Kpk Mdcat Mock Paper 2 — Solved Past Paper with Answers

Q1. Antonym of Atheist will be:

• A. Hypnotic
• B. Bane
• C. Believer✓
• D. Theorist

Explanation: Atheist means someone who denies or disbelieves in the existence of god. A believer is the perfect opposite of an atheist.

Q2. Select the nearest correct meaning of the given word:FROWSY

• A. Disheveled✓
• B. Arranged
• C. Drowsy
• D. Bluish

Explanation: Dishelved means unkempt, untidy, or dirty. It is the closest in meaning to frowsy because it describes a person or thing that is not well-groomed or that is in a state of disarray.

Q3. Complete the sentences by choosing the most appropriate option, from the given lettered choices below. We must _ back by six o’clock.

• A. Be✓
• B. Can
• C. Has
• D. Have

Explanation: The sentence requires a word that fits grammatically and logically in the expression 'must _ back by six o’clock.' The correct choice is 'be' because 'must be back' is a standard expression indicating an obligation or necessity to return by a specified time. The other options ('can,' 'has,' 'have') do not form correct or meaningful expressions in this context.

Q4. Each sentence below has a blank indicating that something has been omitted. Choose the word that best fits in with the meaning of the sentence as a whole.The sunlight shining through the branches made a _ pattern on the tiles.

• A. Angina
• B. Basilica
• C. Filigree✓
• D. Corollary

Explanation: Filigree refers to an intricate, delicate, and often lace-like design, which can describe the complex and detailed pattern of light and shadow created by sunlight filtering through branches.

Q5. In the following question, four alternative sentences are given. Choose the CORRECT option.

• A. After breaking the glass, Ruby said "Please don't tell on me".
• B. After breaking the glass Ruby said: "Please don't tell on me."
• C. After breaking the glass, Ruby said: "Please don't tell on me."✓
• D. After breaking the glass Ruby said: please don't tell on me.

Explanation: The sentence 'after breaking the glass' is another idea in the sentence hence a comma should be added between these two sentences. The rule of punctuation in quotation marks is that the full stop or comma should come within the quotation marks.'Don't' is a contraction, which stands for 'do not'.

Q6. Use an appropriate article:I lived on _ Main Street when I first came to town.

• A. A
• B. An
• C. The
• D. No article is required✓

Explanation: In general, We usually don’t use an article with the names of most streets, roads, avenues, boulevards, etc. Moreover, no article is used with proper nouns, mass nouns where the reference is indefinite, or plural countable nouns where the reference is indefinite.

Q7. My father _ us popcorn and orange juice.

• A. Buy
• B. Will buy
• C. Bought✓
• D. Have bought

Explanation: The verb "bought" is in the past tense and indicates that the action of buying has already been completed in the past.

Q8. It’s raining cats and dogs. So there are _ cars on the road today.

• A. Few✓
• B. A few
• C. A big number of
• D. A great deal of

Explanation: The phrase 'It's raining cats and dogs' suggests heavy rain, which typically leads to fewer cars on the road. The correct word is 'few', which implies 'not many cars.' The phrase 'a few' would suggest some cars, which doesn't emphasize the reduction in number. 'A big number of' and 'a great deal of' imply a large quantity, which contradicts the expected decrease in car numbers due to the rain.

Q9. ‘To the letter’ means:

• A. Cursory
• B. Enveloping a letter
• C. Precisely✓
• D. Reporting a problem

Explanation: "To the letter" means adherence to every detail or precision.

Q10. The cell wall of most of the bacteria have a unique macromolecule called_.

• A. Cellulose
• B. Chitin
• C. Fibres
• D. Fats
• E. Peptidoglycan✓

Explanation: A cell wall is a layer located outside the cell membrane found in plants, fungi, bacteria. Plant cell is made up of cellulose, fungi cell of chitin and bacteria cell is made up of peptidoglycan.

Q11. Which is distributed more widely in a cell?

• A. DNA
• B. RNA✓
• C. Chloroplasts
• D. Phagosomes

Explanation: RNA (ribonucleic acid) is distributed more widely in a cell compared to DNA (deoxyribonucleic acid). While DNA is primarily found in the nucleus of eukaryotic cells and in the nucleoid region of prokaryotic cells, RNA is present throughout the cell, including the nucleus, cytoplasm, and various organelles.RNA plays a crucial role in protein synthesis as it carries the genetic information from DNA to the ribosomes, where proteins are synthesized. There are different types of RNA molecules, such as messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each with specific functions in protein synthesis

Q12. Most abundant carbohydrate in nature is:

• A. Cellulose✓
• B. Polysaccharides
• C. Starch
• D. Glycogen

Explanation: Cellulose is the most abundant carbohydrate in nature, serving as a crucial structural component in plant cell walls. Its abundance is due to the extensive presence of plants on Earth. In contrast, polysaccharides like starch and glycogen are primarily involved in energy storage and are not as pervasive as cellulose. Starch is typically found in plant storage tissues, while glycogen is specific to animal cells, which limits their abundance compared to cellulose.

Q13. How many water molecules will be released upon the formation of a trisaccharide?

• A. 1
• B. 2✓
• C. 3
• D. 4

Explanation: To form a trisaccharide, three monosaccharides are linked together. Each link between two monosaccharides is a glycosidic bond, which releases one water molecule. Thus, two glycosidic bonds are formed to link three monosaccharides, releasing two water molecules in total. Option B is correct because it reflects the correct number of water molecules released during this process. Options A, C, and D are incorrect because they represent the number of water molecules released when forming disaccharides, tetrasaccharides, and pentasaccharides, respectively.

Q14. A powerful digesting enzyme that is capable of destroying a cell's internal structure is called _

• A. Lipase
• B. DNase
• C. Phospholipase✓
• D. Both B and C

Explanation: The correct answer is C: Phospholipase. Phospholipase enzymes break down phospholipids, which are critical components of cell membranes. By disrupting the membrane, phospholipases can compromise the integrity of the cell's structure, potentially leading to cell lysis. Lipase, on the other hand, targets fats for digestion outside of the cellular context. DNase digests DNA, which can affect genetic material but not the structural integrity of the cell as a whole. Option D, B and C, is incorrect because DNase does not disrupt the cell membrane.

Q15. Lungs do not collapse between breaths, and some air always remains in the lungs, which can never be expelled because:

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

Explanation: Option B is correct.All options are explained below:a)There is a negative pressure in the lungs."This statement is not entirely accurate. Lungs don't naturally have a negative pressure, and they can't be filled with air if there is a consistent negative pressure. Lungs maintain a degree of positive pressure to keep them expanded.b) "There is a negative intrapleural pressure pulling at the lung walls": This option is correct. Between breaths, the lungs do not collapse due to the presence of a negative intrapleural pressure. Intrapleural pressure is the pressure in the pleural cavity, which surrounds the lungs. It is typically lower than atmospheric pressure, creating a "suction" effect that keeps the lungs inflated. This is a key mechanism for lung expansion and prevents lung collapse.c)"There is a positive intrapleural pressure": This statement is not accurate. A positive intrapleural pressure would not be conducive to maintaining lung expansion; it's the negative intrapleural pressure that plays a critical role in preventing lung collapse.d)"Pressure in the lungs is higher than the atmospheric pressure": This is not correct. The pressure in the lungs, during exhalation, is generally close to atmospheric pressure, but it's the intrapleural pressure that is negative, not the pressure in the lungs themselves.Summary: The correct answer is: "There is a negative intrapleural pressure pulling at the lung walls." The negative intrapleural pressure, which is lower than atmospheric pressure, keeps the lungs expanded by exerting a suction effect on the lung walls, preventing lung collapse between breaths.

Q16. Which of these enzymes works best at a pH of 2.00?

• A. Sucrase
• B. Salivary enzymes
• C. Pepsin✓
• D. Enterokinase

Explanation: Pepsin is a digestive enzyme secreted by the stomach to help break down proteins. It works best in highly acidic conditions, with an optimal pH of around 2.00. The stomach provides this environment, as its pH typically ranges from 1.5 to 2.5. This low pH allows pepsin to function effectively and carry out its role in protein digestion.

Q17. Which one of the following cell organelles is enclosed by a single membrane?

• A. Lysosomes✓
• B. Nucleus
• C. Mitochondria
• D. Chloroplasts

Explanation: Lysosomes are enclosed by a single membrane and contain hydrolytic enzymes that help in digestion processes within the cell.

Q18. The nuclear envelope is a derivative of:

• A. Microtubules
• B. Rough endoplasmic reticulum✓
• C. Smooth endoplasmic reticulum
• D. Membrane of Golgi complex

Explanation: The rough endoplasmic reticulum (RER) is directly involved in the formation of the nuclear envelope. During cell division, the nuclear envelope disintegrates, and its components are absorbed into the RER. After division, the RER helps in reassembling the nuclear envelope, making it a derivative of the RER.

Q19. Tobacco mosaic virus (TMV) genes are:

• A. Single stranded RNA✓
• B. Double stranded DNA
• C. Proteinaceous
• D. Double stranded RNA

Explanation: The correct answer is a) single-stranded RNA. The genes of the tobacco mosaic virus (TMV) are composed of single-stranded RNA. This RNA genome contains the instructions for the virus to infect host plant cells, replicate, and produce new viral particles, leading to the characteristic mosaic-like patterns and other symptoms observed in infected plants.

Q20. Which of the following statements about enzymes is false?

• A. The Keq of a reaction remains unchanged in the presence of an enzyme.
• B. Enzymes speed up the rate of reaction in DNA synthesis.
• C. Harsh, acidic conditions can completely denature an enzyme.
• D. An enzyme is completely converted to product during metabolism.✓

Explanation: Enzymes are not consumed or completely converted to products during metabolism. Enzymes are catalysts that facilitate and accelerate biochemical reactions without being consumed or altered in the process. They remain unchanged after the reaction and are available to catalyze additional rounds of the same reaction.

Q21. The ability to distinguish between two separate points/objects is:

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

Explanation: The correct answer is Resolution. Resolution is a key concept in microscopy and imaging, as it defines the ability to distinguish between two closely positioned objects as separate entities. This clarity is essential for detailed analysis in cell biology.While Magnification increases the size of the image, it does not enhance clarity or detail necessary for resolving two close points. Fractionation and Centrifugation are techniques related to separating components of mixtures based on size or density, and do not pertain to the optical resolution of images.

Q22. Hypothalamus connected to pituitary gland via:

• A. Nerves
• B. Infundibulum✓
• C. Blood
• D. No connection

Explanation: The hypothalamus is connected to the pituitary gland via the infundibulum, which is a funnel-shaped structure that physically links the two. This connection allows the hypothalamus to regulate the pituitary gland's hormone secretion. The other options are incorrect as nerves, blood, or no connection do not directly link these two structures in the central nervous system.

Q23. The enzyme which is found in saliva accelerates the conversion of starch into sugar is:

• A. Pepsin
• B. Thrombin
• C. Ptyalin✓
• D. Fumarase

Explanation: Ptyalin is a form of amylase found in the saliva of humans and some other animals. The ptyalin enzyme breaks down the carbohydrates into simple sugars, which the body can absorb.

Q24. ELISA is used to detect viruses where the key reagent is:

• A. Alkaline phosphatase✓
• B. Catalase
• C. DNA probe
• D. RNAase.

