Federal Mdcat 2025 — Solved Past Paper with Answers

Q1. What does "I've told you a million times" means?

• A. To provide an exact count
• B. To emphasize frustration or impatience✓
• C. To confuse the listener
• D. To make the character sound foolish

Explanation: The correct answer is option B: To emphasize frustration or impatience. This expression is often used in everyday language to convey that the speaker has repeated themselves numerous times, leading to feelings of annoyance or impatience about having to say the same thing again. Option A is incorrect because the phrase does not literally mean an exact count; it's an exaggeration. Option C is also incorrect as the phrase does not aim to confuse the listener, but rather to express a common frustration. Lastly, option D is incorrect because the intention of the phrase is not to depict foolishness, but rather to communicate the speaker's annoyance.

Q2. Traveling in hot, dusty terrain gives me no pleasure. The underlined part of the sentence is:

• A. Adverb phrase
• B. Prepositional phrase
• C. Noun phrase✓
• D. Infinitive phrase

Q3. Identify the sentence with no spelling errors.

• A. Rabia completes homework assignments well in time✓
• B. Rabia complete homwork assignments well in time.
• C. Rabia completes homework asignments well in time.
• D. Rabia completes homework assigments well in time.

Explanation: The correct answer is the first option: Rabia completes homework assignments well in time as it contains no spelling errors and is grammatically correct. The other options each contain spelling errors: 'homwork' in Option B, 'asignments' in Option C, and 'assigments' in Option D, which makes them incorrect. To identify the correct sentence, it is essential to look for any misspellings.

Q4. The team won the match, ............ they broke the school record.

• A. Similarly
• B. Nevertheless
• C. Furthermore✓
• D. Instead

Explanation: The correct answer is 'Furthermore' as it effectively links the two achievements of the team, emphasizing that winning the match is complemented by the breaking of the school record. The other options do not appropriately connect the ideas. 'Similarly' suggests a comparison rather than an addition of information, 'Nevertheless' implies a contradiction, and 'Instead' fails to convey a relationship between the two events.

Q5. People approach the situation differently depending on who they are. The word 'approach' in this sentence means..........

• A. relate
• B. coordinate✓
• C. comprehend
• D. verify

Explanation: The correct answer is 'coordinate' because it captures the essence of how individuals manage their responses to various situations. In the context of the sentence, 'approach' implies a method or strategy that people use when dealing with circumstances. The other options, while related to aspects of engagement, do not fully reflect the active and strategic nature of 'approaching' a situation.

Q6. Pick out the sentence which illustrates the use of infinitive.

• A. He refused to obey the orders.✓
• B. He refused obeying the orders.
• C. He refused obey the orders.
• D. He refused obeyed the orders.

Explanation: The correct answer is Option A: 'He refused to obey the orders.' This sentence uses the infinitive form 'to obey' which indicates the action that is being refused. In contrast, Option B uses 'obeying', which is a gerund and does not represent the infinitive form. Option C omits 'to' before 'obey', making it incorrect, and Option D incorrectly uses 'obeyed', which is a past tense form, thus failing to illustrate the infinitive structure.

Q7. Identify the example of complex sentence.

• A. I both thanked him and rewarded him.
• B. Life is what we make it.
• C. He owed his success to his father.
• D. Jumping up, he ran away.✓

Explanation: The correct answer is Option D: Jumping up, he ran away. This sentence is classified as complex because it contains a participial phrase that provides context to the main action. The phrase 'Jumping up' is not a complete thought by itself, making it dependent on the main clause 'he ran away'.In contrast, Option A is a compound sentence with two independent clauses, Option B is a simple sentence, and Option C also presents a single independent clause. None of these options include the necessary dependent clause structure that defines a complex sentence.

Q8. The book was written by Rashid Khan. Identify the correct usage of voice.

• A. Rashid Khan writes the book.
• B. Rashid Khan wrote the book.✓
• C. Rashid Khan written the book.
• D. Rashid Khan has write the book.

Explanation: The correct answer is 'Rashid Khan wrote the book.' This sentence correctly uses the simple past tense to indicate that the action of writing has already taken place. The other options are incorrect for the following reasons: 'Rashid Khan writes the book.' uses the present tense, which does not fit the context. 'Rashid Khan written the book.' is incorrect because it lacks an auxiliary verb needed to form the perfect tense. Lastly, 'Rashid Khan has write the book.' is grammatically incorrect as it should use 'has written' instead of 'has write'.

Q9. What is the effect of using different shades of meaning in satire?

• A. To create a serious tone
• B. To highlight the absurdity or irony of a situation✓
• C. To confuse the reader
• D. To add complexity to the language

Explanation: The correct answer is B: 'To highlight the absurdity or irony of a situation.' In satire, different shades of meaning are employed to reveal contradictions and exaggerate situations, which effectively draws attention to the absurdities being critiqued. This use of nuanced language is essential in conveying the satirical message. Options A and C miss the mark by focusing on tone or confusion, which are not the primary goals of satire. Option D, while acknowledging complexity, fails to recognize that the main purpose is to underscore irony and absurdity rather than merely complicate the language.

Q10. A mutation prevents proper disulphide bond formation in a fibrous protein, causing brittle nails and slow hair growth. Which of the following proteinaceous substances would be affected?

• A. Elastin
• B. Actin
• C. Keratin✓
• D. Collagen

Explanation: The correct answer is Keratin because it is a fibrous protein that plays a critical role in the structure of hair and nails. Disulphide bonds in keratin provide the necessary strength and integrity for these structures. The mutation mentioned in the question disrupts the formation of these bonds, leading to the observed symptoms of brittle nails and slow hair growth. In contrast, Elastin and Actin are proteins that do not primarily rely on disulphide bonds for their function and are involved in different physiological roles, such as elasticity and cellular movement, respectively. Collagen is also a structural protein but is associated with connective tissues rather than directly influencing hair and nail structure. Therefore, it is not the protein most affected in this scenario.

Q11. In muscle fibers, T-tubules are extension of the sarcolemma that penetrates into the cell's interior. What is their main function during muscle contraction?

• A. Unblock actin's binding sites
• B. Conduct nerve impulses deep into the muscle cell✓
• C. Synthesize glycogen in the sarcoplasm
• D. Store calcium ions in the sarcoplasmic reticulum

Explanation: The correct answer is Option B: Conduct nerve impulses deep into the muscle cell. T-tubules (transverse tubules) are specialized extensions of the sarcolemma that penetrate into the muscle fiber, allowing action potentials to travel deep into the cell. This is crucial for initiating muscle contraction as it leads to the release of calcium ions from the sarcoplasmic reticulum, which is essential for the interaction between actin and myosin.Option A is incorrect because T-tubules do not unblock actin's binding sites; they facilitate communication within the muscle cell. Option C is incorrect as T-tubules are not responsible for glycogen synthesis; this function is performed by other cellular components. Option D is also incorrect because while T-tubules are associated with the sarcoplasmic reticulum, they do not store calcium ions; instead, the sarcoplasmic reticulum is responsible for calcium storage and release during muscle contraction.

Q12. Which of the following hormones in the body of animal is lipid-based nature?

• A. Insulin
• B. FSH
• C. Oxytocin
• D. Aldosterone✓

Explanation: The correct answer is Aldosterone, as it is a steroid hormone, which means it is derived from lipids and is lipid-soluble. Steroid hormones, including aldosterone, are synthesized from cholesterol and can easily pass through cell membranes to exert their effects. In contrast, the other options listed are peptide hormones, which are made from amino acids and are water-soluble. Insulin is crucial for glucose metabolism, FSH is important for reproductive health, and oxytocin is involved in childbirth and emotional bonding; none of these are lipid-based.

