  • D. Incorrect because a water molecule has two lone pairs.

Q50. How many C atoms are in Valeric Acid?

  • A. 7
  • B. 5✓
  • C. 6
  • D. 11

Explanation: Valeric acid is a straight-chain saturated fatty acid containing five carbon atoms. It has a role as a plant metabolite.

Why the other options are wrong
  • A. Incorrect: Valeric acid ( C5H10O2 ). This formula clearly states that it has 5 C molecules.
  • C. Incorrect: Valeric acid ( C5H10O2 ). This formula clearly states that it has 5 C molecules.
  • D. Incorrect: Valeric acid ( C5H10O2 ). This formula clearly states that it has 5 C molecules.

Q51. Pyrex Glass is also called:

  • A. Borosilicate✓
  • B. Potassium silicate
  • C. Calcium silicate
  • D. Sodium silicate

Explanation: Borosilicate glass(Pyrex) is a type of glass with silica and boron trioxide as the main glass-forming constituents. Borosilicate glasses are known for having very low call coefficients of thermal expansion (≈3 × 10−6 K−1 at 20 °C), making them more resistant to thermal shock than any other common glass.

Why the other options are wrong
  • B. Incorrect. Pyrex glass is primarily composed of borosilicate, not potassium silicate. Potassium silicate has different properties and applications.
  • C. Incorrect. Pyrex glass contains borosilicate, not calcium silicate. Calcium silicate is used in insulation and construction materials.
  • D. Incorrect. Pyrex glass is made from borosilicate, not sodium silicate. Sodium silicate is used in detergents, adhesives, and water treatment, with distinct properties from borosilicate.

Q52. On oxidation with KMnO4; ethyne does not form which of the following:

  • A. Formic Acid
  • B. Oxalic Acid
  • C. Glycol✓
  • D. CO2

Explanation: Ethyne can with KMnO4 react to form formic acid and oxalic acid as shown below:Ethyne can also react to form CO2 as shown below:Ethyne however can not in any way react to form glycols.

Why the other options are wrong
  • A. Ethyne (acetylene) is oxidized by KMnO4 to form formic acid. KMnO4's oxidative power allows the conversion of ethyne's triple bond into the carboxyl group (-COOH).
  • B. Ethyne can be oxidized by KMnO4 to form oxalic acid. KMnO4 cleaves the triple bond, yielding two carboxyl groups which combine to form oxalic acid.

Q53. Rate of reaction depends on what is in SN2 reactions?

  • A. R k [R-X] [n-4]
  • B. R= k[R-X])2
  • C. R= K [n4]-
  • D. R= K [n] [R-X]✓

Explanation: R= K [n] [R-X];SN2 mechanism implies that two molecules are involved in the determining the rate of reaction.The nucleophile as well organic molecules are those two molecules,as mentioned in option D,which is the correct answer.

Why the other options are wrong
  • A. Incorrect because the correct answer is R= K [n] [R-X].
  • B. Incorrect because the correct answer is R= K [n] [R-X].
  • C. Incorrect because the correct answer is R= K [n] [R-X].

Q54. Which one of the following compounds dissociate more readily?

  • A. ChloroAcetic Acid✓
  • B. Formic Acid
  • C. HCI
  • D. Ether

Explanation: Chloroacetic acid is the type of acid that has chlorine molecules attached to the organic acid.This makes the organic acid more electronegative making it lose electrons easily when dissolved in water.

Why the other options are wrong
  • B. Formic acid is a weak acid and dissociates to a lesser extent due to its higher pKa value.
  • C. HCl is a strong acid and readily dissociates in water, but it is not a compound that dissociates in a solvent other than water.
  • D. Ether is a nonpolar compound and does not readily dissociate in most solvents; it forms weak intermolecular interactions but doesn't ionize like acids.

Q55. In Triads what would be the mass of Bromine according to the law of triads Cl=35.5 I=126.5?

  • A. 81 a.m.u✓
  • B. 90 a.m.u
  • C. 79.5 a.m.u
  • D. 82 a.m.u

Explanation: By the definition of triads, the atomic weight of bromine must be approximately equal to the average atomic masses of chlorine and iodine.(35.5+126.5)/2=81 a.m.u.

Why the other options are wrong

    Q56. Enzymes are completely destroyed at which temperature?