Explanation: ELISA (enzyme linked immunosorbent assay) screening test is the initial test to diagnose AIDS. The test works by detecting antibodies/ substances or protein which are produced in the blood when the virus is present.Alkaline phosphatase and peroxidases are commonly used enzymes as key reagents to perform the ELISA test. These enzymes are used to provide antibody-­antigen complex in a specialized ELISA plate or tray. In ELISA test for detecting a particular antigen, its antibody is buffered and a drop of serum (supernatant of centrifuged blood) is poured over it. If the latter contains antigen, it will produceantigen­ antibody complex. A second enzyme labelled antibody is added. It forms an enzyme­antigen­ antibody complex if the antigen is present. The substrate is now added. It produces a stain if the antigen is present.

Q25. Name the chronic respiratory disorder caused mainly by cigarette smoking.

• A. Respiratory acidosis
• B. Respiratory alkalosis
• C. Emphysema✓
• D. Asthma

Explanation: Emphysema is a chronic respiratory disorder primarily caused by cigarette smoking, leading to damaged lung tissue and breathing difficulties.

Q26. Find mismatch

• A. Thyroid gland-T3 and T4
• B. Parathyroid gland-Calcitonin✓
• C. Pancreas-Insulin
• D. Gonads-Testes and ovaries

Explanation: The correct answer is Option B: 'Parathyroid gland-Calcitonin'. This is a mismatch because the parathyroid glands produce parathyroid hormone (PTH), not calcitonin. Calcitonin is produced by the thyroid gland and works to reduce blood calcium levels, counteracting PTH. The other options correctly match the glands with their primary hormones or functions: the thyroid produces T3 and T4, the pancreas produces insulin, and the gonads refer to testes and ovaries in the reproductive system.

Q27. To the end of the first trimesters, the embryo can now technically describe as a:

• A. Zygote
• B. Infant
• C. Toddler
• D. Fetus✓

Explanation: At the conclusion of the first trimester, the embryo undergoes significant development and is officially termed a fetus. This transition marks the end of the embryonic stage, as critical structures have begun forming, preparing for further growth and development. Other options such as zygote, infant, and toddler refer to different stages of development, either too early in pregnancy or post-birth, making them incorrect in this context.

Q28. In heavy smokers the alveoli become enlarged and damaged which reduces the surface area for the exchange of respiratory gases.This condition is called:

• A. Lung cancer
• B. Emphysema✓
• C. Asthma
• D. Bronchitis

Explanation: Emphysema is a chronic respiratory condition often caused by smoking, where the alveoli in the lungs are destroyed and enlarged. This damage leads to a reduction in the surface area available for the exchange of oxygen and carbon dioxide, resulting in breathing difficulties. Unlike emphysema, lung cancer involves the uncontrolled growth of abnormal cells in lung tissues, asthma involves airway inflammation and narrowing, and bronchitis involves inflammation of the bronchial tubes, none of which primarily involve the destruction of alveoli.

Q29. Recombinants contains DNA from

• A. Two different sources✓
• B. A single source
• C. Two identical sources
• D. Three identical sources

Explanation: Recombinant DNA technology is the process of joining together DNA from two different species, resulting in a new genetic combination that can be used in various fields such as science, medicine, agriculture, and industry. The key aspect is that the DNA must come from two distinct sources to create the recombinant DNA molecule. Options B, C, and D are incorrect because they involve DNA from the same source or multiple identical sources, which does not meet the criteria for recombination.

Q30. It is possible to insert a foreign DNA into an animal egg by:

• A. Manual microinjection
• B. Vortex mixing
• C. Manual microinjection or vortex mixing✓
• D. Using electric current

Explanation: These are two available methods to insert a desired gene into an animal egg.

Q31. The animals which eat both plant and animal foods are called

• A. Filter feeders
• B. Omnivores✓
• C. Fluid feeders
• D. Macrophagus feeders

Explanation: A. Many aquatic animals filter the water and digest the particles that they extract from itC. When food in ingested in liquid formsD. Animals which take food in the form of large pieces are microphagous feeders

Q32. Uricotelic mode of excreting nitrogenous wastes is found in:

• A. Reptiles and birds✓
• B. Birds and annelids
• C. Amphibians and reptiles
• D. Insects and amphibians

Explanation: The correct answer is Reptiles and birds. These animals are uricotelic, meaning they excrete nitrogenous wastes as uric acid, which is advantageous in conserving water due to its low solubility. This adaptation is particularly beneficial for survival in arid and water-scarce environments. On the other hand, while insects also excrete uric acid, amphibians usually excrete urea or ammonia, reflecting their more aquatic lifestyles. Annelids excrete ammonia or urea, not uric acid, which is why options involving these animals are incorrect.

Q33. Expiratory centre in medulla is:

• A. Dorsal✓
• B. Ventral
• C. Lower part
• D. All of the above

Explanation: The dorsal and lateral regions contain the expiratory centre, they stimulate expiration and inhibit inspiration.

Q34. When the sperm count is high, inhibin hormone release increases which:

• A. Inhibits anterior pituitary release follicle stimulating g hormone✓
• B. Increase anterior pituitary release of follicle stimulating hormone
• C. Inhibit release of luteinizing hormone
• D. Increaserelease of luteinizing hormoneave

Explanation: When the sperm count exceeds set limits,The hormone inhibits GnRH and FSH, decreasing the activity of the Sertoli cells. It inhibits the synthesis and release of the follicle-stimulating hormone in the pituitary gland and reduces the hypothalamic LH - releasing hormone content.

Q35. In the intestine, amino acids are absorbed by?

• A. None of these
• B. Capillaries✓
• C. Lacteals
• D. Both of these

Explanation: Amino acids, being water-soluble like most of the other nutrients, are absorbed by capillaries of the villus of the small intestine. The fats and fat-soluble vitamins, however, are absorbed by the lacteals.

Q36. Lock and Key Model for enzyme action propose by Emil Fischer suggests that:

• A. Enzymes are unbiased for the substrate
• B. Enzymes can modify their active sites
• C. Enzymes are restricted to one reaction type✓
• D. An enzyme can catalyze variety of reactions

Explanation: The lock and key mechanism is a metaphor to explain the specificity of the enzyme's active site and the substrate. Similar to how only a certain key fits a lock, only certain substrates can fit an enzyme's active site. When the correct substrate binds to the enzyme's active site, an Enzyme substrate complex is formed. This simply means that only one type of substrate can be acted upon by an enzyme. The statement C implies that since only one type of substrate can fit into the active site of an enzyme, the type of reaction either being catabolic or anabolic in nature is also dependent on the active site of the enzyme and the type of substrate. To further explain, consider an example of an enzyme A acting on a substrate A in a catabolic reaction. It would only be able to catalyze the catabolic reaction and not any other type of reaction such as anabolic reaction on that particular substrate. A and D, on the other hand, are the exact opposite of the above statements as enzymes are specific for the substrate.

Q37. In tissue culture medium, the embryoids formed from pollen grains is due to :

• A. Cellular totipotency✓
• B. organogenesis
• C. Double fertilization
• D. Test tube culture.

Explanation: Totipotency refers to the capacity of each living cell of a multicellular organism being capable of independent development when provided with suitable conditions. Guha and Maheshwari (1966) cultured anthers of Datura. The haploid pollen grain inside the anther divides to form a multicellular mass of cells called callus. Using varying quantities of auxins and cytokinins in the culture medium, this callus is differentiated into embryoids which later germinates to form the entire plant.

Q38. Most enzymes have an optimum temperature of around:

• A. 30°C
• B. 40°C✓
• C. 50°C
• D. 20°C

Explanation: Most enzymes have an optimum temperature at which they function most efficiently. For many enzymes in the human body, this optimum temperature is around 37 degrees Celsius (98.6 degrees Fahrenheit), which is the normal body temperature. However, the specific optimum temperature can vary for different enzymes. Hence here we will select 40 degrees Celsius.

Q39. 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.

Q40. DNA polymerase copies the target DNA, after the:

• A. Primers bind by complementary base pairing✓
• B. The target DNA duplex is unwound
• C. The target DNA gets denatured
• D. The primers get separated from target DNA

Explanation: In PCR both strands of DNA act as template for new strands to be synthesized.

Q41. If the patient dies due to numerous infections of the respiratory tract, it means he/she suffered from:

• A. SCIDS
• B. Cystic fibrosis✓
• C. Hypercholesterolemia
• D. Parkinsonism

Explanation: Cystic fibrosis patients lack a gene that codes for trans-membrane carrier of chloride ions.

Q42. The deficiency of which of the following causes severe combined immunodeficiency?

• A. Hypoxanthine-guanine transferase
• B. Xanthine oxidase
• C. PRPP synthetase
• D. Adenosine deaminase✓

Explanation: ADA deficiency leads to SCID, a group of rare, inherited disorders characterized by a severe impairment of both the T and B lymphocytes of the immune system. Adenosine deaminase is involved in the breakdown of purines, and its deficiency results in the accumulation of toxic metabolites. that are particularly harmful to developing immune cells.

Q43. Cholesterol is:

• A. Animal sterol
• B. C27H46O
• C. Have 5 methyl groups
• D. All of these✓

Explanation: Cholestrol is an animal sterol which the structure shown below indicating the presence of 5 methyl groups and the molecular formula C27H46O.

Q44. Reverse transcriptase is a useful enzyme to have when:

• A. RNA virus converts its RNA to DNA✓
• B. There are no host cells present
• C. Nutrients are scarce
• D. Spikes are forming in the new virus

Explanation: Reverse transcriptase is an enzyme that allows the conversion of RNA into DNA. It is commonly found in retroviruses, such as HIV, where it plays a crucial role in the replication of the viral genome. By converting the viral RNA into DNA, the virus is able to integrate its genetic material into the host cell's DNA and hijack the host's cellular machinery to produce new virus particles. Reverse transcriptase is also used in molecular biology research, such as in the polymerase chain reaction (PCR) technique.

Q45. An enzyme that cleaves a DNA duplex molecule, at a particular base sequence, usually within or near a palindromic sequence, is called:

• A. Polymerase
• B. Helicase
• C. Restriction endonuclease✓
• D. Ligase

Explanation: The correct answer is restriction endonuclease. These enzymes are crucial in biotechnology for their ability to recognize and cleave DNA at specific sequences, often palindromic. This property allows scientists to cut DNA in a controlled manner for cloning and analysis. In contrast, polymerase synthesizes DNA, helicase unwinds DNA, and ligase joins DNA fragments. None of these other enzymes is involved in cutting DNA at specific sequences.

Q46. Two species can avoid competition and better use the environment's resources by occupying different:

• A. Adaptations
• B. Polymorphism
• C. Niches✓
• D. Specialization

Explanation: The correct answer is niches. A niche encompasses the role a species plays in its ecosystem, including how it acquires resources, survives, and reproduces. By occupying different niches, species can coexist in the same environment without direct competition, allowing each to exploit different resources and conditions effectively.Adaptations are about traits enhancing survival and reproduction but do not specifically address interspecies competition. Polymorphism refers to genetic diversity within a species and does not relate to the interaction between species. Specialization allows species to focus on specific roles, but it is more about within-species adaptation rather than interspecific niche differentiation.

Q47. How many ml of oxygen are present in a litre of water?

• A. 10✓
• B. 20
• C. 40
• D. 200

Explanation: Under typical conditions, the solubility of oxygen in water is approximately 8 milligrams per liter (mg/L) or 8 parts per million (ppm). To convert the concentration of dissolved oxygen from milligrams per liter (mg/L) to milliliters per liter (ml/L), we need to consider that 1 milligram is equal to 1 cubic centimeter (cc) or 1 milliliter (ml). Therefore, 8 mg/L is equal to 8 ml/L of dissolved oxygen which is approximately equal to 10 ml.