Q13. Which of the following base pairing maintains the constant diameter of the DNA double helix as per Watson and Crick's model?

• A. Purine - Purine
• B. Pyrimidine - Pyrimidine
• C. Purine - Pyrimidine✓
• D. Sugar-Phosphate

Explanation: In Watson and Crick's model of DNA, the double helix structure is maintained through specific base pairing between purines and pyrimidines. A purine (adenine or guanine) pairs with a pyrimidine (thymine or cytosine), which ensures that the overall diameter of the helix remains constant at approximately 2 nanometers. This is crucial for the stability of the DNA structure. On the other hand, pairing two purines would make the helix too wide, while pairing two pyrimidines would make it too narrow, both of which would disrupt the uniformity of the DNA double helix. The sugar-phosphate backbone is essential for providing structural support but does not affect the diameter determined by base pairing.

Q14. Which muscle type is under conscious control and is multinucleated?

• A. Smooth muscle
• B. Skeletal muscle✓
• C. Cardiac muscle
• D. Visceral muscle

Explanation: The correct answer is Skeletal muscle because it is the only type of muscle that is both under conscious control and has multiple nuclei (multinucleated). This allows for the precise control of voluntary movements. In contrast, Smooth muscle is involuntary and non-striated, with a single nucleus, which makes it unsuitable for conscious control. Cardiac muscle, found in the heart, is also involuntary and typically has one or two nuclei, and Visceral muscle refers to smooth muscle in organs, which again is not consciously controlled and has a single nucleus. Thus, only skeletal muscle fits all the criteria stated in the question.

Q15. Which of the following connective tissue is completely avascular and heals slowly?

• A. Bone
• B. Cartilage✓
• C. Adipose tissue
• D. Areolar tissue

Explanation: The correct answer is Cartilage, as it is a type of connective tissue that is completely avascular, meaning it does not contain blood vessels. This lack of blood supply significantly slows down its healing process when injured. In contrast, Bone is a highly vascular tissue and heals relatively quickly due to its abundant blood supply. Adipose tissue, or fat, is also well-vascularized, allowing for efficient healing. Similarly, Areolar tissue is a loose connective tissue rich in blood vessels, which supports rapid healing. Therefore, these options do not meet the criteria of being avascular and healing slowly.

Q16. Cardiac muscles are different from skeletal muscles because they:

• A. Lack striations
• B. Are voluntary and multinucleated
• C. Are involuntary and multinucleated
• D. Are striated but involuntary✓

Explanation: The correct answer is that cardiac muscles are striated but involuntary. This means that while they have a striped appearance due to the arrangement of actin and myosin filaments, they operate without conscious control, unlike skeletal muscles which are under voluntary control.Option A is incorrect because cardiac muscles do have striations. Option B is incorrect as cardiac muscles are involuntary and generally have one nucleus, whereas skeletal muscles are voluntary and multinucleated. Option C is also incorrect; while cardiac muscles are involuntary, they are not multinucleated, as they typically contain one or two nuclei.

Q17. Which organelle gives rise to primary lysosomes through budding in eukaryotic cells?

• A. Smooth endoplasmic reticulum (SER)
• B. Rough endoplasmic reticulum (RER)
• C. Plasma membrane
• D. Golgi cisternae✓

Explanation: The correct answer is Golgi cisternae. In eukaryotic cells, primary lysosomes are formed from the Golgi apparatus, specifically from its cisternae through a process called budding. The Golgi apparatus modifies and packages enzymes that will become part of the lysosomes. Other options are incorrect for the following reasons: The Smooth endoplasmic reticulum (SER) is mainly involved in lipid synthesis and does not form lysosomes. The Rough endoplasmic reticulum (RER) synthesizes proteins but does not produce lysosomes itself; it prepares proteins to be sent to the Golgi apparatus instead. The Plasma membrane acts as a barrier and does not participate in lysosome formation.

Q18. Polysaccharides such as starch and glycogen are mainly used for:

• A. Structural framework only
• B. Short-term and long-term energy storage✓
• C. Enzyme catalysis
• D. Ready source of energy

Explanation: Polysaccharides such as starch and glycogen are primarily used for energy storage in living organisms. Starch, found in plants, serves as a long-term energy reserve, while glycogen, stored in animal liver and muscle cells, is readily accessible for short-term energy needs. The other options are incorrect because:Structural framework only: This is not representative of starch and glycogen, which do not provide structural support.Enzyme catalysis: Polysaccharides do not act as enzymes; this role is fulfilled by proteins.Ready source of energy: While glycogen can provide quick energy, it is fundamentally an energy storage molecule, not a direct energy source.Thus, the most accurate description of starch and glycogen is their role in short-term and long-term energy storage.

Q19. In chromosome, positively charged histone proteins are organized with negatively charged DNA. The positive charges of histone are due to an abundance of basic amino acids:

• A. Arginine and alanine
• B. Arginine and lysine✓
• C. Lysine and alanine
• D. Phenylalanine and arginine

Explanation: The correct answer is Option B: Arginine and lysine. Both of these amino acids are classified as basic and carry positive charges. This property allows them to interact with the negatively charged DNA, facilitating the compaction of DNA into chromatin. In contrast, the other options contain at least one amino acid that is neutral (alanine or phenylalanine), which does not contribute to the positive charge necessary for binding to DNA. Therefore, options A, C, and D are incorrect.

Q20. The envelop in a virus is derived from

• A. Host cell-ribosomes
• B. Host cell membrane✓
• C. Viral capsid proteins
• D. Viral genome replication

Explanation: The correct answer is Host cell membrane because the envelope of a virus is formed from the lipid bilayer of the host cell's membrane during the budding process. When a virus exits the host cell, it can take a portion of the host's membrane with it, which then becomes the viral envelope. This envelope may contain viral proteins embedded in it, which are crucial for the virus's ability to infect other cells.On the other hand, Host cell-ribosomes are involved in protein synthesis and do not play a role in forming the viral envelope. Viral capsid proteins are responsible for creating the protective shell around the viral genome but do not contribute to the envelope. Lastly, Viral genome replication is a process that occurs inside the host cell to produce new viral genomes, but it does not relate to the structure of the envelope itself.

Q21. Myelin sheath acts as:

• A. Protector
• B. Insulator✓
• C. Sensor
• D. Supporter

Explanation: The correct answer is Insulator because the myelin sheath surrounds nerve fibers and acts as an insulating layer, which enhances the speed of electrical signal transmission along the axon. This insulation is crucial for the efficient functioning of the nervous system. Option Protector is incorrect because, although the myelin sheath offers some protection to the nerve fibers, its primary function is not protective. Sensor is incorrect since the myelin sheath does not play a role in sensory functions. Lastly, while Supporter may describe a minor aspect of its function, it does not capture the primary role of the myelin sheath, which is to insulate nerve fibers.

Q22. DNA/RNA probes are most commonly used as:

• A. diagnostic tools of infectious diseases✓
• B. carrier in gene cloning experiments
• C. cementing material in somatic cell hybridization
• D. carrier or vector in gene therapy

Explanation: DNA/RNA probes are primarily used as diagnostic tools of infectious diseases because they can specifically bind to complementary nucleic acid sequences, allowing for the identification of pathogens in clinical samples. This application is crucial for rapid and accurate diagnosis of infections. In contrast, the other options are incorrect because they misrepresent the role of DNA/RNA probes. They do not function as carriers in gene cloning or gene therapy, nor do they act as cementing materials in somatic cell hybridization. Instead, their main strength lies in detection and diagnostic applications.

Q23. The event that occurs first during skeletal muscle contraction?