    • A. 37°C
    • B. 98.6°F
    • C. 102°C
    • D. 100°C✓

    Explanation: This is the factual recall that enzymes get completely destroyed at 100 C.

    Why the other options are wrong
    • A. Enzymes are not completely destroyed at this temperature, but their activity might be reduced due to denaturation.
    • B. Similar to A, enzymes can experience reduced activity but not complete destruction at this temperature.
    • C. Enzymes can denature and lose activity at this temperature, but it's not a consistent temperature for complete destruction.

    Q57. Which of the following is an atom?

    • A. Fe
    • B. CO
    • C. H2
    • D. He✓

    Explanation: Helium (He) is an atom, a noble gas element with the symbol He. It has a nucleus with 2 protons and usually 2 neutrons, orbited by electrons.

    Why the other options are wrong
    • A. Iron (Fe) is a chemical element with the symbol Fe. It consists of a nucleus with protons and neutrons, surrounded by electrons.
    • B. Carbon monoxide (CO) is a molecule composed of two different atoms, carbon (C) and oxygen (O), bonded together.
    • C. Hydrogen gas (H2) is a molecule consisting of two hydrogen (H) atoms bonded together, not a single atom.

    Q58. The s-s bond is weaker than s-p or p-p because:

    • A. Radius of s orbits is short
    • B. Radial distribution of charge in s orbital✓
    • C. Distribution of charge at the Axis
    • D. Distribution of charge at Nodal Planes

    Explanation: Strength of sigma bond is directly proportional to directional character.Since p orbital has more directional character than s orbital. It means head on overlapping with p orbital should be more than that of s orbital.This is because s orbital has spherical symmetry so it is unidirectional where as in case of p orbital, the probability of finding an electron at a particular distance is greatest along the x, y, or z axis so p orbital is more directional in that axis.So order for strength of sigma bond should be:p-p > s-p > s-s

    Why the other options are wrong
    • A. The s-s bond strength isn't solely due to orbital radius; it's determined by orbital overlap and effective nuclear charge.
    • C. Charge distribution along the axis isn't the primary factor; it's about effective overlap of orbitals.
    • D. Charge distribution at nodal planes matters, but other factors (orbital overlap, effective nuclear charge) play a larger role.

    Q59. A sample in the ionization chamber of mass spectrometer is ionized by:

    • A. Electrons✓
    • B. Protons
    • C. Neutrons
    • D. Nucleus

    Explanation: Gas phase particles of the sample are ionized through a collision with a high energy electron yielding a positive ions.

    Why the other options are wrong
    • B. Gas phase particles of the sample are ionized through a collision with a high energy electron yielding a positive ion.
    • C. Neutrons are electrically neutral and cannot ionize the sample or contribute to the ionization process in a mass spectrometer.
    • D. Nuclei are positively charged and would repel the positively charged ions in the ionization chamber, causing interference and inaccurate measurements.

    Q60. The substance for the separation of isotopes is firstly converted into the:

    • A. Neutral state
    • B. Vapour state✓
    • C. Free state
    • D. Charged state

    Explanation: The substance is converted into a vapour state before separation. This process facilitates various isotopic separation techniques, capitalizing on differences in vaporization properties to achieve separation.

    Why the other options are wrong
    • A. Incorrect because isotopes have varying numbers of neutrons, making them inherently neutral. Separation typically involves exploiting differences in charge or mass.
    • C. Incorrect as most substances are already in a free state. Separation relies on altering their charge or physical properties.
    • D. Incorrect as not all isotopes have charge differences. Separation methods often involve exploiting mass differences for effective results.

    Q61. Which one of the following gases show more deviation of ideal behavior?

    • A. CO2✓
    • B. N2
    • C. H2
    • D. He

    Explanation: CO2 shows more deviation from ideal behavior due to its larger molecular size and stronger intermolecular forces. These factors lead to deviations in pressure, volume, and temperature relationships compared to ideal gases.

    Why the other options are wrong
    • B. Nitrogen gas shows less deviation from ideal behavior due to its relatively small molecular size and weak intermolecular forces.
    • C. Hydrogen gas exhibits less deviation from ideal behavior because of its small size and weak intermolecular forces, similar to nitrogen.
    • D. Helium gas displays the least deviation from ideal behavior due to its extremely low molecular weight and negligible intermolecular interactions.