Q48. Which of the following combination is an example of self-replicating organelles?

• A. Mitochondria and Ribosomes
• B. Mitochondria and Chloroplasts✓
• C. Mitochondria and Vacuoles
• D. Mitochondria and Lysosomes

Explanation: The correct answer is Option B: Mitochondria and Chloroplasts. These organelles are unique because they contain their own DNA and can replicate independently of the cell's main genome. This feature is consistent with the endosymbiotic theory, suggesting that mitochondria and chloroplasts originated from ancient symbiotic bacteria. In contrast, ribosomes are complex molecular machines assembled in the nucleolus, vacuoles function as storage compartments without genetic material, and lysosomes are produced by the Golgi apparatus without possessing their own DNA or self-replicating ability.

Q49. After coming out of the capsule as efferent arteriole, the blood vessel subdivides again into another network of capillaries called :

• A. Vasa Recta
• B. Afferent Arteriole
• C. Peritubular Capillaries✓
• D. Renal Vein

Explanation: Peritubular capillaries constitute a network of tiny blood vessels that travel alongside nephrons, allowing reabsorption and secretion between blood and the inner lumen of the nephron. Peritubular capillaries surround the proximal and distal tubules, as well as the loop of Henle where they are known as Vasa recta.

Q50. What will happen if the stretch receptors of the urinary bladder wall are totally removed?

• A. Micturition will continue
• B. Urine will continue to collect normally in the bladder
• C. There will be no micturition✓
• D. Urine will not collect in the bladder

Explanation: The stretch receptors in the urinary bladder wall detect when the bladder is full by sensing the pressure of the urine. This triggers the micturition reflex, which involves the autonomic nervous system and leads to the expulsion of urine. If these receptors are removed, the reflex cannot be initiated, and micturition will not occur. Option C is correct as it states that there will be no micturition. Option A is incorrect because without the reflex, micturition cannot continue. Option B is misleading as it suggests normal urine collection but does not address the absence of the micturition reflex. Option D is incorrect because urine production and collection in the bladder are separate from the presence of stretch receptors.

Q51. The breakdown of glucose in a cell yields pyruvate in the:

• A. Presence of oxygen
• B. Absence of oxygen
• C. Presence or absence of oxygen✓
• D. High concentration of oxygen

Explanation: The correct answer is option C: presence or absence of oxygen. Glycolysis is the initial process in glucose metabolism, converting glucose into pyruvate within the cytoplasm, regardless of oxygen presence. It is considered an anaerobic process since it doesn't require oxygen. Under aerobic conditions, pyruvate is further oxidized in the mitochondria, while under anaerobic conditions, it is converted into lactic acid or ethanol. Options A and B are incorrect, as they each consider only one condition, while option D is incorrect, as glycolysis is not affected by oxygen concentration.

Q52. Which cartilage is present at the end of long bones?

• A. Fibrous cartilage
• B. Hyaline cartilage✓
• C. Elastic cartilage
• D. Calcified cartilage

Explanation: Articular cartilage at the ends of long bones is hyaline cartilage, reducing friction in joints.

Q53. The repeated protein pattern of myofibrils is called:

• A. Sarcomere✓
• B. Sarcolemma
• C. Zyomere
• D. Cross bridges

Explanation: The correct answer is the sarcomere, which is the repeating unit within myofibrils responsible for muscle contraction. Sarcomeres contain actin and myosin filaments that slide past each other to facilitate contraction. The sarcolemma is the muscle cell membrane and not part of the repeating protein pattern. Zygomere is not a valid term in muscle anatomy. Cross bridges are temporary structures formed during contraction, not the repeating pattern within myofibrils.

Q54. Smooth endoplasmic reticulum is similar in structure to:

• A. RER
• B. Golgi bodies
• C. Microfilaments
• D. Sarcoplasmic reticulum✓

Explanation: The sarcoplasmic reticulum is a specialized type of smooth endoplasmic reticulum found in muscle cells. Its main function is to store and release calcium ions, which are critical for initiating and regulating muscle contraction. When a muscle fiber is stimulated, calcium is released from the sarcoplasmic reticulum, binding to troponin and allowing actin and myosin interactions to occur, leading to muscle contraction. The other options: RER, Golgi bodies, and microfilaments do not perform the same function. RER is involved in protein synthesis, Golgi bodies are involved in modifying and packaging proteins, and microfilaments are structural components, none of which directly relate to the function of the sarcoplasmic reticulum in muscle contraction.

Q55. About 55% of the volume of human blood is:

• A. Plasma✓
• B. Blood cells
• C. Blood Protein
• D. A and B

Explanation: About 55% of the volume of human blood is plasma. Plasma is the liquid component of blood that makes up the majority of its volume. It contains water, electrolytes, hormones, waste products, and various proteins.

Q56. Which one of the following gives rise to macrophages?

• A. Neutrophils
• B. Eosinophils
• C. Monocytes✓
• D. Lymphocytes

Explanation: Monocytes have a relatively longer lifespan and employ a more intensive approach to killing pathogens compared to neutrophils. They are also able to give rise to macrophages, hence it is the correct option.

Q57. The T-lymphocytes and B-lymphocytes are the major cells of the:

• A. Thymus
• B. Lymph nodes✓
• C. Adrenal glands
• D. Lymphatic vessels

Explanation: Lymph nodes house large populations of B and T lymphocytes for immune defense.

Q58. The antigen-antibody complexes formed in the body are taken up by:

• A. Phagocytes✓
• B. Lymphocytes
• C. Monocytes
• D. Leukocytes

Explanation: Phagocytes, such as neutrophils and macrophages, are crucial for the immune system's function of engulfing and digesting foreign particles, including antigen-antibody complexes. These cells are equipped to identify and internalize these complexes, aiding in their removal from the body. While lymphocytes are vital for recognizing antigens and initiating immune responses, they do not perform phagocytosis. Monocytes can differentiate into macrophages, which are phagocytic, but the term 'monocytes' itself does not directly imply phagocytic activity. Leukocytes encompass a broader category of white blood cells, not all of which are phagocytic.

Q59. About which day in a normal human menstrual cycle does rapid secretion of LH (popularly called LH surge) normally occurs?

• A. 14th day✓
• B. 20th day
• C. 5th day
• D. 11th day

Explanation: The correct option (a) 14th day: In a normal human menstrual cycle, the rapid secretion of luteinizing hormone (LH) typically occurs around the 14th day. This surge in LH is also known as the LH surge and is a key event in the menstrual cycle. The LH surge triggers ovulation, which is the release of an egg from the ovary. Following the LH surge, the egg can be fertilized by sperm if sexual intercourse takes place around this time.

Q60. Which one of the following statements in regard to the excretion by the human kidneys is correct?

• A. Descending limb of loop of Henle is impermeable to water
• B. Distal convoluted tubule is incapable of reabsorbing HCO3-
• C. Nearly 99% of the glomerular filtrate is reabsorbed by the renal tubules✓
• D. Ascending limb of loop of Henle is impermeable to electrolytes.

Explanation: Urine formation involves three main processes, namely, glomerular filtration, reabsorption, and secretion, that take place in different parts of the nephron. A comparison of the volume of the filtrate formed per day (180 litres per day) with that of the urine released (1.5 litres) suggests that nearly 99 percent of the filtrate is reabsorbed by the renal tubules. The descending limb of the loop of Henle is permeable to water but almost impermeable to electrolytes. The ascending limb is impermeable to water but allows transport of electrolytes actively or passively. Conditional reabsorption of Na+ + and water takes place in the distal convoluted tubule. It is also capable of reabsorption of HCO3–.

Q61. Concentration of urine depends upon which organ?

• A. Bowman’s capsule
• B. Length of loop of Henle✓
• C. Proximal Convoluted Tubule (PCT)
• D. Network of capillaries arising from glomerulus

Explanation: Concentration of urine depends upon the length of Henle’s loop. Loop of Henle is the hairpin shaped section of a kidney tubule situated between the proximal and distal tubules in the nephron. It consists of a thin descending limb which is permeable to water and a thick ascending limb which is impermeable to water complex movements of ions and water across the walls of the loop enable it to function as a countercurrent multiplier, resulting in the production of concentrated urine in the collecting duct.

Q62. Freshly released human egg has:

• A. One Y chromosome
• B. One X chromosome✓
• C. Two X chromosomes
• D. One X ­chromosome and one Y­ chromosome

Explanation: A freshly released human egg, also known as an oocyte, contains half of the genetic material required for the formation of a new individual. To be specific, it contains 23 chromosomes. However, all of these chromosomes are from the X chromosome group. There are no Y chromosomes in a freshly released human egg. This is because the egg always carries an X chromosome, while the sex of the resulting individual (male or female) is determined by the sperm cell that fertilizes the egg.Now, let's explain each of the options:a. One Y chromosome: This option is incorrect. There is no Y chromosome present in a freshly released human egg.b. One X chromosome: This option is correct. A freshly released human egg does indeed have one X chromosome.c. Two X chromosomes: This option is incorrect. A freshly released human egg only contains one X chromosome.d. One X chromosome and one Y chromosome: This option is incorrect. As mentioned earlier, the egg only contains one X chromosome, and the Y chromosome is not present in the egg.Correct answer: b. One X chromosomeSummary: A freshly released human egg has one X chromosome. The presence of the Y chromosome or the determination of the individual's sex (male or female) is determined by the sperm cell that fertilizes the egg. The egg always contributes an X chromosome, and the sperm can contribute either an X or a Y chromosome, resulting in the genetic sex of the offspring.

Q63. The tubular epithelium also secretes substances into the lumen, which is mainly of :

• A. Hydrogen Ions✓
• B. Hydroxyl Ions
• C. Potassium Ions
• D. Sodium Ions

Explanation: The correct answer is Hydrogen Ions. The tubular epithelium of the kidney plays a crucial role in acid-base balance by secreting hydrogen ions into the lumen, which helps maintain the pH of the blood and urine. This secretion is vital for excreting excess acid and maintaining homeostasis. Other ions like hydroxyl, potassium, and sodium have different primary functions in the body: hydroxyl ions are involved in making solutions basic, potassium ions are mainly involved in electrical signaling and fluid balance, and sodium ions are critical for fluid balance and blood pressure regulation.

Q64. The human embryo remains enclosed in:

• A. Amniotic sac✓
• B. Placenta
• C. Chorion
• D. Allantois

Explanation: The human embryo remains enclosed in the amniotic sac, a fluid-filled membrane that provides protection and a stable environment for development. The sac is filled with amniotic fluid, which cushions the embryo against mechanical shocks, prevents dehydration, and allows free movement essential for proper growth. The amniotic sac, along with the placenta and umbilical cord, plays a crucial role in supporting the embryo throughout pregnancy by facilitating nutrient exchange and waste removal while safeguarding it from external harm.

Q65. The surgical transplantation of a matching donor's kidney is the only option left for the permanent treatment of :

• A. Kidney Stones
• B. Hypercalcemia
• C. Uremia✓
• D. Hyperoxaluria

Explanation: Uremia results from end-stage kidney failure, where waste products accumulate in the blood due to severely impaired kidney function. Permanent treatment often requires dialysis or a kidney transplant, making transplantation the only option for a long-term solution.