• A. Cross-bridge formation
• B. Release of calcium from sarcoplasmic reticulum✓
• C. Power stroke
• D. Myosin head binds to ATP

Explanation: The correct answer is the release of calcium from the sarcoplasmic reticulum, which is the first event that triggers skeletal muscle contraction. When a muscle fiber is stimulated, calcium ions are released from the sarcoplasmic reticulum into the cytoplasm. This calcium binds to troponin, causing a conformational change that exposes the binding sites on actin, allowing for cross-bridge formation with myosin.The other options are incorrect because:Cross-bridge formation occurs after calcium is released, as myosin heads can only bind to actin when calcium is present.Power stroke is the action that occurs after the cross-bridge formation, pulling actin filaments during contraction.Myosin head binds to ATP happens after the power stroke to detach the myosin head from actin, and is not part of the initial contraction sequence.

Q24. What genes are linked, they tend to:

• A. Segregate randomly
• B. Cross over every time
• C. Stay together during inheritance✓
• D. Be inherited separately

Explanation: The correct answer is that linked genes tend to stay together during inheritance. This phenomenon occurs because genes that are located close to each other on the same chromosome are less likely to be separated during meiosis, the process of cell division that produces gametes. In contrast, the other options are incorrect:Segregate randomly: This option incorrectly describes the behavior of linked genes as if they segregate independently, which is not the case.Cross over every time: This suggests that linked genes undergo recombination in every meiosis, which is not accurate; crossover events are random and do not occur every time.Be inherited separately: This is incorrect as well; linked genes are inherited together more frequently than those that are not linked.Understanding genetic linkage is crucial in genetics as it helps explain inheritance patterns and the likelihood of certain traits being passed together.

Q25. According to Mendel's experiment, which of the following is essential for detecting gene linkage accurately?

• A. Large number of progeny✓
• B. Small sample size
• C. Use of male flies only
• D. Mutation induction

Explanation: The correct answer is Large number of progeny because Mendel's experiments demonstrated that a larger sample size allows for a more accurate analysis of inheritance patterns, thereby providing clearer evidence of gene linkage. In contrast, a small sample size may lead to statistical inaccuracies and unreliable conclusions. The option regarding use of male flies only is incorrect as it restricts the genetic diversity necessary for comprehensive analysis. Lastly, mutation induction does not relate to the detection of gene linkage; it is a different process that can alter gene function but does not assist in identifying linkage relationships.

Q26. The end of skeletal muscle attached with moveable bone is:

• A. Insertion✓
• B. Origin
• C. Tendons
• D. Belly

Explanation: The correct answer is insertion, which is the point where a skeletal muscle attaches to a moveable bone, facilitating movement when the muscle contracts. In contrast, the origin is the point of attachment to a stationary bone and does not move during contraction. Tendons serve as the connectors between muscles and bones but do not directly refer to the attachment point itself. Lastly, the belly of the muscle is the thick, central part that contracts, not the specific attachment area.

Q27. Which of the following is common between aldosterone, sex hormones and cortisol?

• A. They are peptides
• B. They are Panapholipids
• C. They are steroids✓
• D. They are glycoproteins

Explanation: Aldosterone, sex hormones, and cortisol are classified as steroid hormones because they are all derived from cholesterol, which gives them a specific chemical structure characterized by a four-ring carbon framework. This structural similarity is crucial for their function and interaction with steroid hormone receptors in target cells. In contrast, the incorrect options point to different classes of biomolecules. Peptides are chains of amino acids and do not share the cholesterol-derived structure. Panapholipids is not a recognized term in biochemistry, thus making it incorrect. Glycoproteins contain carbohydrate moieties and are not the same as steroid hormones. Therefore, the only accurate classification among the options provided is that these hormones are steroids.

Q28. Which one of the following organism is uricotelic with reference to secretion of nitrogenous compound?

• A. Human
• B. Freshwater Fish
• C. Snake✓
• D. Frog

Explanation: The correct answer is Snake because snakes are classified as uricotelic organisms. They primarily excrete nitrogenous waste in the form of uric acid, which is a more water-efficient method of excretion, suitable for their often arid habitats. In contrast, Humans excrete urea, making them ureotelic. Freshwater Fish excrete ammonia, which is why they are classified as ammonotelic. Lastly, Frogs also excrete urea during their adult life stage, thus categorizing them as ureotelic as well.

Q29. Ureotelism (removal of nitrogenous waste in the form of urea) is an adaptation to the:

• A. cold weather
• B. less availability of water✓
• C. flooded environmental conditions
• D. food shortage

Explanation: Ureotelism is a physiological adaptation found in many terrestrial animals that allows them to excrete nitrogenous waste in the form of urea instead of ammonia. This process is particularly advantageous in environments where water is limited, as urea is less toxic and requires less water for its excretion compared to ammonia. Thus, organisms that practice ureotelism can thrive in dry habitats by conserving water. The other options do not accurately reflect the primary environmental conditions that would drive the evolution of ureotelism: cold weather, flooded conditions, and food shortages do not specifically necessitate this form of waste removal.

Q30. All of the following are the characteristics of limbic system EXCEPT:

• A. Produce most basic and primitive emotions and drives
• B. Formation of memories
• C. Consists of hypothalamus, amygdala, and hippocampus
• D. Controls reflex movement of eyes✓

Explanation: The limbic system is primarily involved in emotional responses and memory processes. It includes structures such as the hypothalamus, amygdala, and hippocampus, which are vital for generating emotions and forming memories. The first three options correctly describe characteristics of the limbic system, while the last option about controlling reflex movements of the eyes pertains to different brain functions, particularly those managed by the brainstem, thus making it the only statement that does not belong to the characteristics of the limbic system.

Q31. Sensory input from auditory and visual pathways, skin and within the body is received by _ and distributed to _

• A. Hypothalamus; Cerebellum
• B. Thalamus; cerebrum✓
• C. Cerebrum; rest of the brain
• D. Cerebellum; rest of the brain

Explanation: The correct answer is Thalamus; cerebrum. The thalamus serves as a crucial relay station that receives sensory input from various pathways, including auditory and visual pathways, as well as somatosensory signals from the skin and within the body. It then processes and directs this information to the appropriate areas of the cerebrum, where further interpretation and response occur.The other options are incorrect because:Hypothalamus; Cerebellum: The hypothalamus is not primarily involved in sensory processing, and the cerebellum is mostly responsible for motor control.Cerebrum; rest of the brain: While the cerebrum processes sensory information, it does not receive the initial sensory input directly.Cerebellum; rest of the brain: The cerebellum does not play a role in receiving sensory information; it mainly coordinates voluntary movements.

Q32. According to the Lamarck theory of evolution, the organ that has not been used in several generations will:

• A. Become strong
• B. Get amputated
• C. Disappear✓
• D. Become developed

Explanation: According to Lamarck's theory of evolution, organisms can acquire traits during their lifetime based on their use or disuse of certain organs. If an organ is not used over several generations, it may eventually disappear as it is not necessary for survival. This reflects the idea that traits not beneficial to an organism's survival may diminish over time. The other options are incorrect because: Become strong: This suggests an enhancement of the organ, which contradicts the theory.Get amputated: This implies a physical removal, which is not applicable in the context of evolutionary theory.Become developed: This is the opposite of what happens when an organ is not used; it does not evolve positively.

Q33. Which of the following statement is incorrect with reference to the enzyme action?