    Q62. The total number of orbital in a shell are calculated by:

    • A. 2n
    • B. 2n2
    • C. 2x
    • D. n2✓

    Explanation: The total number of orbitals in a shell is calculated using the formula:Number of orbitals = n2Where "n" represents the principal quantum number of the shell. Each orbital can hold up to 2 electrons (with opposite spins) according to the Pauli exclusion principle.

    Why the other options are wrong
    • A. Incorrect because correct formula is n2.
    • B. Incorrect because correct formula is n2.
    • C. Incorrect because correct formula is n2.

    Q63. Crystalline solids show all of following properties except one, identify that:

    • A. Cleavage planes
    • B. Variable M.P✓
    • C. Geometrical shape
    • D. Allotropy

    Explanation: Variable M.P: Crystalline solids typically have a well-defined melting point (M.P) rather than a variable one.

    Why the other options are wrong
    • A. Crystalline solids have distinct cleavage planes along which they tend to break with smooth surfaces.
    • C. Crystalline solids have a well-defined geometric shape due to their ordered arrangement of particles.
    • D. Crystalline solids may exhibit allotropy, where different crystalline forms have different properties, but this is not the exception.

    Q64. Weight of 1dm3 of O2 at STP is:

    • A. 1.4384 gm✓
    • B. 1.6384 gm
    • C. 1.84 gm
    • D. 1.0384

    Explanation: To calculate the weight of 1 dm³ (cubic decimeter) of oxygen (O2) at STP (Standard Temperature and Pressure), we can use the ideal gas law equation:PV = nRT We want to find the weight, which is equal to the mass (m) of the oxygen. The number of moles (n) can be calculated using the ideal gas law as follows:n = PV / RTSubstitute the given values:n = (1 atm) * (1000 cm³) / ((0.0821 L atm / K mol) * (273.15 K))n ≈ 0.04463 molNow, we need to calculate the molar mass of oxygen (O2), which is approximately 32 g/mol.m = n * molar massm ≈ 0.04463 mol * 32 g/molm ≈ 1.42976 gRounding off to four decimal places:m ≈ 1.4384 g

    Why the other options are wrong

      Q65. Long chains of amino acids are coiled about one another into a spiral by:

      • A. Covalent bond
      • B. Hydrogen bond✓
      • C. Ionic bond
      • D. Van der wall's force

      Explanation: Long chains of amino acids in proteins are coiled into a spiral structure called an alpha helix through hydrogen bonds between the amino and carboxyl groups of adjacent amino acids.

      Why the other options are wrong
      • A. Covalent bonds involve sharing of electrons between atoms, not suitable for the described coiling mechanism.
      • C. Ionic bonds involve electrostatic attraction between charged ions, not the primary force involved in the described coiling.
      • D. These are weak intermolecular forces, not the dominant force responsible for the specific coiling pattern.

      Q66. The correct formula to calculate the maximum number of electrons in a subshell is:

      • A. 2n2
      • B. l = n+1
      • C. m = 2l+1
      • D. 2 (2l+1)✓

      Explanation: For a given shell, l, the number of subshells, ml=(2l+1) Since each subshell can accommodate 2 electrons of opposite spin, so maximum number of electrons in a subshell = 2(2l+1)=4l+2. Q. Maximum number of electrons in a subshell or an atom is determined by the formula: Q.

      Q67. Which of the following are oxidizing in natiure:

      • A. Cathode rays
      • B. Canal rays
      • C. Neutrons
      • D. Both B & C✓

      Explanation: The correct option is D. Both B & C (Canal rays and Neutrons) are oxidizing in nature.

      Why the other options are wrong
      • A. Cathode rays are streams of electrons and are generally reducing agents, not oxidizing agents. They have a tendency to gain electrons rather than cause oxidation.
      • B. Canal rays are positively charged ions that have a high energy and are capable of causing oxidation when they collide with other atoms or molecules.
      • C. Neutrons, despite being electrically neutral, can induce oxidation indirectly through nuclear reactions and interactions, leading to the formation of reactive species that can oxidize other substances.

      Q68. Which of the following particles would, on losing an electron, have a half filled set of p orbitals?