Q66. Thalassemia and sickle cell anemia are caused due to a problem in globin molecule synthesis. Select the correct statement:

• A. Both are due to a quantitative defect in globin chain synthesis
• B. Thalassemia is due to less synthesis of globin molecules✓
• C. Sickle cell anemia is due to a quantitative problem of globin molecules
• D. Both are due to a qualitative defect in globin chain synthesis

Explanation: Sickle cell anemia is caused by a point mutation at the 6th position of the beta-globin chain, where glutamic acid is replaced by valine, leading to a qualitative defect in hemoglobin function. In contrast, thalassemia is characterized by mutations or deletions that reduce the synthesis of one of the globin chains, a quantitative defect. Thus, the correct statement is that thalassemia involves less synthesis of globin molecules, a quantitative issue, while sickle cell anemia involves a qualitative change.

Q67. A normal-­visioned man whose father was colour­-blind marries a woman whose father was also colour-­blind. They have their first child as a daughter. What are the chances that this child would be colour­-blind?

• A. 100%
• B. 0 %✓
• C. 25%
• D. 50%

Explanation: Color blindness is an X-linked recessive trait. The father, who is normal-visioned, has an X chromosome with the normal vision allele (XN) and a Y chromosome. The mother, being a carrier due to her color-blind father, has one XN and one Xc. Their daughter inherits XN from her father and either XN or Xc from her mother. Therefore, she will be either normal (XNXN) or a carrier (XNXc), but not color-blind, as she doesn't inherit two Xc alleles. This makes the chance of her being color-blind 0%. The other options are incorrect because they do not accurately represent the genetic inheritance pattern for this X-linked trait.

Q68. A test cross is carried out to:

• A. Determine the genotype of a plant at F2✓
• B. Predict whether two traits are linked
• C. Assess the number of alleles of a gene
• D. Determine whether two species or varieties will breed successfully or not

Explanation: A test cross is performed to determine the genotype of the F2 plant. In a typical test cross, an organism showing dominant phenotype and whose genotype is to be determined is crossed with one that is homozygous recessive for the allele being investigated, instead of self­crossing. The progenies of such a cross can easily be analyzed to predict the genotype of the test organism. Given ahead is an illustration of a test cross:

Q69. Which one of the following conditions correctly describes the manner of determining the sex?

• A. Homozygous sex chromosomes (ZZ) determine female sex in birds
• B. XO type of sex chromosomes determine male sex in grasshoppers✓
• C. XO condition in humans as found in Turner’s syndrome, determines female sex
• D. Homozygous sex chromosomes (XX) produce male in Drosophila

Explanation: The correct answer is that the XO type of sex chromosomes determines male sex in grasshoppers. In these species, males have only one X chromosome (XO), making them heterogametic, while females have two X chromosomes (XX), making them homogametic. This system is part of the XX-XO type of sex determination. In contrast, birds have females with ZW sex chromosomes and males with ZZ. In humans, the typical female configuration is XX, while Turner’s syndrome (XO) results in a female phenotype with health issues. Drosophila males have XY sex chromosomes, not XX.

Q70. Lungs are made up of air­filled sacs, the alveoli. They do not collapse even after forceful expiration because of

• A. Inspiratory reserve volume
• B. Tidal volume
• C. Expiratory reserve volume
• D. Residual volume✓

Explanation: Even after a forceful expiration, a certain amount of air always remains in the lungs. This is called residual volume. It prevents the alveoli from collapsing completely, ensuring continuous exchange of gases (O₂ and CO₂) between breaths.

Q71. Kidney stones are formed due to :

• A. Infectious Diseases
• B. Metabolic Diseases✓
• C. Genetic Disease
• D. Congenital Diseases

Explanation: Kidney stones are formed due to metabolic diseases, which result in abnormalities in the body's normal chemical processes. This disruption can lead to the accumulation of substances that form stones in the kidneys. The other options, such as infectious diseases, genetic diseases, and congenital diseases, are not directly associated with the formation of kidney stones.

Q72. Ascending limb of loop of Henle does not allow_from its filtrate.

• A. Outflow of Sodium
• B. Outflow of Water✓
• C. Outflow of Salts
• D. Outflow of any Material

Explanation: Sodium is actively reabsorbed from filtrate under the influence of aldosterone hormone while passing through the ascending limb of loop of Henle, not water.

Q73. The possible reason(s) for cyanosis, one of congenital heart disease is:

• A. Formation of carboxy-hemoglobin✓
• B. The high concentration of oxyhemoglobin
• C. Low level of carbon monoxide (CO)
• D. Low level of hemoglobin

Explanation: The correct answer is the formation of carboxy-hemoglobin. This occurs when carbon monoxide binds to hemoglobin with a much higher affinity than oxygen, preventing adequate oxygen transport in the blood, leading to cyanosis. Option B is incorrect because a high concentration of oxyhemoglobin suggests well-oxygenated blood. Option C is incorrect because low levels of CO do not contribute to cyanosis. Option D is incorrect as low hemoglobin levels lead to anemia, not cyanosis.

Q74. XO in drosophila result in sterile:

• A. Female
• B. Male✓
• C. Both (A) & (B)
• D. No effect

Explanation: XO in drosophila results in a sterile male. As XO means the absence of the second chromosome. The male has only one X chromosome and one Y chromosome, while the female has two X chromosomes. So, when offspring of drosophila carry one X chromosome from a male and one X chromosome from a female it results in a normal female but when offspring of drosophila carry one X chromosome from a female and no chromosome from a male then it results in a sterile male.

Q75. How many sperms are produced from fifty secondary spermatocyte?

• A. 200
• B. 100✓
• C. 50
• D. 150

Explanation: The secondary spermatocyte continues into meiosis II and each spermatocyte forms two sperm. So, 2x50=100.

Q76. The first successful surgery of heart was performed by Dr. Ludwig by repairing a wound on which part:

• A. Right auricle
• B. Right ventricle✓
• C. Left auricle
• D. Left ventricle

Explanation: The first successful surgery of the heart was performed by Dr. Ludwig by repairing a wound on the Right ventricle.

Q77. Goblet cells are:

• A. Unicellular exocrine gland✓
• B. Unicellular endocrine glands
• C. Multicellular exocrine gland
• D. Multicellular endocrine glands

Explanation: The goblet cells are unicellular exocrine gland. Goblet cells are scattered in the epithelial linings of the intestinal and respiratory tracts. They secrete mucin and create a protective mucus layer.

Q78. A condition called Goose pimples, are caused by:

• A. Overcooled body✓
• B. Bacteria
• C. Environmental changes
• D. Pollution

Explanation: Option A is correct.The hairs in mammals act as insulating organs and reduce heat loss. Thus the heat is retained in the body to a certain extent. To increase the effect of insulation, the hairs are erected. This occurs involuntarily when the body is over-cooled. In humans, it produces Goose pimples.

Q79. In E.C.G QRS complex represent:

• A. Atrial systole
• B. Atrial diastole
• C. Ventricle systole✓
• D. Ventricle diastole

Explanation: The second part of ECG is the QRS complex which features a small drop in voltage (Q) a large voltage peak ( R ) and another small drop in voltage (S). The QRS complex corresponds to the depolarization of the ventricle during ventricle systole.

Q80. The common name of rubella is:

• A. Whooping cough
• B. German measles✓
• C. African sleeping sickness
• D. Tay Sach’s Disease

Explanation: It is also called German measles, but it is caused by a different virus than measles.

Q81. Human insulin is being commercially produced from a transgenic species of:

• A. Rhizobium
• B. Saccharomyces
• C. Escherichia✓
• D. Mycobacterium

Explanation: Insulin is now being commercially produced by genetic engineering. Insulin consists of two short polypeptide chains: chain A and chain B, that are linked together by disulphide bonds. Insulin in mammals is synthesized as a prohormone which contains an extra stretch called the C-­peptide. During maturation, this C­-peptide is removed. The production of insulin could only have been commercially possible if somehow the maturation process of C­-peptide could've been skipped.This problem was solved in 1988 by Eli Lilly, an American company that prepared functional insulin from two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of E.coli to produce insulin chains. In this way, chains A and B were produced separately, extracted and combined by creating disulfide bonds to get human insulin.

Q82. In PCR, primers are sequences of 20 bases that are complementary to the bases on either side of the:

• A. Target DNA✓
• B. DNA polymerase
• C. Primase
• D. RNA polymerase

Explanation: In PCR, primers bind to sequences flanking the target DNA to initiate replication.

Q83. The organism developed with two heads and one trunk is called:

• A. Identical twins
• B. Dizygotic twins
• C. Fraternal twins
• D. Siamese twins✓

Explanation: Siamese twins or also known as Conjoined twins. It is a very rare condition in which twins are joined side to side at the pelvis and part or all of the belly (abdomen) and chest but with separate heads. Such twins develop when an early embryo only partially separates to form two individuals.

Q84. XX-XY type of sex determination pattern is present in which of the following organisms?

• A. Humans
• B. Butterflies
• C. Grasshopper
• D. Drosophila
• E. Both A and D✓

Explanation: The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila), and some plants (Ginkgo).

Q85. Otitis media is an inflammation of which part of the

• A. Brain
• B. Middle ear✓
• C. Lungs
• D. Urinary tract

Explanation: Otitis media is an inflammation of the middle ear. The eustachian tubes equalise the pressure between the middle ear cavity and the outside mucus to drain out of the middle ear cavity. Inflammation of the middle ear causes the tubes to close, causing the fluid to become trapped. Bacteria travel from the back of the nose through the fluid in the eustachian tube directly into the middle ear cavity and multiply in the fluid.

Q86. How many nucleotides are in 12 mRNA codons?

• A. 12
• B. 24
• C. 36✓
• D. 48

Explanation: 12 mRna codons there are 36 nucleotides. As 3 nucleotide cob]combine to form one codon so 3 multiply by 12 gives 36.

Q87. Sarcolemma is the membrane around?

• A. Bone
• B. Joints
• C. Muscle fiber✓
• D. Heart

Explanation: The correct answer is muscle fiber because the sarcolemma is the plasma membrane that surrounds each muscle cell or fiber. It plays a crucial role in transmitting electrical impulses that trigger muscle contraction. The other options refer to different types of membranes: the periosteum for bones, the synovial membrane for joints, and the pericardium for the heart, each serving distinct functions unrelated to the sarcolemma.

Q88. Which one is not an opportunistic disease related to HIV infection:

• A. Destruction of body immune system✓
• B. Recurrent pneumonia
• C. Pulmonary tuberculosis
• D. Toxoplasmosis

Explanation: People with aids have badly damaged immune systems. They get an increasing number of severe illnesses called opportunistic infections which include tuberculosis toxoplasmosis and pneumonia.

Q89. What event is thought to have contributed to the evolution of eukaryotes ?

• A. Global warming
• B. Glaciations
• C. Volcanic activity
• D. Oxygenation of the atmosphere✓

Explanation: The production and release of oxygen, by cyanobacteria and algae, lead to evolution of eukaryotic cells as they contain a membrane-bound nucleus and are the building blocks of complex multicellular organisms

Q90. ABO Blood groups are an example of:

• A. Multiple alleles and incomplete dominance
• B. Co dominance and incomplete dominance
• C. Incomplete dominance only
• D. Multiple alleles and co dominance✓

Explanation: The human ABO blood group system exhibits codominance. It consists of three alleles A, B, and O. Both A and B show codominance

Q91. What will be the geometrical shape of a molecule that contains two lone pairs and two bond pairs of electron in valence shell of central atom?