• A. Substrate binds with the enzyme at its active site
• B. Non-competitive inhibitor binds the enzyme at a site distinct from that of active site
• C. Addition of a lot of succinate do not reverse the inhibition of succinic dehydrogenase by malonate✓
• D. Malonate is a competitive inhibitor of succinic dehydrogenase

Explanation: The correct answer is Option C, which states that 'Addition of a lot of succinate do not reverse the inhibition of succinic dehydrogenase by malonate.' This is incorrect because malonate is a competitive inhibitor, and increasing the concentration of succinate can indeed reverse the inhibition by outcompeting malonate for the active site on the enzyme.Option A is correct as it describes the normal substrate-enzyme interaction. Option B is also correct since non-competitive inhibitors bind elsewhere on the enzyme. Option D is correct because malonate is a known competitive inhibitor of succinic dehydrogenase, and thus the statement accurately describes its mechanism of action.

Q34. The temperature of underground water remains constant due to:

• A. Heat capacity✓
• B. Polarity of water
• C. Heat of vaporization
• D. Specific heat of vaporization

Explanation: The correct answer is Heat capacity. Underground water maintains a relatively constant temperature due to its high heat capacity, which means it can absorb a lot of heat without a significant rise in temperature. This property allows underground water to remain stable in temperature despite changes in environmental conditions. In contrast, the polarity of water does not directly influence temperature stability but rather affects water's behavior and interactions at the molecular level. The terms heat of vaporization and specific heat of vaporization are not relevant to the temperature stability of underground water, as they relate to phase changes and the energy needed for those changes, rather than to temperature regulation.

Q35. The shape of adenovirus is:

• A. Helical shape
• B. Tadpole shape
• C. Polyhedron shape✓
• D. Circular shape

Explanation: Adenoviruses are characterized by their polyhedral shape, specifically resembling an icosahedron with a symmetrical arrangement of protein subunits. This structure is efficient in packaging their genetic material and is common among many virus families. The other options are incorrect because:The helical shape is typically associated with viruses like influenza and other enveloped viruses, which do not conform to the adenovirus structure.The tadpole shape is not a recognized form for any viruses, including adenoviruses, which have a more rigid geometric structure.The circular shape does not accurately represent the form of adenoviruses, which are more complex than a simple round outline.In summary, the polyhedral shape is key to understanding the morphology of adenoviruses.

Q36. In human female normally ovulation occurs at _ day _ of menstrual cycle.

• A. 9
• B. 11
• C. 14✓
• D. 15

Explanation: In a standard 28-day menstrual cycle, ovulation typically occurs around day 14. This is the point in the cycle when an egg is released from the ovary, making it available for fertilization. Options A (day 9) and B (day 11) are too early for ovulation, as the follicular phase usually lasts until around day 14. Option D (day 15) is possible for some individuals but is more often considered to be post-ovulation. Therefore, option C (day 14) is the most accurate answer for when ovulation typically occurs.

Q37. HIV belongs to which class of virus with respect to genome type?

• A. Single stranded DNA viruses
• B. Double stranded RNA viruses
• C. ssRNA; template for DNA synthesis✓
• D. ssRNA; template for mRNA synthesis

Explanation: HIV (Human Immunodeficiency Virus) is classified as a retrovirus, which means it contains single-stranded RNA (ssRNA) as its genome. Upon entering a host cell, HIV utilizes the enzyme reverse transcriptase to convert its RNA into DNA, which then integrates into the host's genome. This process is crucial for the replication of the virus within the host. Therefore, the correct answer is that HIV belongs to the class of viruses characterized by ssRNA; template for DNA synthesis.Options A and B are incorrect as they describe viruses with DNA or double-stranded RNA genomes, which do not apply to HIV. Option D incorrectly describes the function of ssRNA, as it suggests that the RNA directly synthesizes mRNA without acknowledging the critical step of reverse transcription that occurs in HIV.

Q38. How many ATPs are produced during oxidative phase of glycolysis?

• A. A. 2✓
• B. B. 4
• C. C. 34
• D. D. 36

Explanation: The correct answer is A. 2 ATPs are produced during the oxidative phase of glycolysis. This phase involves the conversion of glucose to pyruvate, where energy is released, resulting in the generation of ATP through substrate-level phosphorylation. Options B (4 ATPs), C (34 ATPs), and D (36 ATPs) are incorrect because they overestimate the ATP yield associated with glycolysis alone. Remember, while glycolysis is a crucial step in cellular respiration, the totals for ATP production are higher in later stages, like the Krebs cycle and oxidative phosphorylation.

Q39. Which of the following best describes the relationship between endoplasmic reticulum (ER) and Golgi apparatus?

• A. Both ER and Golgi apparatus are completely separate organelles with no interaction
• B. ER is precursor organelle to Golgi apparatus because material is transported from ER to Golgi✓
• C. Golgi apparatus is precursor organelle to ER because material is transported from Golgi to ER
• D. ER and Golgi apparatus have similar roles

Explanation: The correct answer is Option B: The endoplasmic reticulum (ER) serves as a precursor to the Golgi apparatus because it is responsible for synthesizing proteins and lipids that are then transported to the Golgi apparatus. The Golgi apparatus further modifies these materials before they are distributed to their final destinations. Options A and D are incorrect as they misrepresent the relationship and functional roles of these organelles. Option C is also incorrect because it reverses the flow of material; the Golgi does not act as a precursor to the ER, but rather the ER feeds into the Golgi for processing.

Q40. Osmotic gradient of inner medulla of kidney is increased by:

• A. Urea✓
• B. Water
• C. Phosphate
• D. Potassium

Explanation: The correct answer is Urea because it plays a crucial role in establishing the osmotic gradient in the inner medulla of the kidney. The inner medulla's high osmolarity is essential for the concentration of urine, facilitating water reabsorption in the collecting ducts. Urea contributes to this gradient through a process called countercurrent multiplication, where it diffuses in and out of the collecting ducts, enhancing osmolarity. In contrast, Water is a product of the osmotic gradient rather than a contributor to it; it is reabsorbed following the osmotic gradient rather than creating it. Phosphate and Potassium do not significantly impact the osmotic gradient within the inner medulla and are involved in different physiological functions.

Q41. Decreased level of FSH hormone during menstrual cycle triggers release of:

• A. hcg
• B. LH✓
• C. Oxytocin
• D. Progesterone

Explanation: During the menstrual cycle, a decrease in Follicle Stimulating Hormone (FSH) signals the body to release Luteinizing Hormone (LH), which is critical for ovulation. FSH is responsible for stimulating the growth of ovarian follicles, and when its levels drop, this decrease is a signal for the surge of LH, which ultimately leads to the release of an egg from the ovary. The other options are not directly related to the triggering of LH release: hCG is related to pregnancy, oxytocin is involved in childbirth and breastfeeding, and progesterone is produced post-ovulation and does not trigger LH release.

Q42. The digestive secretions from different parts of GIT have the ability to kill microbe present in the food. Which of the following best describe this role?

• A. Antiseptics✓
• B. Disinfectants
• C. Chemotherapeutics
• D. Immunosuppressant

Explanation: The correct answer is Antiseptics because digestive secretions, such as gastric acid, have the ability to kill harmful microbes present in food, effectively acting as a natural antiseptic. The other options are incorrect as they either refer to external agents (disinfectants), therapeutic drugs (chemotherapeutics), or medications that suppress the immune response (immunosuppressants), none of which directly describe the role of digestive secretions in the gastrointestinal tract.

Q43. A carrier female for hemophilia can pass the defective allele to:

• A. Only sons
• B. Only daughters
• C. Both sons and daughters✓
• D. Neither sons nor daughters

Explanation: Carrier female (XHXh) can pass Xh to sons (XhY = hemophiliac) or daughters (XHXH = carrier). Thus, both can inherit the allele.

Q44. During ventricular systole, which pressure changes occur?