      • A. C-
      • B. N-✓
      • C. N
      • D. O4

      Explanation: Losing an electron results in the formation of a cation. For a half-filled set of p orbitals, the electron configuration should be 2p3. N- (Nitrogen ion) has an electron configuration of 1s2 2s2 2p3, making it the correct choice.

      Why the other options are wrong
      • A. C- would have an electron configuration of 1s2 2s2 2p2, which is not a half-filled set of p orbitals.
      • C. N has an electron configuration of 1s2 2s2 2p3, which is a half-filled set of p orbitals.
      • D. O4 is not a known species, and its electron configuration is not applicable.

      Q69. PH3 has _ shape?

      • A. Trigonal
      • B. Tetrahedral
      • C. Pyramidal✓
      • D. Linear

      Explanation: PH3, or phosphine, has a pyramidal shape. It consists of three hydrogen atoms bonded to a central phosphorus atom with a lone pair of electrons, resulting in a trigonal pyramidal geometry. The lone pair creates an electron repulsion that pushes the bonding hydrogen atoms downward, giving the molecule its pyramidal shape.

      Why the other options are wrong
      • A. Not correct. While PH3 does have a trigonal arrangement of atoms, the lone pair of electrons causes distortion from a purely trigonal planar geometry.
      • B. Not correct. PH3 does not have a tetrahedral shape, as the presence of a lone pair of electrons causes distortion from perfect tetrahedral symmetry.
      • D. Not correct. PH3 is not linear; it has a bent or pyramidal shape due to the repulsion between the lone pair and the bonding pairs of electrons.

      Q70. During electrolysis of dilute aqeous solution of H2SO4 , which specie is obtained at anode:

      • A. O2✓
      • B. SO2
      • C. H2
      • D. SO3

      Explanation: O2 is obtained at the anode during the electrolysis of dilute aqueous H2SO4. At the anode, water is oxidized to produce oxygen gas and protons.

      Why the other options are wrong
      • B. SO2 is not obtained at the anode in this electrolysis process. It is not a product of the anodic reaction.
      • C. H2 is obtained at the cathode, not the anode. Water is reduced to produce hydrogen gas and hydroxide ions at the cathode.
      • D. SO3 is not obtained at the anode during the electrolysis of dilute aqueous H2SO4. It is not a product of the anodic reaction.

      Q71. With the help of which one of the following waves Big Bang theory was proved?

      • A. X rays
      • B. Radiowaves
      • C. UV rays
      • D. Gamma rays✓

      Explanation: The Big Bang theory was supported by the discovery of Cosmic Microwave Background Radiation, which is primarily composed of low-energy microwaves. However, gamma rays played a crucial role too. Gamma-ray observations of distant galaxies helped confirm the theory's predictions about the early universe's hot and energetic conditions.

      Why the other options are wrong
      • A. X rays have limited relevance to the Big Bang theory, mostly used for studying high-energy astrophysical phenomena.
      • B. Important for cosmic microwave background radiation detection but less directly linked to Big Bang proof.
      • C. Not significant in directly proving the Big Bang theory, mainly used for studying celestial objects' characteristics.

      Q72. The dimensions of impulse are same as that of:

      • A. Momentum✓
      • B. Force/Time
      • C. Velocity
      • D. None of these

      Explanation: The impulse acting on an object is equal to the change in linear momentum of that object. The dimensions of linear momentum and change in linear momentum are the same. Hence, the dimensions of impulse will be the same as that of the momentum.

      Why the other options are wrong
      • C. Velocity and impulse have different dimensions.
      • D. Incorrect, as option B (Force/Time) is correct.

      Q73. The value of acceleration due to gravity is 9.8 m/s2. It's value in Km/min2 will be:

      • A. 35.3 Km/min2✓
      • B. 5.9 Km/min2
      • C. 58.8 Km/min2
      • D. 17.6 Km/min2

      Explanation: .

      Q74. Parsec is the unit of:

      • A. Time
      • B. Angular acceleration
      • C. Distance✓
      • D. Velocity

      Explanation: Parsec (parallax arcsecond) is a unit of distance used in astronomy to measure the vast distances between celestial objects. It's the distance at which an object would have a parallax angle of one arcsecond when observed from Earth.

      Why the other options are wrong
      • A. Parsec is not a unit of time. It's a measure of distance.
      • B. Parsec is not a unit of angular acceleration. It's related to distance.
      • D. Parsec is not a unit of velocity. It's a measure of distance.