• A. Tetrahedral
• B. Trigonal pyramidal
• C. Angular✓
• D. Linear

Explanation: If there are two bond pairs and two lone pairs of electrons the molecular geometry is angular or bent (e.g. H2O).

Q92. At higher altitude, the boiling point of water is less than 100°C. This is because of:

• A. Higher atmospheric pressure
• B. Weak hydrogen bonding
• C. No change in atmospheric pressure
• D. Lower atmospheric pressure✓

Explanation: Boiling point of water is lower at higher altitudes due to the decreased atmospheric pressure

Q93. How many elements are there in the third period of the periodic table?

• A. 18
• B. 8✓
• C. 32
• D. 10

Explanation: Second and third period are called short periods and contain eight elements.The third period contains eight elements: sodium, magnesium, aluminium, silicon, phosphorus, sulphur, chlorine, and argon

Q94. When ammonium cyanide (NH4CN) salt is dissolved in water the solution will be

• A. Neutral
• B. Acidic
• C. Basic✓
• D. Both acidic and basic

Explanation: Smaller the pKa , the stronger the acid. Very strong acids have pKa less than 1, moderately strong acids have pKa in between 1 to 5 and weak acids have pKa above 5.Ka is directly proportional to the H+ concentration and Kb is directly proportional to the OH- concentration.

Q95. In the complex, potassium hexacyanoferrate (III) K3 [Fe(CN)6] the coordination of the Fe is

• A. 9
• B. 3
• C. 6✓
• D. 5

Explanation: Coordination number, also known as ligancy, is the number of atoms, ions, or molecules that a central atom or ion carries in a complex or coordination compound or a crystal as its closest neighbours coordination number of Fe in K3[Fe(CN)6] is 6. Since the Fe atom is surrounded by six cyanide ligands which is mono-dentate, the coordination number is 6.

Q96. Tertiary alcohols are not oxidized into carbonyl compounds because

• A. They contain more alkyl group
• B. They have no alpha-hydrogen✓
• C. Suitable oxidizing agent is not available
• D. None of the above

Explanation: Tertiary alcohols are not oxidized by acidified sodium or potassium dichromate(VI) solution - there is no reaction whatsoever. During oxidation,oxidizing agent is removing the hydrogen from the -OH group, and a hydrogen from the carbon atom is attached to the -OH. Tertiary alcohols don't have a hydrogen atom attached to that carbon.

Q97. Fe+2 will form the most ionic bonds with:

• A. N-3✓
• B. S-2
• C. P-3
• D. F-1

Explanation: The stronger the charges on the cation and anion, the stronger the electrostatic attraction.Smaller ions can get closer → stronger attraction.Nitride(N3−) is smaller than phosphide (P3−)So Fe²⁺ + N³⁻ → stronger electrostatic attraction than Fe²⁺ + P³⁻Highest charge difference: 2+ and 3–Smallest anion radius: N³⁻

Q98. Which one is more reactive?

• A. HCHO✓
• B. CH3 CHO
• C. (CH3)2CO
• D. Have equal reactivity

Explanation: Aldehydes are usually more reactive toward nucleophilic substitutions than ketones because of both steric and electronic effects. In aldehydes, the relatively small hydrogen atom is attached to one side of the carbonyl group, while a larger R group is affixed to the other side. In ketones, however, R groups are attached to both sides of the carbonyl group. Thus, steric hindrance is less in aldehydes than in ketones. Electronically, aldehydes have only one R group to supply electrons toward the partially positive carbonyl carbon, while ketones have two electron‐supplying groups attached to the carbonyl carbon. The greater amount of electrons being supplied to the carbonyl carbon, the less the partial positive charge on this atom and the weaker it will become as a nucleus.

Q99. Which of the following elements has lower first ionization energy?

• A. N
• B. O
• C. C
• D. B✓

Explanation: The first ionization decreases from beryllium to boron, and from magnesium to aluminum, as electrons from the p-block start to come into play. In the case of boron, which has an electron configuration of 1s2 2s2 2p1, the 2s electrons shield the higher-energy 2p electron from the nucleus, making it slightly easier to remove. A similar effect occurs in aluminum, which has an electron configuration of 1s2 2s2 2p6 3s2 3p1. Even though oxygen is to the right of nitrogen in period 2, its first ionization energy is slightly lower than that of nitrogen. Nitrogen has an electron configuration of 1s2 2s2 2p3, which puts one electron in each p orbital, making it a half-filled set of orbitals.Half-filled sets of p orbitals are slightly more stable than those with 2 or 4 electrons, which makes it slightly harder to ionize a nitrogen atom. Oxygen has an electron configuration of 1s2 2s2 2p4, which puts another electron in one p orbital; since this is one electron away from being half-filled, it is slightly easier to remove this additional electron.

Q100. Which one of the following ions has more electrons than protons and more protons than neutrons?

• A. D
• B. d-
• C. H-✓
• D. He

Explanation: H is Hydrogen, it’s proton number is 1 so it has 1 proton, 1 electron and no neutrons. The ion of H gains an electron to attain the negative charge so now it has 2 electrons, 1 proton and 0 neutrons

Q101. A gas decolorized alkaline KMnO4 solution but does not give any PPT with ammoniacal AgNO3

• A. Methane
• B. Ethylene✓
• C. Ethane
• D. None of the above

Explanation: Option d) "None of the above" is incorrect because ethylene (option b) decolorizes KMnO4 but does not give a precipitate with ammoniacal AgNO3. Methane (option a) and ethane (option c) are both saturated hydrocarbons with only single bonds and are not reducing agents, so they would not decolorize KMnO4 or react with ammoniacal AgNO3 to form a precipitate. Therefore, the correct answer is option b) Ethylene.

Q102. Which one of the following elements has the largest second ionization energy:

• A. O
• B. F
• C. Na✓
• D. N

Explanation: Na has the largest second ionization energy as the second electron is removed from an inner shell, thus the nuclear charge acting on it is stronger and more energy is needed to remove an electron. After losing 1st electron, sodium gains electronic configuration of Neon (noble gas) which has completely filled orbital so it has the highest second ionization energy.

Q103. Which of the following species has the maximum number of unpaired electrons?

• A. O2✓
• B. O+2
• C. O-2
• D. O2-2

Explanation: O2 has 2 unpaired electrons, O+2 has no unpaired electrons, O-2 has paired electrons while O2-2 also has no unpaired electrons hence the correct option is A The number of unpaired electrons in an atom or ion can be determined by examining its electron configuration. Let's analyze the given species: 1. **O2**: Molecular oxygen (O2) has a total of 16 electrons (8 electrons per oxygen atom). Its electron configuration is 1s² 2s² 2p⁴. There are two unpaired electrons in the 2p orbital. 2. **O+2**: Oxygen cation (O+2) is formed by losing two electrons from O2. Its electron configuration becomes 1s² 2s² 2p³. There is one unpaired electron in the 2p orbital. 3. **O-2**: Oxygen anion (O-2) is formed by gaining two electrons by O2. Its electron configuration becomes 1s² 2s² 2p⁶. There are no unpaired electrons. 4. **O2-2**: This is a hypothetical species, as it would mean adding two more electrons to O-2, which is not energetically favorable. If you meant O-2, please refer to the explanation for O-2 above. Based on the analysis, **O2** has the maximum number of unpaired electrons with **two unpaired electrons**.

Q104. The oxidation states of Nitrogen in NH4NO3 are:

• A. -3 and +5✓
• B. +5 and -3
• C. -3 & -3
• D. Zero

Explanation: In NH₄NO₃, nitrogen is present in two different ions: NH₄⁺ and NO₃⁻. For NH₄⁺, the sum of oxidation states is +1. Since each hydrogen has an oxidation state of +1, the nitrogen must have an oxidation state of -3 to balance it (+1 = -3 + 4). For NO₃⁻, the sum of oxidation states is -1. Oxygen typically has an oxidation state of -2, so the nitrogen must be +5 to account for the charge (-1 = +5 - 6). Therefore, the correct oxidation states of nitrogen in NH₄NO₃ are -3 in NH₄⁺ and +5 in NO₃⁻.

Q105. Which equation relates to the first ionization energy of bromine?

• A. Br(g) → Br-(g) + 1e
• B. Br(g) → Br+(g) + 1e-✓
• C. 1/2 Br2(g) → Br-(g) + 1e-
• D. 1/2 Br2(g) → Br+(g) + 1e-

Explanation: Refer to folllowing explanation

Q106. Which one is more soluble in water?

• A. Secondary amines✓
• B. Tertiary amines
• C. Quatemary amines
• D. All are insoluble

Explanation: Lower amines can form hydrogen bonds with water thus making them more soluble.

Q107. How many d-block elements are present in the periodic table?

• A. 40✓
• B. 23
• C. 37
• D. 30

Explanation: There are 40 d-block elements in the periodic table. They are located in the center of the periodic table, between the s-block elements and the p-block elements. The d-block elements are divided into four series.

Q108. Which compound is the most reactive one?

• A. Ethyne
• B. Ethane
• C. Benzene
• D. Ethene✓

Explanation: Explanation:Correct answer is Ethene because the general order of reactivity is as follows: Alkene > Alkyne > AlkaneWhile Benzene is unique in its behavior though resembles alkenes in addition reactions but to high stability of the molecule it requires dramatic conditions for substitution reactions in order to generate electrophile.

Q109. The decrease in atomic radii is very prominent in the _.

• A. Second group
• B. Second period✓
• C. Higher groups
• D. Higher periods

Explanation: The decrease in atomic radii is very prominent in the second period. As you go across any period the atomic number or proton number increases while electron shielding remains constant which means the nuclear attraction is increasing. Due to increased nuclear attraction, the outermost electrons on the valence shell get attracted by the nucleus hence atomic radii keep decreasing.

Q110. What is the octane number of Iso-octane?

• A. 40
• B. 100✓
• C. Zero
• D. 2

Explanation: Octane number means the ability of any fuel to resist knocking when it is ignited in a mixture of air. N-heptane is a standard liquid that is used for octane number tests but unfortunately, it is a very poor knock resistance and is thus assigned a value of 0. While iso-octane which is also called 2,2,4-trimethylpentane is a very good knock resistance and is assigned a value of 100. So the answer is B.

Q111. More energy is needed to remove an electron from _.

• A. Half filled subshell
• B. Completely Filled Subshell
• C. Partially filled subshell
• D. Both A and B✓

Explanation: Half-filled subshells and completely filled subshells have a symmetrical distribution of electrons e.g. p3 or p6. p3 is a half-filled subshell but the electron distribution is symmetrical; p6 is a completely filled subshell and electrons here are also distributed symmetrically. The more symmetrical distribution, the more stable the element is so more energy is needed to remove an electron from it. So the answer is D.

Q112. A crystal is made up of _.

• A. Atoms
• B. Ions
• C. Molecules
• D. All of these✓

Explanation: Every crystalline solid is made up of atoms, ions, and molecules that are arranged in an ordered and symmetrical manner, and this is repeated over the entire crystal. The smallest repeating structure of any solid crystal is a unit cell. Therefore, every crystal is made up of atoms, ions, and molecules. Hence the answer is D.

Q113. What is the formula of chloroform?

• A. CH3Cl
• B. CH2Cl2
• C. CHCl3✓
• D. CH2Cl

Explanation: Chloroform or trichloromethane is an organic compound which has a molecular formula CHCl3. The answer is C.