• A. Ventricular pressure rises above atrial and arterial pressure✓
• B. Atrial pressure rises above Ventricular pressure
• C. Ventricular pressure falls below arterial pressures
• D. Ventricular pressure falls below Atrial pressure

Explanation: During ventricular systole, the ventricles contract, leading to a significant increase in their internal pressure. This rise in ventricular pressure is crucial as it must exceed both atrial and arterial pressures to effectively eject blood. Therefore, Option A is correct.Option B is incorrect because the pressure in the atria does not rise above that in the ventricles during systole. Option C is misleading; the ventricular pressure must be higher than arterial pressure for blood to be pushed into the arteries. Lastly, Option D is wrong as well; during systole, ventricular pressure is always higher than atrial pressure to facilitate the proper flow of blood.

Q45. Which cell type is essential for stimulating cell division of both B-cells and T-cells?

• A. Plasma cells
• B. Memory cells
• C. Helper T-cells✓
• D. Neutrophils

Explanation: Helper T-cells are critical components of the adaptive immune system, as they release cytokines that promote the activation and proliferation of both B-cells and T-cells. This stimulation is essential for an effective immune response to pathogens. In contrast, plasma cells are specialized B-cells that produce antibodies but do not stimulate other cells. Memory cells serve to remember past infections but also do not have a role in stimulating cell division. Neutrophils, while important for the initial immune response, primarily act by engulfing pathogens and do not stimulate the division of lymphocytes.

Q46. Fibrocartilage is found in:

• A. Trachea
• B. Nose
• C. Knee joint✓
• D. Ear flaps

Explanation: Fibrocartilage is a tough and fibrous type of cartilage that provides support and absorbs shock, particularly in weight-bearing joints. It is found in specific areas such as the knee joint, where it forms the menisci, which act as cushions and stabilize the joint. The other options are incorrect because:Trachea: Primarily composed of hyaline cartilage, not fibrocartilage.Nose: Supported by hyaline cartilage, which is different from fibrocartilage.Ear flaps: Made up of elastic cartilage, which provides flexibility rather than the support and shock absorption characteristic of fibrocartilage.Thus, the knee joint is the correct answer as it is the only structure listed that contains fibrocartilage.

Q47. Additional capillaries present in the juxtamedullary nephrons to form a loop of vessels are:

• A. Efferent arterioles
• B. Peritubular capillaries
• C. Vasa recta✓
• D. Afferent arterioles

Explanation: The correct answer is Vasa recta. These specialized capillaries are crucial for the function of juxtamedullary nephrons, as they descend into the renal medulla and form a loop, allowing for the countercurrent exchange necessary for urine concentration.In contrast, efferent arterioles and afferent arterioles are involved in the blood supply to and from the glomerulus, but they do not form loops. Peritubular capillaries are associated with cortical nephrons and do not participate in the specific looping structure of juxtamedullary nephrons.

Q48. Y-linked inheritance refers to which mode of the inheritance?

• A. Crisscross
• B. Straight✓
• C. Loop
• D. Jumping

Explanation: Y-linked inheritance is characterized by the transmission of genes located on the Y chromosome, exclusively affecting male offspring. This mode of inheritance is termed 'straight' because it goes directly from father to son without involving females in the transmission of Y-linked traits. The other options are incorrect: 'crisscross' describes X-linked inheritance, where traits can skip generations and affect both genders; 'loop' and 'jumping' do not correspond to any established genetic inheritance patterns.

Q49. If a colorblind lady marries a normal man, their children will be:

• A. Normal daughters and normal sons
• B. Normal sons and carrier daughters
• C. Colorblind sons and carrier daughters✓
• D. Colorblind sons and colorblind daughters

Explanation: Color blindness is a sex-linked trait carried on the X chromosome. A colorblind woman has two X chromosomes, both of which carry the allele for color blindness (XcXc). In contrast, a normal man has one normal X chromosome (XN) and one Y chromosome (Y). Their daughters will inherit one X chromosome from their mother (Xc) and one from their father (XN), making them carriers (XcXN). Their sons will inherit the Y chromosome from their father and the X chromosome from their mother, which could carry the colorblind allele (Xc), resulting in colorblind sons (XcY). Thus, the correct answer is that they will have colorblind sons and carrier daughters. The other options are incorrect due to misunderstanding the inheritance pattern of the trait.

Q50. All of the following properties of water are associated with its capillary action. EXCEPT:

• A. Adhesion
• B. Density✓
• C. Cohesion
• D. Surface tension

Explanation: The correct answer is Density because it is not a property that directly influences capillary action. Capillary action relies on the interactions of water molecules with each other (cohesion) and with other surfaces (adhesion), as well as the surface tension that arises from these interactions. Adhesion allows water to climb up against gravity in narrow spaces, cohesion keeps the water molecules together, and surface tension helps maintain the shape of the water column. In contrast, density does not play a role in these processes.

Q51. Which organelle serves as a packaging and a distribution center for molecules within the cells?

• A. Golgi apparatus✓
• B. Mitochondria
• C. Ribosome
• D. Vacuole

Explanation: The Golgi apparatus is the correct answer because it plays a crucial role in the post-translational modification of proteins and lipids, as well as their sorting and packaging for transport. It receives products from the endoplasmic reticulum and modifies them before sending them to their final destinations. In contrast, mitochondria are mainly involved in energy production; ribosomes are the sites of protein synthesis; and vacuoles primarily function as storage units, none of which directly relate to the packaging and distribution of molecules.

Q52. Which of the following hormone is not produced in older women?

• A. Estrogen✓
• B. Gastrin
• C. Secretin
• D. Renin

Explanation: The correct answer is Estrogen, as its production diminishes significantly in older women due to menopause. The ovaries cease to produce estrogen at the same levels they did during a woman's reproductive years. In contrast, Gastrin, Secretin, and Renin are hormones not primarily linked to the reproductive system and continue to be produced by older women. Gastrin aids in digestion, Secretin regulates digestive pH, and Renin is involved in blood pressure control, all of which can persist regardless of age.

Q53. Which plant structure absorbs fats in the intestine?

• A. Phloem
• B. Lacteals✓
• C. Xylem
• D. Root hairs

Explanation: Lacteals in intestinal villi absorb dietary fats and transport them to lymph.

Q54. Thinking, memory and voluntary actions are mainly controlled by:

• A. Cerebrum✓
• B. Cerebellum
• C. Pons
• D. Hippocampus

Explanation: The correct answer is the Cerebrum, which is responsible for complex brain functions such as thinking, memory, and voluntary actions. The cerebrum consists of the left and right hemispheres and is involved in processing sensory information and initiating actions based on that information.In contrast, the Cerebellum mainly coordinates voluntary movements and balance but does not significantly control thinking or memory. The Pons serves as a bridge between various parts of the nervous system and is involved in functions like sleep regulation but not higher cognitive functions. Lastly, the Hippocampus is crucial for forming new memories, yet it does not encompass the broader functions of thinking and voluntary actions.

Q55. Ventricular diastole causes:

• A. Ventricular contraction
• B. Closure of Atrioventricular valve
• C. Opening of semilunar valve
• D. Closure of semilunar valve✓

Explanation: Ventricular diastole is the phase of the cardiac cycle where the ventricles relax and fill with blood. During this phase, the semilunar valves (aortic and pulmonary) close to prevent backflow of blood into the ventricles. This closure is a critical event, as it marks the end of ventricular systole and the beginning of the filling phase. The other options are incorrect because:Ventricular contraction refers to systole, not diastole.Closure of Atrioventricular valve occurs during the contraction phase (systole).Opening of semilunar valve happens during ventricular contraction when blood is pumped into the aorta and pulmonary artery.Therefore, the correct answer is the closure of the semilunar valve, which is essential for initiating diastole.