      Q75. One kilometer is equal to:

      • A. 0.4 mile
      • B. 0.52 mile
      • C. 0.62 mile✓
      • D. 0.72 mile

      Explanation: One kilometer is approximately equal to 0.62 miles. This is a common conversion used in the metric system.

      Why the other options are wrong
      • A. Incorrect. This is not an accurate conversion.
      • B. Incorrect. This is not an accurate conversion.
      • D. Incorrect. This is not an accurate conversion.

      Q76. When two bodies stick together after collision, the collision is said to be:

      • A. Perfectly elastic
      • B. Complete inelastic✓
      • C. Partially elastic
      • D. None of these

      Explanation: In a complete inelastic collision, two bodies stick together after colliding and move as a single mass. Kinetic energy is not conserved, and momentum is conserved.

      Why the other options are wrong
      • A. Both momentum and kinetic energy are conserved, and there is no deformation.
      • C. Some kinetic energy is lost, and the bodies may bounce apart to some extent.
      • D. Not the correct option, as the correct answer is B (complete inelastic).

      Q77. Flight of rocket in the space is an example of:

      • A. First law of motion
      • B. Second law of motion
      • C. Third law of motion✓
      • D. Law of gravitation

      Explanation: Newton's third law of motion states that to every action there is an equal and opposite reaction. Similarly, when a rocket moves, it exerts the action force on the gases to expel them backwards which in turn exerts an equal and opposite reaction force to move the rocket forward.

      Why the other options are wrong
      • A. First law of motion (inertia): An object remains at rest or in uniform motion unless acted upon by an external force.
      • B. This law, formulated by Isaac Newton, states that the force applied to an object is directly proportional to its mass and the acceleration produced.
      • D. Law of gravitation: Describes the attractive force between masses, not directly related to rocket propulsion in space.

      Q78. Minimum number of equal forces that keep the body in equilibrium are:

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

      Explanation: Consider a particle having just one line of force acting on it. This force results in acceleration of the particle disturbing its equilibrium. The minimum number of equal forces required to keep a body in equilibrium is two. These forces must be equal in magnitude and opposite in direction to balance each other out and result in a net force of zero.

      Why the other options are wrong
      • B. Three forces can also keep a body in equilibrium if they form a closed triangle of forces, known as a "closed polygon of forces." However, the minimum number of equal forces required to keep a body in equilibrium is two.
      • C. Four forces can also keep a body in equilibrium if they form a closed quadrilateral of forces. However, the minimum number of equal forces required to keep a body in equilibrium is two.
      • D. Five forces can also keep a body in equilibrium if they form a closed pentagon of forces. However, the minimum number of equal forces required to keep a body in equilibrium is two.

      Q79. The engine of the car applies the forces of 2000N by which it moves with uniform velocity of 72Kmh-1. The power delivered by the engine is:

      • A. 2 kW
      • B. 40 kW✓
      • C. 44 kW
      • D. 144 kW

      Explanation: Given:Force (F) = 2000 NVelocity (v) = 72 km/h = 20 m/s (converted from km/h to m/s by dividing by 3.6) Substitute the values into the formula:P = 2000 N × 20 m/s = 40000 N·m/s = 40000 W Since 1 kW (kilowatt) = 1000 W, we can convert the power to kilowatts:P = 40000 W ÷ 1000 = 40 kW Therefore, the power delivered by the engine is 40 kW.

      Why the other options are wrong

        Q80. A light and heavy body have equal kinetic energy , which one has greater momentum?

        • A. The light body✓
        • B. The heavy body
        • C. Both have equal momentum
        • D. It is not possible to say anything without additional information

        Explanation: Two bodies with equal kinetic energy have different masses, so the higher body must have greater momentum according to the equation p = mv, where p is momentum and m is mass as explained below.

        Why the other options are wrong
        • B. Two bodies with equal kinetic energy have different masses, so the higher body must have greater momentum according to the equation p = mv, where p is momentum and m is mass as explained below.
        • C. Two bodies with equal kinetic energy have different masses, so the higher body must have greater momentum according to the equation p = mv, where p is momentum and m is mass as explained below.
        • D. Two bodies with equal kinetic energy have different masses, so the higher body must have greater momentum according to the equation p = mv, where p is momentum and m is mass as explained below.