Q114. In Down's Cell, the anode is made up of:

• A. Graphite✓
• B. Copper
• C. Iron
• D. Silver

Explanation: In a Down's cell, used for the electrolysis of molten sodium chloride to produce sodium metal, graphite is chosen as the anode material. This choice is due to graphite's high melting point, chemical stability, and excellent electrical conductivity, all of which are crucial for maintaining the integrity of the anode under extreme conditions.Copper, iron, and silver, on the other hand, either lack the necessary thermal resistance, could potentially react with the molten salt, or are prohibitively expensive for such an application, making graphite the most suitable material for the anode.

Q115. Which one of the following H-bond is strong?:

• A. O-H
• B. N-H
• C. F-H✓
• D. Cl-H

Explanation: This is the strongest hydrogen bond among the options, as fluorine is the most electronegative element, and its small size results in an extremely high degree of electron density and a correspondingly strong attraction to hydrogen.

Q116. Aldehydes and ketones can be obtained by the:

• A. Reduction of alcohol
• B. Oxidation of alcohol✓
• C. Dehydration of alcohol
• D. Hydrolysis of alcohol

Explanation: Option B (Oxidation of alcohol) is correct because the oxidation of primary alcohols leads to the formation of aldehydes, and the oxidation of secondary alcohols results in the production of ketones.

Q117. Which of the following element is present in all proteins but not in carbohydrates?

• A. Sulfur
• B. Carbon
• C. Nitrogen✓
• D. Oxygen

Explanation: Chemically, proteins are complex nitrogenous organic compounds, which are associated with the concept of life itself.By chemical composition, proteins are composed of carbon, hydrogen, oxygen, and nitrogen. Some proteins also contain smaller quantities of sulfur and phosphorus.The percentage of nitrogen is fairly constant and is about 16% of the molecular weight of protein. Hence, C is the correct option.

Q118. 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.

Q119. What is the color of iodoform precipitates?

• A. White
• B. Black
• C. Reddish
• D. Yellow✓

Explanation: This option suggests that the colour of iodoform precipitates is yellow. This statement is correct. Iodoform is a pale yellow solid, and when it precipitates during specific chemical reactions, it appears as yellowish flakes or crystals.

Q120. The molecules of solids possess _ kinetic energy?

• A. Translational
• B. Vibrational✓
• C. Both Options A & B are correct
• D. None of these options are correct

Explanation: Solids are rigid in nature as the particles of solids are held in fixed positions and cannot move freely. They can only vibrate about a mean position and thus transfer energy from one place to another. Thus, molecules of solids possess vibrational kinetic energy. Hence, B is the correct option.

Q121. Falling water of a waterfall is an example of:

• A. Reversible Reaction
• B. Spontaneous Reaction✓
• C. Endothermic Reaction
• D. All of these options are correct

Explanation: OPTION A: The reactions that do not go to completion and the products formed react to re-form the reactants are called reversible reactions.OPTION B: A spontaneous process occurs on its own, without any energy input from the outside. For example, a ball will roll down an incline; water will flow downhill; ice will melt into the water; radioisotopes will decay, and the iron will rust.Hence, B is the correct option.OPTION C: An endothermic reaction takes in energy from the surrounding and the system gains energy, the change in enthalpy, ΔH, is given a positive sign.EXAMPLES: Evaporating liquids, melting ice, dry ice, alkane cracking, thermal decomposition, etc.OPTION D: Incorrect

Q122. Shifting the position of equilibrium can be used to increase:

• A. Temperature
• B. Pressure
• C. Yield of reaction✓
• D. All of these options are correct

Explanation: Changing the position of equilibrium will cause the yield to increase towards the side that counters the change. For example, if the equilibrium position is changed towards the reactant side, more products will be formed to counter the change.

Q123. Which of the following oxidizing agents can oxidize "benzene"?

• A. KMnO4
• B. K2Cr2O7
• C. KHMnO4
• D. V2O5✓

Explanation: Vanadium pentoxide (V2O5) can be used as an oxidizing agent to oxidize benzene and its derivatives under specific conditions. V2O5 is a powerful oxidant commonly employed in organic synthesis.The oxidation of benzene by V2O5 in the presence of air produces maleic anhydride. The oxidation is carried out at 500o C.Hence, D is the correct option.

Q124. The increase in atomic radii in _ is due to an increase in the number of shells and the screening effect.

• A. Groups✓
• B. Periods
• C. Both A & B are correct
• D. None of these are correct

Explanation: OPTION A: As we move in a group from top to bottom, the number of shells and the effective nuclear charge increases but the effect of the addition of a new shell dominates over the effect of effective nuclear charge and hence the atomic size increases from top to bottom in a group. Hence, A is the correct option. OPTION B: As we move in a period from left to right, the number of shells remains the same as the electrons are added to the same shell. However, the effective nuclear charge increases and pulls the electron cloud closer to the nucleus. As a result, the atomic size decreases over a period. OPTION C: It is an incorrect option.OPTION D: It is an incorrect option.

Q125. Which of the following solvents favor SN2 reactions?

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

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

Q126. The number of isomers of C4H10 are:

• A. 2✓
• B. 4
• C. 6
• D. 5

Explanation: Butane has two isomers. The two chain isomers of butane (C4H10) are n-butane and isobutane.Hence, A is the correct option

Q127. The covalent crystals _ have giant molecules that are insoluble in all the solvents.

• A. Silicon carbide
• B. Diamond
• C. Both options A and B are correct✓
• D. None of these options are correct

Explanation: a) Silicon Carbide (SiC): Silicon carbide is a covalent crystal with a giant molecular structure. It consists of a three-dimensional network of covalently bonded atoms. Due to its strong covalent bonds, silicon carbide is insoluble in all solvents.b) Diamond: A diamond is also a covalent crystal with a giant molecular structure. It is composed of carbon atoms arranged in a tetrahedral lattice through strong covalent bonds. Like silicon carbide, diamond is insoluble in all solvents due to its robust covalent bonding.Therefore, both silicon carbide and diamond, being covalent crystals with giant molecular structures, are insoluble in all solvents, making option c) the correct answer.

Q128. In "Down Cells", the cathode is made up of:

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

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

Q129. Under which conditions, does a real gas approximate to an ideal gas?

• A. Pressure = highDensity = high
• B. Pressure = lowDensity = high
• C. Pressure = highDensity = low
• D. Pressure = lowDensity = low✓

Explanation: Real gases approximate ideal gas behavior at relatively low density, low pressure, and high temperature. At high temperatures, the gas molecules have enough kinetic energy to overcome intermolecular forces, but at low temperatures, the gas has less kinetic energy and thus the intermolecular forces are more prominent.

Q130. For the reaction,CO(g) + (1/2)O2(g) ⟶ CO2(g)

• A. Kp > Kc
• B. Kp < Kc✓
• C. Kp = Kc
• D. Kp ≥ Kc

Explanation: For the reaction. CO(g)+1/2O2(g) = CO2(g) Kp<Kc

Q131. The first ionization energy of an atom depends on:

• A. Charge on nucleus
• B. Screening effect
• C. Electronic configuration
• D. All of the above✓

Explanation: Ionization energy, also called ionization potential is the amount of energy required to remove an electron from an isolated atom or molecule. This energy is usually expressed in kJ/mol. It depends on the charge of the nucleus, shielding effect, and electronic configuration.The greater the charge on the nucleus, the more tightly the outer electrons are held, thus more heat energy is required to remove an electron from the atom.The greater the shielding/screening effect on the outer electrons, the less tightly they are held by the nucleus, thus less energy is required to remove an electron.The greater the distance from the nucleus (the electronic configuration), the lesser the force of nuclear attraction and the higher the ionization energy.

Q132. Chromium compounds in which oxidation state of chromium is 2+ behaves as a:

• A. Strong oxidizing agent
• B. Strong reducing agent✓
• C. Very weak oxidizing agent
• D. Very weak reducing agent

Explanation: The correct answer is that chromium compounds in which the oxidation state of chromium is 2+ behave as strong reducing agents. This is due to their ability to easily donate electrons, thereby reducing other substances and becoming oxidized themselves to higher oxidation states such as +3, +4, or +6.Option A, a strong oxidizing agent, is incorrect because chromium in the +2 state is more likely to be oxidized than to oxidize other substances. Option C, a very weak oxidizing agent, is incorrect for similar reasons, as it downplays the reducing capability of chromium(II). Option D, a very weak reducing agent, underestimates the reducing strength of chromium in this state, which can effectively donate electrons in chemical reactions.

Q133. Choose acids that are showing leveling effect:i) HClO4 ii)HI iii) HCI iv) HF

• A. i & iv
• B. i, iii, & iv
• C. iii & iv
• D. i, ii, & iii✓

Explanation: Leveling effect or solvent leveling refers to the effect of solvent on the properties of acids and bases. The strength of a strong acid is limited ("leveled") by the basicity of the solvent. Similarly the strength of a strong base is leveled by the acidity of the solvent Thus H2O is a differentiating solvent for HI HCl HClO4.HF is a weak acid so it doesn't show levelling effect.

Q134. Colloidal particles can be separated by using:

• A. Ordinary filter paper
• B. Coarse filter paper
• C. Fine Filter paper
• D. Extremely fine filter paper✓

Explanation: Colloidal particles are small solid particles that are suspended in a fluid phase. Their size range is typically between 10nm. Colloidal particles can be separated by a centrifugation method using fine filter.

Q135. Which group when attached to benzene will increase its reactivity:

• A. –NH4+✓
• B. –NH3
• C. –C≡N
• D. –COR

Explanation: Activating groups are Atoms or groups that make the benzene molecule more reactive by increasing the ring's electron density.The resonance structures suggest that the amino group increases the electron density only at ortho- and para-positions of the ring, making them more preferred to the electrophilic attack as they make the benzene more negative thus NH4+ can be used as activating group.

Q136. A particle performs uniform circular motion with angular momentum 'L'. If the frequency of the particle's motion is halved and its KE is doubled then the angular momentum becomes:

• A. L/4
• B. 4L✓
• C. 2L
• D. L/2

Explanation: The angular momentum L of a particle in uniform circular motion is given by L = Iω, where I is the moment of inertia and ω is the angular velocity. When the frequency is halved, the angular velocity is also halved, reducing L to L/2. However, doubling the kinetic energy implies a change in velocity that affects both I and ω. The kinetic energy KE is proportional to the square of the velocity, so doubling KE implies a root 2 increase in velocity, doubling ω. Ultimately, considering both effects, the angular momentum becomes 4L due to the combined changes in frequency and kinetic energy.

Q137. 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

Q138. A block hangs freely from the end of a spring. A boy then slowly pushes the block upwards so that the spring becomes strain free. The gain in gravitational potential energy of the block during this process is equal to:

• A. Work done by the boy against the gravitational force acting on the block
• B. Loss of energy stored in the spring minus the work done by the tension in the spring
• C. Work done on the block by the boy plus the loss of energy stored in the spring✓
• D. Work done on the block by the boy minus the work done by the tension in the spring

Explanation: Let xo be the initial extension of the spring. Then the initial energy stored in the spring is: ½kxo2The gain in gravitational potential energy: mgh = mgxoThe work done increases the gravitational potential energy and decreases the spring’s potential energy. The total energy gained = gain in the gravitational potential energy - loss in spring’s potential energy. Therefore, work done by the boy (wb) = gain in the gravitational potential energy - loss in spring’s potential From here you can see that the gain in the gravitational potential energy of the block = work done by the boy + loss in the spring’s potential energy. Therefore, option C is the correct one.