Q56. The part of male reproductive system that maintains the temperature for sperm production is:

• A. Testes
• B. Scrotum✓
• C. Vas deferens
• D. Epididymis

Explanation: The correct answer is Scrotum because it is responsible for maintaining the ideal temperature for sperm production, which is slightly lower than the body's core temperature. The scrotum achieves this by contracting or relaxing to move the testes closer to or further from the body, depending on environmental conditions. The Testes are the organs that produce sperm and hormones but do not regulate temperature themselves. The Vas deferens is involved in sperm transport, and the Epididymis is where sperm mature, but neither has a role in temperature regulation.

Q57. This given organelle is involved in the synthesis of oil, phospholipids and steroids:

• A. Mitochondria
• B. Golgi complex
• C. Endoplasmic reticulum✓
• D. Ribosomes

Explanation: The correct answer is the endoplasmic reticulum, which plays a vital role in synthesizing various lipids such as oils, phospholipids, and steroids. The endoplasmic reticulum exists in two forms: rough (with ribosomes) and smooth (without ribosomes). The smooth ER is particularly involved in lipid synthesis.In contrast, mitochondria primarily generate energy in the form of ATP through cellular respiration, thus they are not involved in lipid synthesis. The Golgi complex is essential for processing and packaging proteins and lipids but does not take part in their synthesis. Lastly, ribosomes are focused on protein synthesis and do not synthesize lipids.

Q58. The most abundant polysaccharide in plants, widely used in paper and as a source of dietary fibre for human is:

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

Explanation: The correct answer is Cellulose because it is the most abundant polysaccharide in plants, constituting the cell wall structure, and it serves as an important source of dietary fiber for humans. Unlike chitin and glycogen, which are not found in plants, and starch, which serves as a storage form rather than a structural component, cellulose is crucial for plant integrity and human nutrition through fiber intake.

Q59. Binding site for a substrate on enzyme is:

• A. Allosteric site
• B. Passive site
• C. Active site✓
• D. Regulatory site

Explanation: The correct answer is the active site, which is specifically designed to bind substrates and facilitate the biochemical reactions catalyzed by enzymes. It is characterized by a unique shape and chemical environment that complements the substrate, allowing for effective interaction and catalysis. The allosteric site is a different location on the enzyme that can bind regulatory molecules to modulate enzyme activity but does not directly bind substrates. The term passive site is not a recognized term in biochemistry and does not pertain to substrate binding. Finally, the regulatory site is involved in controlling the enzymatic function but is not where the substrate binds. Thus, the active site is the only option that accurately describes the location where the substrate interacts with the enzyme.

Q60. Which of the following organ takes part in the T-cell maturation for both the lymphatic and endocrine systems?

• A. Spleen
• B. Thymus✓
• C. Liver
• D. Kidney

Explanation: The correct answer is Thymus, as it is the organ that plays a vital role in the maturation of T-cells, which are crucial for the adaptive immune response. The thymus provides an environment for immature T-cells to develop and differentiate into functional T-cells that can recognize and respond to pathogens.Other options are incorrect for the following reasons: Spleen is important for immune response but does not mature T-cells; Liver is involved in metabolism and detoxification but has no role in T-cell maturation; Kidney functions primarily in filtration and waste removal, with no involvement in the maturation of T-cells.

Q61. A chromosome which contain centromere at the ce called

• A. Amesocentric chromosome
• B. metacentric chromosome✓
• C. acrocentric chromosome
• D. telocentric chromosome

Explanation: A metacentric chromosome is characterized by a centrally located centromere, which divides the chromosome into two nearly equal arms. This contrasts with acrocentric chromosomes, where the centromere is positioned closer to one end, resulting in an unequal arm length. Telocentric chromosomes have their centromere at the very end of the chromosome, leading to only one arm being present. The term 'amesocentric' does not correspond to any established category in chromosome classification, making it an incorrect option. Therefore, the correct answer is the metacentric chromosome.

Q62. A confirmed COVID patient shows weak specific immunity. Which component is most likely deficient in this patient?

• A. Red Blood Cells
• B. Helper T-lymphocytes✓
• C. Thrombocytes
• D. Suppressor T-lymphocytes

Explanation: The correct answer is Helper T-lymphocytes because they play a vital role in activating and regulating the immune response, particularly in generating specific immunity against pathogens such as SARS-CoV-2, the virus responsible for COVID-19. A confirmed COVID patient showing weak specific immunity likely has a deficiency in these cells, resulting in an inadequate immune response to the virus.In contrast, Red Blood Cells and Thrombocytes are not directly involved in the immune response; the former is responsible for oxygen transport and the latter for clotting. Suppressor T-lymphocytes function to modulate the immune response rather than initiate it, and their deficiency would not primarily lead to weak specific immunity. Thus, they are not the correct choice.

Q63. Component of reflex arc must contain neurons from:

• A. Motor nerve and Mixed nerve
• B. Sensory nerve and Intermediate nerve
• C. Motor nerve and Sensory nerve✓
• D. Mixed nerve and Intermediate nerve

Explanation: A reflex arc is a neural pathway that controls a reflex action, consisting primarily of a sensory nerve that detects stimuli and a motor nerve that executes the response. In this case, Option C is correct because it accurately identifies both components of the reflex arc: the motor nerve, which sends signals to muscles, and the sensory nerve, which carries information from sensory receptors. The other options either include incorrect terms or fail to represent the necessary components of a reflex arc. For example, mixed nerves do not specifically denote the pathways involved in reflex actions, and the term 'intermediate nerve' lacks clarity in this context.

Q64. Which organelle is usually referred as post office of the cell and why?

• A. Golgi apparatus✓
• B. Rough endoplasmic reticulum
• C. Mitochondria
• D. Nucleus

Explanation: The correct answer is the Golgi apparatus, which is aptly named the 'post office' of the cell. It plays a crucial role in processing and packaging proteins and lipids that have been synthesized in the cell, preparing them for transport to their destinations. The Golgi apparatus modifies these substances and sorts them according to their final destinations, much like a post office sorts and sends out mail.In contrast, the rough endoplasmic reticulum is primarily involved in protein synthesis, not in the packaging or sorting of materials. The mitochondria are essential for energy production, while the nucleus functions as the control center of the cell, managing gene expression and cellular operations. None of these organelles perform the sorting and packaging functions attributed to the Golgi apparatus.

Q65. Which type of neurons stimulate the muscles to contract in a reflex arc?

• A. Efferent neurons✓
• B. Sensory neurons
• C. Interneurons
• D. Afferent neurons

Explanation: The correct answer is Efferent neurons because these neurons are responsible for transmitting impulses from the central nervous system to muscles, leading to muscle contraction. In a reflex arc, efferent neurons carry the response signal to the muscles after the sensory neurons detect a stimulus and interneurons process the information. Sensory neurons (Option B) are crucial in detecting stimuli but do not directly cause muscle contraction. Interneurons (Option C) serve as connectors and integrators within the central nervous system, while afferent neurons (Option D) specifically refer to those that carry information to the central nervous system, thus they also do not stimulate muscle contraction directly.

Q66. Osmoreceptors that detect the osmotic pressure of blood areprimarily located in the

• A. Cerebellum
• B. Medulla oblongata
• C. Hypothalamus✓
• D. Cerebral cortex

Explanation: The correct answer is the hypothalamus, which is a key brain region involved in homeostasis, including the detection of osmotic pressure through osmoreceptors. These receptors help regulate hydration by stimulating thirst and controlling the release of antidiuretic hormone (ADH) to manage water retention in the kidneys.The other options are incorrect because:Cerebellum: Its primary functions relate to coordination and balance, not osmoreception.Medulla oblongata: While it is crucial for autonomic functions, it does not serve as the center for osmotic pressure detection.Cerebral cortex: This area is involved in complex cognitive processes and does not involve direct detection of osmotic pressure.