        Q81. If a body of mass 2kg is raised vertically through 2m, then the work done will be:

        • A. 38.2 J
        • B. 39.2 J✓
        • C. 392.1 J
        • D. 3.92 J

        Explanation: When a body is raised vertically, the work done against gravity is given by the formula:Work = Force × Distance × cos(θ). In this case, the force is the weight of the body (mg), where m is the mass (2 kg) and g is the acceleration due to gravity (approximately 9.8 m/s²). The distance is 2 meters, and the angle θ between the force and displacement is 0° (since they are in the same direction). So, Work = (2 kg) × (9.8 m/s²) × (2 m) × cos(0°) = 39.2 J.

        Why the other options are wrong
        • A. According to given data, this option is incorrect as explained below.
        • C. According to given data, this option is incorrect as explained below.
        • D. According to given data, this option is incorrect as explained below.

        Q82. Who discovered the inverse square law for gravity?

        • A. Einstein
        • B. Newton's✓
        • C. Galileo
        • D. Plank

        Explanation: Sir Isaac Newton discovered the inverse square law for gravity. He formulated it in his law of universal gravitation, stating that the force between two objects is inversely proportional to the square of the distance between their centers of mass.

        Why the other options are wrong
        • A. Developed the theory of general relativity, extending gravitational understanding beyond Newton's laws.
        • C. Pioneered observational astronomy and physics but did not formulate the inverse square law for gravity.
        • D. Known for quantum theory and the concept of quantized energy levels, not related to the inverse square law of gravity.

        Q83. When the displacement is half the amplitude, the ratio of potential energy to the total energy is:

        • A. 1/2
        • B. 1
        • C. 1/8
        • D. 1/4✓

        Explanation: When displacement is half the amplitude, potential energy is 1/4 of the total energy. This result is derived from the proportional relationship between potential energy and the square of displacement in harmonic motion.

        Why the other options are wrong
        • A. Potential energy is proportional to the square of the displacement, so the ratio changes as explained above.
        • B. Incorrect, it doesn't reflect the change in displacement's impact on energy.
        • C. The potential energy reduction is proportional to the square of the displacement, not the cube.

        Q84. The harmonics which are present in a pipe at one end are:

        • A. Odd harmonics✓
        • B. Even harmonics
        • C. Both odd and even harmonics
        • D. None of these

        Explanation: A closed pipe at one end reflects sound waves, creating nodes at the closed end. This results in odd harmonics (fundamental, 3rd, 5th, etc.).

        Why the other options are wrong
        • B. This option is incorrect due to the pipe's behavior.
        • C. This option is incorrect due to the pipe's behavior.
        • D. Thsi option is incorrect as option A is correct one.

        Q85. Bats invigate and find food by:

        • A. Ultrasonic
        • B. Refraction
        • C. Echolocation✓
        • D. Beats

        Explanation: Bats emit ultrasonic sounds that bounce off objects, allowing them to navigate and locate prey based on sound reflections. They analyze these echoes to perceive their surroundings and find food.

        Why the other options are wrong
        • A. Bats emit high-frequency ultrasonic sounds for echolocation. These sounds bounce off objects, enabling bats to perceive their environment and locate food.
        • B. Refraction is the bending of light as it passes through different mediums. While this is not how bats find food, it is a phenomenon in optics.
        • D. "Beats" could refer to musical beats or rhythmic patterns. It is not related to how bats find food or navigate.

        Q86. Doppler's effect is applicable to:

        • A. Sound waves
        • B. Radio waves
        • C. Electromagnetic waves
        • D. All of these✓

        Explanation: Doppler's effect applies to all options (A, B, C). It describes the change in frequency of waves due to relative motion between the source and observer. For sound, it's apparent in pitch shifts; for radio and electromagnetic waves, in frequency shifts affecting observed wavelength.

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

        Q87. The disadvantage of step_index fibre can be reduced by:

        • A. Graded index fibre✓
        • B. Non graded index fibre
        • C. Both of them
        • D. None of these

        Explanation: The option A is correct. Graded index fibre reduces the disadvantage of step_index fibre by allowing light to travel more efficiently, minimizing dispersion and improving signal quality.