Q139. A container is filled with oxygen and helium at the same temperature. The molar mass of oxygen is 32 g/mol and that of helium is 4 g/mol. What is the ratio:average speed of oxygen molecules / average speed of helium molecules

• A. 1/√8✓
• B. √8
• C. 1/8
• D. 8

Explanation: Average speed of a molecule is directly proportional to the square root of the temperature at which the gas is kept and indirectly proportional to the molar mass of the gas.FORMULA: √(8RT)/(πM), where R is the universal gas constant (8.3144 J/K mol), T stands for the temperature in kelvins, and M is the molar mass of the molecule.Since the temperature for both gases is same and 8R/π is a constant, therefore the average speed depends inversely on the molar mass of gas.- Let average speed of oxygen be v1 and average speed of helium be v2.Molar mass of oxygen (m1) = 32 g/molMolar mass of helium (m2) = 4 g/molUsing the formula:v1 / v2 = √m2/m1v1 / v2 = √4/32v1 / v2 = √1/8Therefore the ratio of average speed of oxygen molecules and helium molecules is option A ( 1 : ✓8 ).

Q140. If f1 and f2 are frequencies of two tuning forks, such that f1 < f2, then the number of beats produced in one second is:

• A. f2 - f1✓
• B. f2 x f1
• C. f1 - f2
• D. f2 + f1

Explanation: If the two waves are in phase t=0, they will be in phase when the first wave has gone through exactly one more cycle than the second. This will happen at a time t=T, the period of the beat.Let n be the number of cycles of the first wave in time T, then the number of cycles of the second wave at the same time is (n-1). Hence, T = Nt1 = (n-1)T1.

Q141. A cyclist is travelling at 15 ms-1, she applies brakes so that she doesn't collide with the wall in front of her at a distance of 18 m. Calculate the magnitude of deceleration.

• A. 6.3 ms-2✓
• B. 5.3 ms-1
• C. 13 ms-1
• D. 12.5 ms-1

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

Q142. At every point of the trajectory of projectile, which of the following quantities is always zero?

• A. Horizontal velocity
• B. Total velocity
• C. Vertical acceleration
• D. Horizontal acceleration✓

Explanation: Projectile motion can be analyzed by breaking it down into horizontal and vertical components. In the absence of air resistance, the horizontal velocity of a projectile remains constant throughout its trajectory, and there is no horizontal acceleration.The vertical motion of a projectile is affected by gravity, so there is a constant vertical acceleration throughout the motion. However, at the highest point of the trajectory, the vertical velocity of the projectile becomes zero before changing direction and starting to move downward. Therefore, neither the vertical velocity nor the total velocity is always zero throughout the trajectory.Thus, the only quantity that is always zero throughout the projectile's trajectory is the horizontal acceleration.

Q143. Infrasonic waves have a frequency of:

• A. Greater than 20000 Hz
• B. Less than 20 Hz✓
• C. 20 Hz
• D. Greater than 20 Hz

Explanation: Infrasonic waves are waves with frequencies below the human audible range i.e. 20-20000 Hz

Q144. A body of mass 5 kg, projected at an angle of 45° from the ground covers a horizontal range of 45 m. The acceleration due to gravity is g = 10 m/s^2. What is the velocity with which it was projected?

• A. 22.5 m/s
• B. 20 m/s
• C. 19.8 m/s
• D. 21.21 m/s✓

Explanation: Explanation is given below.

Q145. The voltage in the primary and the secondary coils of a step-up transformer are 200V and 4KV respectively. If the current in the primary is 1 ampere then the current in the secondary coil will be

• A. 50mA✓
• B. 5A
• C. 500mA
• D. 1.5mA

Explanation: Explanation is giving below:

Q146. The wavelength associated with an electron is of the order of:

• A. Visible light
• B. X rays✓
• C. Radio waves
• D. Infrared

Explanation: The correct answer is X-rays. Electrons, when moving at high speeds, such as in a hydrogen atom or in a particle accelerator, have wavelengths that fall within the X-ray region of the electromagnetic spectrum. This range is approximately 0.01 nm to 10 nm, which is much shorter than visible light, infrared, or radio waves. Visible light ranges from 400 nm to 700 nm, infrared from ~700 nm to 1 mm, and radio waves from 1 mm to 100 km, all of which are much longer than electron wavelengths.

Q147. If a half wave rectifier is used to convert 50Hz AC into DC, then the number of pulses present in rectified voltage is:

• A. 25
• B. 50✓
• C. 100
• D. 75

Explanation: Rectifiers produce unidirectional and pulsating voltage from A.C. source, the number of pulses per second in the rectified voltage remains same as that of input voltage, i.e., here it is 50 Hz.

Q148. In which rectifier is the ripple factor less?

• A. Full wave✓
• B. Half wave
• C. Both A and B
• D. None of them

Explanation: Lower the value of the ripple factor higher will be the efficiency of the rectifier. As we know that half-wave rectifier is less efficient as compared to a full-wave rectifier, hence, its ripple factor is greater than that of a full-wave rectifier and its value is 1.21.

Q149. The output voltage of a rectifier is:

• A. Smooth
• B. Pulsating✓
• C. Perfectly direct
• D. Alternating

Explanation: A rectifier is used to convert alternating current to pulsating direct current not smooth direct current. Perfectly direct current will have fixed magnitude and fixed direction of current. This is not true for the output of a rectifier. Hence, option B is correct.

Q150. A TV tower has a height of 100m. The average population density around the tower is 1000 per km2 . The radius of the earth is 6.4x106 m. × The population covered by the tower is

• A. 2x106
• B. 3x106
• C. 4x106✓
• D. 6x106

Explanation: d = √(2Rh)where:• d = maximum distance covered by the tower• R = radius of the Earth = 6.4 * 10 ^ 6 m• h = height of the tower = 100mStep 1: Calculate the Coverage Radiusd = √(2(6.4 ×10 ^ 6) × 100) d = √{1.2×10^9}]A = πd ^ 2A = 3.14 × (35.8) ^ 2A = 3.14 × 1280A = 4020 km ^ 2Given that the population density is 1000 people per km², the total population covered is:Population = Area × Density4020 × 1000= 4.02 × 10^6

Q151. The diode used in the circuit shown in the figure has a constant voltage drop of 0.5 V at all currents and a maximum power rating of 100 milliwatts. What should be the value of the resistor R, connected in series with the diode, for obtaining maximum current?

• A. 1.5 Ω
• B. 5Ω✓
• C. 6.67 Ω
• D. 200 Ω

Explanation: Maximum current in the circuitI = P/VHere, P = 100 × 10⁻³ watts and V = 0.5 volts, soI = 100 × 10⁻³ / 0.5 = 0.2 amp.The resistance is given byR = voltage drop across resistance / current = 1 / 0.2 = 5 ohm.

Q152. The valence band and conduction band of a solid overlap at low temperature, the solid may be:

• A. A metal✓
• B. A semiconductor
• C. An insulator
• D. None of these

Explanation: In the band theory of solids, conductors like metals are characterized by an overlap between the valence band and the conduction band. This overlap enables electrons to move freely, allowing metals to conduct electricity at low temperatures without requiring additional energy to excite electrons. In contrast, semiconductors have a small band gap with no overlap, and insulators have a large band gap, preventing electron movement between the bands. Therefore, the correct answer is that the solid is a metal.

Q153. Which two or more of the following actions would increase the energy stored in a parallel plate capacitor when a constant potential difference is applied across the plates?

• A. Decreasing the area of the plates. Decreasing the separation between the plates
• B. Decreasing the area of the plates. Increasing the separation between the plates Inserting a dielectric between the plates
• C. Increasing the area of the plates. Decreasing the separation between the plates. Inserting a dielectric between the plates✓
• D. Increasing the area of the plates. Increasing the separation between the plates

Explanation: The energy is directly proportional to the area, so as the area increases, the energy will increaseThe energy is inversely proportional to the distance, so as the distance decreases, the energy will increaseThe energy increases if the value of k increases (that is, if a dielectric is put between the plates)

Q154. The transverse nature of light is shown by

• A. Interference of light
• B. Refraction of light
• C. Polarization of light✓
• D. Dispersion of light

Explanation: A light wave is an electromagnetic wave which travels through the vacuum of outer space and transparent materials like glass. Electromagnetic waves are transverse waves in the sense that the plane of the wave vibrations is different from the plane of wave propagation. The electromagnetic waves in the true sense have the direction of propagation perpendicular to the direction of its electric and magnetic fields. In the case of polarized waves, the electric and magnetic fields are also at right angles to each other. Polarized light waves are electromagnetic waves in which the vibrations occur in a single plane. Light can be polarized by transmission, reflection, refraction or scattering. Using a polaroid filter, different planes of vibration of polaroid filters can be blocked due to the special material used there. Due to the polarization of light, it is evident that light is a transverse wave.

Q155. A car battery has EMF of 12 volts and internal resistance 5 × 10-2 ohm. If it draws 60 ampere current, then terminal voltage of the battery will be:

• A. 5 volts
• B. 3 volts
• C. 15 volts
• D. 9 volts✓

Explanation: E= V+IrV = E–Ir = 12–(60)(5×10-2) = 9 volts

Q156. The cyclotron frequency of an electron projected with velocity perpendicular to a magnetic field B is given by:

• A. f= mB/πC
• B. f= 2πeB/m
• C. f= eB/2πm✓
• D. f= 2πc/mB

Explanation: For a cyclotron Centripetal force is provided by magnetic force.By derivation, A, B & C are wrong.

Q157. A metal cube with sides of length “𝑎” has electrical resistance 𝑅 between opposite faces. What is the resistance between the opposite faces of a cube of the same metal with sides of length 3𝑎?

• A. 9𝑅
• B. 3𝑅
• C. R/3✓
• D. 𝑅/9

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

Q158. Tesla is a unit of _ per unit area.

• A. Magnetic field lines✓
• B. Electric field lines
• C. Optical field lines
• D. Gravitational field lines

Explanation: The tesla (T) is the unit of magnetic flux density also called magnetic B-field strength. One tesla is equal to one weber per square meter. Using the equation , where E or magnetic flux density is equal to magnetic flux/ Area, (magnetic flux means magnetic field lines). Magnetic flux density (E) has units tesla and magnetic field lines have unit weber.

Q159. A cell of internal resistance 2.0Ω and electromotive force (e.m.f) 1.5V is connected to a resistor of resistance 3.0Ω. What is the potential difference across the 3.0Ω resistor?