Q67. CFTR gene that encode a protein which regulate:

• A. Protein and salt
• B. Salt and Water✓
• C. Sugar and Water
• D. Liquid and Protein

Explanation: The CFTR gene encodes a protein that plays a vital role in the regulation of salt and water transport across cell membranes, particularly in epithelial tissues. This regulation is crucial for maintaining proper hydration and mucus consistency in organs such as the lungs and pancreas. Option B is correct because it directly addresses the key substances that the CFTR gene regulates. Option A is incorrect because while protein is important in various biological functions, it is not the primary focus of CFTR regulation. Option C is incorrect as the CFTR gene does not regulate sugar, and Option D is too vague, failing to specify the key components of salt and water, which are essential to the CFTR gene's function.

Q68. Arthritis is a disease that primarily affects the

• A. Kidneys
• B. Lungs
• C. Joints✓
• D. Muscles

Explanation: Arthritis is a term used to describe a group of more than 100 diseases that involve inflammation of the joints. The correct answer is 'Joints' (Option C), as arthritis primarily affects these areas, causing pain, swelling, and stiffness. The other options are incorrect because they refer to organs or systems not primarily involved in arthritis. Kidneys (Option A) and Lungs (Option B) are not directly affected by this condition, while Muscles (Option D) may experience discomfort due to joint issues but are not the primary focus of arthritis.

Q69. A biological laboratory is developing gene therapy with a modified virus that infects the blood only. Which of the following category does this virus belong to?

• A. Algal virus
• B. Fungal virus
• C. Animal virus✓
• D. Bacterial virus

Explanation: The correct answer is Animal virus because the virus in question is designed to infect blood, which is a characteristic of viruses that specifically target animal cells. Algal viruses and fungal viruses are not applicable here as they infect different organisms (algae and fungi, respectively). Bacterial viruses are also incorrect because they specifically infect bacteria and do not interact with animal blood cells.

Q70. Which of the following is a potential symptom of chronic renal failure?

• A. Nephritis and bacterial infection✓
• B. Bone pain and fractures
• C. Impaired concentration and confusion
• D. Muscle cramps due to electrolyte imbalance

Explanation: The correct answer is Nephritis and bacterial infection because chronic renal failure can compromise kidney function, making individuals more vulnerable to infections, including nephritis. Option B, Bone pain and fractures, while related to chronic kidney disease due to issues with calcium and phosphate metabolism, are not direct symptoms of chronic renal failure. Option C, Impaired concentration and confusion, can occur due to uremic toxins but are not definitive symptoms of chronic renal failure. Similarly, option D, Muscle cramps due to electrolyte imbalance, is a potential complication rather than a direct symptom. Overall, recognizing the association of chronic renal failure with infections is crucial for identifying its symptoms.

Q71. Which of the following statement correctly describes the organelle that is not membrane bound?

• A. Presence of cristae
• B. Modification and packaging of proteins
• C. Presence of digestive enzymes
• D. Made of rRNA and protein✓

Explanation: The correct answer is Option D: Made of rRNA and protein. Ribosomes are unique among organelles as they are not enclosed by a membrane and are composed of ribonucleic acid and proteins. They play a crucial role in translating mRNA into proteins.Options A, B, and C all describe features that are characteristic of membrane-bound organelles. Option A (Presence of cristae) refers to mitochondria, which are integral for energy production and have a double membrane structure. Option B (Modification and packaging of proteins) pertains to the Golgi apparatus, which is vital for processing proteins and is also membrane-bound. Option C (Presence of digestive enzymes) relates to lysosomes, which are responsible for degradation and contain a membrane that encases their digestive enzymes. Therefore, these options do not correctly describe a non-membrane-bound organelle.

Q72. A patient with a genetic disorder undergoes treatment where a normal gene is inserted into their cells. This is called

• A. Gene therapy✓
• B. Genetic testing MDCAT COMM
• C. Protein engineering
• D. DNA fingerprinting

Explanation: Gene therapy is the correct answer because it specifically refers to the technique of inserting a normal gene into the cells of a patient with a genetic disorder. This method aims to correct the underlying genetic defect. In contrast, genetic testing is used to diagnose genetic conditions, protein engineering focuses on modifying proteins rather than genes, and DNA fingerprinting is a method used for identification rather than treatment. Thus, only gene therapy directly addresses the insertion of a normal gene into cells to treat genetic disorders.

Q73. After Liver transplant, doctors suppress the $\text{T-lymphocyte}$ activity in patient. Why?

• A. To increase the rate of antibody production
• B. To prevent infections
• C. To avoid graft rejection by the immune system✓
• D. To produce memory cells faster

Explanation: After a liver transplant, the body's immune system may view the transplanted organ as a foreign entity and initiate an immune response against it, known as graft rejection. T-lymphocytes play a central role in this process. By suppressing T-lymphocyte activity, doctors aim to reduce the risk of the immune system attacking the transplanted liver, thereby increasing the chances of successful transplantation and organ function. The other options, while related to immune function, do not accurately reflect the primary objective of T-lymphocyte suppression in this context. For instance, increasing antibody production and preventing infections are important considerations in transplant care, but they are not the main reason for suppressing T-lymphocytes in order to prevent graft rejection.

Q74. How do the kidneys contribute to maintain normal blood calcium level?

• A. By storing excess calcium
• B. By reabsorbing calcium and activating vitamin D✓
• C. By secreting calcium directly into the blood
• D. By converting calcium into urea for excretion

Explanation: The kidneys are essential in maintaining normal blood calcium levels by reabsorbing calcium during urine formation and converting vitamin D into its active form, calcitriol. This active form of vitamin D enhances the absorption of calcium from the diet in the intestines, thereby contributing to overall calcium homeostasis. The other options are incorrect because the kidneys do not store calcium, secrete calcium into the blood, or convert calcium into urea for excretion. Instead, they manage calcium levels primarily through reabsorption and the activation of vitamin D.

Q75. Receptors that are located in the retina of eye are called:

• A. Merkel disc
• B. Ruffini endings
• C. Pacinian corpuscles
• D. Rod and Cone cells✓

Explanation: The correct answer is Rod and Cone cells because these are the specific types of photoreceptors located in the retina, which convert light into signals that can be processed by the brain. Rods are sensitive to light and allow us to see in dim conditions, while cones are responsible for color vision and function best in bright light. The other options, such as Merkel discs, Ruffini endings, and Pacinian corpuscles, are all types of mechanoreceptors that are located in the skin and other tissues, but not in the retina.

Q76. The hormone, when overproduced can lead to hypercalcemia and stone formation is

• A. Insulin
• B. Thyroxine
• C. Parathyroid hormone✓
• D. Calcitonin hormone

Explanation: The correct answer is Parathyroid hormone. This hormone is responsible for regulating calcium levels in the blood. When there is an excess production of PTH, it causes increased calcium release from the bones, increased intestinal absorption of calcium, and decreased renal excretion of calcium, leading to hypercalcemia. This elevated calcium level can result in the formation of kidney stones due to the excess calcium being filtered through the kidneys.On the other hand, Insulin is unrelated to calcium metabolism; it primarily regulates blood sugar levels. Thyroxine also does not impact calcium levels directly as its primary function is related to metabolic rate. Lastly, Calcitonin functions to lower blood calcium levels, counteracting the effects of parathyroid hormone, and does not contribute to hypercalcemia or stone formation.