        Why the other options are wrong
        • B. Non graded index fibre does not address the disadvantages of step_index fibre and may still suffer from dispersion and signal degradation.
        • C. This option is incorrect. Only option A (Graded index fibre) effectively reduces the disadvantage of step_index fibre.
        • D. Option A (Graded index fibre) is the correct choice to mitigate the disadvantages of step_index fibre.

        Q88. A charge of 0.10 C accelerated through a potential difference of 1000V acquires kinetic energy:

        • A. 200 J
        • B. 2000 J
        • C. 100 J✓
        • D. 100 eV

        Explanation: The correct option is C. 100 J. The kinetic energy gained by a charge is given by K.E. = q * V, where q is the charge and V is the potential difference.

        Q89. By replacing the dielectrics between the plates of an isolated charged capacitor, the energy stored:

        • A. Remains same✓
        • B. Becomes zero
        • C. Increases
        • D. Decreases

        Explanation: Energy stored depends on charge and voltage. Dielectric change affects voltage and capacitance proportionally, keeping energy constant.

        Why the other options are wrong
        • B. Incorrect, as changing dielectric doesn't discharge the capacitor.
        • C. Incorrect, as dielectric increases capacitance but doesn't alter initial energy.
        • D. Incorrect, as energy depends on capacitance and voltage; altering dielectric affects both, but energy remains constant.

        Q90. The resistance of a wire is 20 ohms, it is stretched so that the length becomes two times, then the new resistance of the wire will be:

        • A. Will become half
        • B. Will be doubled
        • C. Will remain the same
        • D. Will become four times✓

        Explanation: R =ρ L/A When length is doubled the area becomes half. So, R'=ρ 2L/A/2 R' = ρ 4L/A R' = 4(ρ L/A) R' = 4R. Hence, the resistance becomes 4 times.

        Why the other options are wrong
        • A. According to given data, this option is incorrect as explained below.
        • B. According to given data, this option is incorrect as explained below.
        • C. According to given data, this option is incorrect as explained below.

        Q91. Kirchhoff's first rule is a manifestation of law of conservation of:

        • A. Energy
        • B. Charge✓
        • C. Momentum
        • D. K.E

        Explanation: Kirchhoff's first rule, also known as the junction rule, is a manifestation of the law of conservation of charge (B). It states that the sum of currents entering a junction in an electrical circuit is equal to the sum of currents leaving the junction.

        Why the other options are wrong
        • A. Kirchhoff's first rule specifically pertains to the conservation of charge, not energy.
        • C. Kirchhoff's first rule is not related to the conservation of momentum; it's about the conservation of charge in electrical circuits.
        • D. Kirchhoff's first rule doesn't involve kinetic energy; it deals with the conservation of charge in circuits.

        Q92. A charged particle travelling in a uniform field could have a circular trajectory if the field is:

        • A. Gravitational
        • B. Magnetic✓
        • C. Electric
        • D. Gravitational and electric

        Explanation: A charged particle experiences circular motion in a uniform magnetic field due to the Lorentz force.

        Why the other options are wrong
        • A. Gravitational - No circular motion.
        • C. Electric - Radial motion.
        • D. Gravitational and electric - No circular motion.

        Q93. WbA-1 is the unit of:

        • A. Flux density✓
        • B. Mutual inductance
        • C. Self inductance
        • D. Permeability of free space

        Explanation: WbA-1 represents the unit of flux density, which measures the amount of magnetic flux passing through a unit area. It's an essential parameter in electromagnetism.

        Why the other options are wrong
        • B. Mutual inductance measures the ability of two coils to induce voltage in each other. It's measured in henrys (H) and represents the interaction between two magnetic fields.
        • C. Self inductance measures the ability of a coil to induce voltage in itself when the current changes. It's measured in henrys (H) and depends on the coil's geometry.
        • D. The permeability of free space, denoted by μ₀, quantifies how easily magnetic fields can pass through a vacuum. Its unit is H/m and plays a crucial role in electromagnetic theory.

        Q94. Len'z law give:

        • A. The magnitude of the induced e.m.f
        • B. The magnitude of the induced current
        • C. The direction of the induced current✓
        • D. Both the magnitude and direction of induced current

        Explanation: The direction of the induced current is determined by Len's law, which states that the induced current creates a magnetic field opposing the change in the original magnetic field.