• A. 5V
• B. 1.2V
• C. 0.9V✓
• D. 0.6V

Explanation: Rtotal = Internal resistance of the cell + Resistance of the external resistorRtotal = 2.0Ω + 3.0ΩRtotal = 5.0ΩCalculate the current (I) flowing through the circuit using Ohm's law:I = (e.m.f) / (Rtotal )I = 1.5V / 5.0ΩI = 0.3A (amperes)Finally, calculate the potential difference (V) across the 3.0Ω resistor using Ohm's law:V = I * R (where I is the current and R is the resistance of the resistor)V = 0.3A * 3.0ΩV = 0.9V

Q160. Work function for a certain surface is 3.3 ev. Minimum frequency, light must have in order to eject electron from surface will be:

• A. 8 x 1014 Hz✓
• B. 3.2 x 1015 Hz
• C. 4.8 x 1015 Hz
• D. 6.4 x 1015 Hz

Explanation: The correct option is A.To calculate the minimum frequency of light required to eject an electron from a surface, we need to use the formula:f = (W/E)where f is the minimum frequency, W is the work function, and E is the energy of a photon of light.Since the work function is given as 3.3 eV, we first need to convert it to joules using the conversion factor 1 eV = 1.6 x 10^-19 J:W = 3.3 eV x 1.6 x 10^-19 J/eV = 5.28 x 10^-19 JThe minimum energy of a photon required to eject an electron is equal to the work function, so we have:E = W = 5.28 x 10^-19 JNow we can plug in these values into the formula and solve for f:f = (W/E) = (5.28 x 10^-19 J) / (6.63 x 10^-34 J s) = 7.97 x 10^14 Hzwhich is approximately equal to 8 x 10^14 Hz. As it is numerical, it can have only one answer.

Q161. The decay constant λ of a radioactive sample:

• A. Decrease as the age of atoms increase
• B. Increase as the age of atoms increase
• C. Is independent of the age✓
• D. Depends on the nature of activity

Explanation: The decay constant is a property of the radioactive material itself, and it does not change over time. This means that the rate of decay of a radioactive sample will be the same regardless of how old the sample is.

Q162. In transmission from grid station, power losses are minimized by:

• A. Decreasing current
• B. Decreasing resistance
• C. Increasing resistance
• D. Increasing voltage✓

Explanation: Efficient power transmission is achieved by using transformers to increase the voltage, which reduces the current according to the formula P = IV, where P is power, I is current, and V is voltage. By decreasing the current, power losses due to resistance (P = I^2R) are minimized. Transformers allow the voltage to be stepped up for long-distance transmission, and then stepped down for safe distribution at the destination.Decreasing or increasing resistance directly is not practical or efficient due to cost and material limitations. Directly decreasing current is not feasible without a corresponding increase in voltage. Therefore, increasing the voltage is the correct and efficient method to minimize power losses.

Q163. The domestic electricity supply has a frequency of:

• A. 150 Hz
• B. 100 Hz
• C. 50 Hz✓
• D. 25 Hz

Explanation: The standard frequency for domestic electricity supply varies around the world, but it is commonly 50 Hertz (Hz). The specific frequency depends on the region and the standards established by the local electrical grid.It's important to note that the frequency of the electricity supply is a key parameter in electrical systems and devices, and appliances are designed to operate at the frequency of the local power grid.

Q164. PIV stands for :

• A. Positive inverse voltage
• B. Pawn Bh Integrated voltage
• C. Peak inverse voltage✓
• D. Peak integrated voltage

Explanation: Peak Inverse Voltage (PIV) or Peak Reverse Voltage (PRV) refer to the maximum voltage a diode or other device can withstand in the reverse-biased direction before breakdown. Also may be called Reverse Breakdown Voltage.

Q165. In a full-wave bridge rectification, the number of diodes used are:

• A. 1
• B. 2
• C. 3
• D. 4✓

Explanation: A full-wave bridge rectifier consists of 4 diodes arranged in a bridge configuration. This arrangement allows the rectifier to convert both halves of an AC waveform into a pulsating DC output. When the positive half-cycle of the AC input is applied, diodes D1 and D2 conduct, allowing current to flow through the load. During the negative half-cycle, diodes D3 and D4 conduct, again directing current through the load in the same direction. This ensures that the load always receives a unidirectional current. Options A, B, and C are incorrect because they do not provide the necessary number of diodes to achieve full-wave rectification in a bridge configuration.

Q166. Which photon carries the most energy?

• A. Blue
• B. Violet✓
• C. Red
• D. Green

Explanation: VIBGYORFrom left to right:Wavelength increases.Frequency decreases.Energy(hf) decreases ->-> so energy decreases from violet to red.Maximum energy is that of violet.

Q167. The main difference between X rays and Y rays is:

• A. Frequency
• B. Wave length
• C. Energy
• D. Origin✓

Explanation: The main difference is of origin : x-rays are emitted by electrons outside the nucleus, and gamma rays are emitted by the excited nucleus itself, so the main difference is that of the origin.

Q168. There are initially 400 atoms in a radioactive sample. What would be the number of atoms after 3 half - life?

• A. 400
• B. 200
• C. 50✓
• D. 25

Explanation: After each half-life the number of radioactive sample becomes half. First Half Life: 400->200 Second Half life: 200->100 Third Half life: 100->50.

Q169. While using radiation therapy, cancerous thyroid is treated with _ radioisotope:

• A. Carbon
• B. 235 Uranium
• C. Thorium
• D. Iodine - 131✓

Explanation: Radioactive Iodine(also called RAL) can be used to treat thyroid cancer.

Q170. Ohm time’s farad is equivalent to:

• A. Time✓
• B. Charge
• C. Distance
• D. Capacitor

Explanation: The formula for charging and discharging capacitor is RC=T R: resistance C: capacitance T: time for charging/ discharging

Q171. Iodine-131 is used to trace which cancer:

• A. Lungs
• B. Thyroid gland✓
• C. Breast
• D. Liver

Explanation: Your thyroid gland absorbs nearly all of the iodine in your body. Because of this, radioactive iodine (RAI, also called I-131) can be used to treat thyroid cancer.

Q172. Directions: In the following question, a number sequence is given with one term missing. Choose the correct term that will continue the same pattern and replace the question mark in the given sequence.2,6,18,54,162,?

• A. 486✓
• B. 324
• C. 243
• D. 450

Explanation: The given sequence is 2, 6, 18, 54, 162, ?. To find the pattern, observe that each term is obtained by multiplying the previous term by 3:6 is 2 × 318 is 6 × 354 is 18 × 3162 is 54 × 3Continuing this pattern, the next term is 162 × 3 = 486. Therefore, the missing term is 486. The other options do not follow this multiplication rule, thus they are incorrect.

Q173. Directions: Read the following information and give answer.A rat runs 20' towards East and turns to right, runs 10' and turns to right runs 9' and again turns to left, runs 5' and then turns to left, runs 12' and finally turns to left and runs 6' Now, which direction is the rat facing?

• A. East
• B. West
• C. North✓
• D. South

Explanation: To determine the final direction the rat is facing, follow these steps:The rat starts by running 20' East.It turns right (now facing South) and runs 10'.It turns right again (now facing West) and runs 9'.It turns left (now facing South) and runs 5'.It turns left again (now facing East) and runs 12'.Finally, it turns left (now facing North) and runs 6'.After these movements, the rat is facing North. The rat makes a total of four left turns and two right turns. The final orientation is determined by the cumulative effect of these directional changes.Other options such as East, West, or South are incorrect because they do not match the final orientation after considering all movements and turns.

Q174. In this section of logical deduction, the question consists of a brief passage (usually a report containing certain data regarding some social or economic problem), followed by certain inferences based on it. The student is required to analyze the contents (or data) of the passage and grasp the desirable facts from it. Then, student has to consider each of the given inferences in the context of the given passage. decide upon its degree of truth or falsity and then choose the hest alternative provided accordingly.The water resources of our country are very much underutilized. The main reason of this underutilization is the lack of capital and technology. A large portion of our water resources is wasted due to floods and unwise use of water for irrigation as well as domestic purposes. We can make full use of our water resources by building dams on rivers and by adopting policy of awareness among people not to waste water.The country does not have enough funds to utilize such water resources.

• A. Definitely true✓
• B. Probably true
• C. Data inadequate
• D. Probably false
• E. Definitely false

Explanation: The correct answer is 'Definitely true'. The passage clearly states that the primary cause for underutilization of water resources is the lack of capital and technology. This directly supports the statement that the country does not have enough funds to develop its water resources. Other options are incorrect because they either misinterpret the definitiveness of the passage's information or contradict the explicit statements made within it.

Q175. Statements:Some blankets are beds. Some pillows are blankets. All beds are pillows.Conclusions:I. Some blankets are pillows.II. Some pillows are beds.III. Some beds are blankets.Which of the following is/are most appropriate in the above scenario?

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

Explanation: All conclusions I, II, and III are correct based on the given statements. Conclusion I: Some blankets are pillows, is substantiated by the fact that some blankets are beds and all beds are pillows. Conclusion II: Some pillows are beds, follows from the statement that all beds are pillows, implying that some pillows must be beds. Conclusion III: Some beds are blankets, is directly stated. Therefore, the correct option is D: I, II, and III. The other options are incorrect as they do not account for all the valid conclusions drawn from the given statements.

Q176. Statements:I. There is an unprecedented increase in the number of young unemployed in comparison to the previous year.II. A large number of candidates submitted applications against an advertisement for the post of manager issued by a bank.

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

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

Q177. Dependent causes/ Independent causes:Statement I: There has been a high increase in the incidents of atrocities against women in the city during the past few months. Statement II: The police authority has been unable to nab the culprits who are committing crimes against women.

• 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 Statement I and II are independent causes
• D. Both Statement I and II are effects of independent causes

Explanation: In this scenario, Statement II, which mentions the police's inability to catch the culprits, serves as a cause that contributes to the rising incidents of atrocities against women described in Statement I. Therefore, it is accurate to say that Statement II is the cause and Statement I is the effect. The other options are incorrect as they misunderstand the relationship between the two statements. Option A incorrectly identifies the cause and effect, Option C suggests both statements are independent causes without interaction, and Option D treats both as outcomes of unrelated factors, which is not supported by the context of the statements.

Q178. Passage: There is a family of six persons G, J, B, E, T and Z. Their professions are teacher, writer, actor, singer, dancer and lawyer but not respectively in the same order. G is a teacher. Z is a dancer. B is neither writer nor actor. E is neither singer nor lawyer. T is an actor. J is a lawyer. Who among them has a profession of lawyer?

• A. J✓
• B. B
• C. E
• D. T

Explanation: The passage explicitly states, "J is a lawyer." Therefore, J is the person with the profession of a lawyer.

Q179. Directions: Read the following information and give answer.There are six persons A, B, C, D, E and F. C is the sister of F. B is the brother of E's husband. D is the father of A and grandfather of F. There are two fathers, three brothers and amother in the group.Which of the following is a group of brothers?

• A. ABF✓
• B. ABD
• C. BFC
• D. BDF
• E. None of them.

Explanation: The correct group of brothers is A, B, and F. Here’s the breakdown: D is the father of A and the grandfather of F, indicating a direct lineage from D to A to F. C is mentioned as the sister of F, which confirms F's siblings. B is the brother of E's husband, who is A. Therefore, A and B are brothers, and since F is A's son, he is also a brother in this context. Other options are incorrect as they either include a female or a father in the group of brothers, which contradicts the given relationships.

Q180. If - means *, * means +, + means / and / means -, then 40 * 12 + 3 - 6 / 60 = ?

• A. 1
• B. 2
• C. 3
• D. 4✓
• E. None of the above

Explanation: First, substitute the symbols in the expression as follows:- means *, * means +, + means /, and / means -.This transforms the given expression 40 * 12 + 3 - 6 / 60 into 40 + 12 / 3 * 6 - 60.Now, follow the order of operations (BODMAS/BIDMAS):40 + 12 / 3 * 6 - 6040 + (12 / 3) * 6 - 6040 + 4 * 6 - 6040 + 24 - 6064 - 60= 4Therefore, the correct answer is Option D: 4. Other options are incorrect as they do not match the calculated result.