        Why the other options are wrong
        • A. The magnitude of the induced emf is determined by Faraday's law of electromagnetic induction.
        • B. The magnitude of the induced current is not given by Lenz law.
        • D. The direction of the induced current is determined by Len's law, which states that the induced current creates a magnetic field opposing the change in the original magnetic field.

        Q95. The solids in which the molecules and ions are arranged in a regular manner called:

        • A. Polymers
        • B. Amorphous
        • C. Crystalline✓
        • D. Glass solid

        Explanation: In crystalline solids, molecules and ions are arranged in a repeating, ordered pattern, giving rise to distinct and well-defined geometric shapes. This arrangement leads to characteristic properties like sharp melting points and regular cleavage planes.

        Why the other options are wrong
        • A. Large molecules made up of repeating subunits, arranged randomly or in a semi-ordered manner. Often have flexible and amorphous structures.
        • B. Lack long-range order, molecules are arranged randomly, resulting in a lack of distinct geometric shapes. Examples include glass and some plastics.
        • D. A type of amorphous solid, lacking a crystalline structure. It has a disordered arrangement of molecules, making it transparent but lacking a definite melting point.

        Q96. A force of 100N can break a wire. The force required to break the wire of double to cross section area is:

        • A. 100 N
        • B. 200 N✓
        • C. 400 N
        • D. 800 N

        Explanation: The force required to break a wire is directly proportional to its cross-sectional area. Doubling the area halves the stress, so 100 N x 2 = 200 N.

        Why the other options are wrong

          Q97. Operational amplifier work with:

          • A. Any feedback
          • B. Positive feedback
          • C. Negative feedback
          • D. Both positive and negative feedback✓

          Explanation: Operational amplifiers can work with both positive and negative feedback. Negative feedback stabilizes and linearizes the amplifier, while positive feedback can lead to oscillations and instability.

          Why the other options are wrong
          • A. Operational amplifier does not work with ANY FEEDBACK. For it's working feedback is must.
          • B. This option is correct.
          • C. This option is correct.

          Q98. A certain force increases the length of a wire by 1mm which of the following is required to increase the length by 2mm:

          • A. 2F
          • B. 4F✓
          • C. 8F
          • D. 16F

          Explanation: Doubling the elongation requires four times the force.

          Why the other options are wrong
          • A. Option A (2F) would likely result in less than 2mm elongation.
          • C. Option C (8F) and D (16F) would excessively stretch the wire beyond 2mm.
          • D. Option C (8F) and D (16F) would excessively stretch the wire beyond 2mm.

          Q99. As the quantum number increases, the energy difference between the consecutive energy levels of an atom:

          • A. Increases
          • B. Decreases✓
          • C. Remains same
          • D. Becomes infinite

          Explanation: As the quantum number increases, the energy difference between consecutive energy levels of an atom decreases. This is a consequence of the quantization of energy levels in atoms, described by the Bohr model and later refined by quantum mechanics. As you move to higher quantum numbers (e.g., from n=1 to n=2, n=2 to n=3, and so on), the energy levels become closer together, and the energy difference between them becomes smaller. This is why spectral lines in atomic spectra appear closer together at higher energy levels.

          Why the other options are wrong
          • A. This option suggests that as the quantum number (n) increases, the energy difference between consecutive energy levels of an atom increases. However, this is not the case. In reality, as the quantum number increases, the energy difference between consecutive energy levels decreases. This is a fundamental feature of atomic energy levels in the Bohr model.
          • C. This option implies that the energy difference between energy levels does not change as the quantum number increases. This is not correct; the energy levels are quantized, and the energy difference between them decreases with increasing quantum number.
          • D. This option suggests that as the quantum number increases, the energy difference between energy levels becomes infinitely large. This is not accurate; in reality, the energy difference approaches zero as you move to higher quantum numbers, but it never becomes infinite.

          Q100. The particles with mass less than of protons (among Hadrons) are called:

          • A. Baryons
          • B. Mesons✓
          • C. Quarks
          • D. Leptons

          Explanation: The particles with mass less than that of protons among Hadrons are called Mesons. Mesons are composed of a quark and an antiquark, making them lighter than baryons like protons and neutrons.

          Why the other options are wrong
          • A. Baryons are heavier particles consisting of 3 quarks.
          • C. Quarks are elementary constituents of hadrons.
          • D. Leptons are light, elementary particles unaffected by strong nuclear force.

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