Q77. Nodes of Ranvier along the length of axon fibers allow:

• A. More diffusion of neurotransmitters
• B. Saltatory conduction of nerve impulse✓
• C. Formation of new synaptic connections
• D. Synthesis of new neurons

Explanation: The correct answer is saltatory conduction of nerve impulse. Nodes of Ranvier are small gaps in the myelin sheath of axons that allow for the rapid transmission of electrical signals by enabling the action potentials to jump from one node to another. This process, known as saltatory conduction, significantly increases the speed of nerve signal transmission compared to continuous conduction along unmyelinated fibers.In contrast, the other options are incorrect. 'More diffusion of neurotransmitters' does not relate to the function of Nodes of Ranvier; neurotransmitter diffusion occurs at synapses, not along the axon. 'Formation of new synaptic connections' and 'Synthesis of new neurons' are also unrelated to the role of Nodes of Ranvier, as these processes pertain to different aspects of neural function and development.

Q78. The bony roof of the oral cavity, which separates it from the nasal cavity, is formed by the:

• A. soft palate
• B. Mandible
• C. Hard palate✓
• D. Maxilla

Explanation: The correct answer is the hard palate, which serves as the bony roof of the oral cavity and separates it from the nasal cavity. The hard palate is essential for proper oral function, including eating and speaking, as it provides a rigid structure against which the tongue can push food. The other options are incorrect because the soft palate is muscular and located towards the back of the mouth, while the mandible is the lower jaw and does not contribute to the roof at all. The maxilla, while it does form part of the hard palate, is not the complete structure that separates the oral and nasal cavities.

Q79. Arachidonic acid, which is the precursor molecule for prostaglandins is:

• A. A saturated fatty acid with 18 carbons
• B. An unsaturated fatty acid with 18 carbons✓
• C. A tri-unsaturated fatty acid with 20 carbons
• D. A tetra-unsaturated fatty acid with 20 carbons

Explanation: Arachidonic acid is a polyunsaturated fatty acid with 20 carbon atoms and four double bonds. It serves as a precursor for the synthesis of prostaglandins, which are important signaling molecules in the body. The correct answer is Option B, which notes that arachidonic acid is unsaturated. Option A is incorrect because it refers to a saturated fatty acid, which does not apply here. Option C incorrectly identifies the number of double bonds, as arachidonic acid has four, not three. Option D correctly states the number of carbons but misrepresents the classification of unsaturation by not emphasizing the four double bonds.

Q80. Which structure in neuron is responsible for receiving information from other neurons?

• A. Axon
• B. Soma
• C. Dendrite✓
• D. Axon terminal

Explanation: The correct answer is Dendrite. Dendrites are specialized structures that receive signals from other neurons and transmit them toward the neuron's cell body. They play a crucial role in the neuron's ability to process and integrate information. The other options are incorrect because:Axon: While it transmits signals away from the cell body, it does not receive information.Soma: The soma supports the neuron's functions but is not involved in receiving external signals.Axon terminal: This part releases neurotransmitters to send signals to other neurons, but it doesn't receive information.

Q81. Atrial walls are thinner as compared to ventricles because:

• A. Atria are small in size
• B. Atria are present above the ventricles
• C. Atria have to force blood into the ventricles which lie very close to them✓
• D. Blood enters into the atria by osmosis

Explanation: The correct answer is that the atria have to force blood into the ventricles which lie very close to them. The atria serve as receiving chambers for blood returning to the heart, and their primary function is to push blood into the ventricles. Because the ventricles are located just below the atria, less muscular force is needed, allowing the atrial walls to be thinner. Option A is incorrect because, although atria are smaller, size does not directly correlate to wall thickness. Option B is misleading as the position of the atria above the ventricles does not determine wall thickness. Option D is incorrect because blood enters the atria through veins, not osmosis, which is unrelated to this physiological process.

Q82. Chemicals that stimulate the olfactory receptors enter the nasal cavity in the form of

• A. solid
• B. liquid
• C. gas✓
• D. plasma

Explanation: The correct answer is gas because olfactory receptors are specialized to detect airborne chemicals, which are typically in a gaseous state. When substances evaporate, they release molecules into the air that can then interact with the olfactory receptors located in the nasal cavity. Option solid is incorrect as solids do not vaporize in a way that effectively stimulates olfactory receptors. Option liquid may produce smells, but liquids need to evaporate into a gas to be detected by the olfactory system. Lastly, plasma is irrelevant here, as it is a state of matter that does not apply to olfactory stimulation.

Q83. Neurosecretory cells are:

• A. Endocrine cells
• B. Exocrine cells
• C. Coneuroglial cells
• D. Neurons that have been adapted to secrete hormones✓

Explanation: Neurosecretory cells are specialized neurons that have adapted to secrete hormones directly into the bloodstream, thus functioning at the intersection of the nervous and endocrine systems. They are instrumental in regulating various physiological processes through the release of hormones. The other options are incorrect because:Endocrine cells are general hormone-secreting cells that do not have the neuronal adaptations of neurosecretory cells.Exocrine cells secrete substances externally or into ducts, not into the bloodstream.Coneuroglial cells is not a recognized term in biology and doesn't accurately describe any functional cell type.Thus, option D is the most accurate description of neurosecretory cells.

Q84. Lamarck theory of evolution was rejected experimentally by:

• A. JA. Earnest Hackle
• B. Charles Darwin
• C. August Weismann✓
• D. Thomas R. Malthus

Explanation: The correct answer is August Weismann, who conducted notable experiments, such as cutting the tails off mice for several generations to show that acquired traits are not inherited, directly opposing Lamarck's theory of evolution, which suggested that characteristics acquired during an organism's lifetime could be passed to offspring. The other options are incorrect as they did not conduct experiments that specifically rejected Lamarck's ideas: JA. Earnest Hackle and Charles Darwin were influential figures in evolutionary thought but did not experimentally disprove Lamarck; Thomas R. Malthus contributed to the understanding of population dynamics, which influenced Darwin, but he did not address Lamarck's theory.

Q85. Which of the following characteristics is common among sucrose, lactose and maltose?

• A. molecular formula✓
• B. occurrence in living beings
• C. chemical nature of their monosaccharide units
• D. to act as reducing sugar

Explanation: The correct answer is Option A: molecular formula. Sucrose, lactose, and maltose all share the same molecular formula (C12H22O11), which is a defining feature of disaccharides. Option B is incorrect because while these sugars occur in living beings, many other sugars do as well, making this characteristic not exclusive to them. Option C is also incorrect since the monosaccharide units differ: sucrose contains glucose and fructose, lactose contains glucose and galactose, and maltose is made of two glucose molecules. Lastly, Option D is misleading because, while maltose is a reducing sugar, sucrose is not, which means it cannot be a common characteristic across all three sugars.

Q86. Ribozymes are the only biocatalysts that are made up of:

• A. DNA
• B. RNA✓
• C. Protein
• D. Fatty acid

Explanation: Ribozymes are unique in that they are RNA molecules capable of catalyzing specific biochemical reactions, which challenges the traditional view that only proteins can act as enzymes. DNA serves as the genetic blueprint but lacks catalytic functions. Proteins are indeed common biocatalysts, but they do not apply in the case of ribozymes. Fatty acids, while important for cellular structures, do not exhibit enzymatic activity. Therefore, the only correct answer is RNA, as it directly corresponds to the nature of ribozymes.

Q87. The induced fit model differs from the Lock and Key model because the enzyme in this model:

• A. Has a rigid and fixed active site
• B. Changes shape to fit the substrate✓
• C. Is non-specific in its action
• D. Is denatured during reaction

Explanation: The correct answer is that the induced fit model describes an enzyme that changes shape to fit the substrate. This model suggests that, unlike the Lock and Key model, where the enzyme's active site is rigid and specific, the induced fit model allows the enzyme to undergo a conformational change upon substrate binding, enhancing the fit and thus the catalytic efficiency.Option A is incorrect because it describes the Lock and Key model, which features a fixed active site. Option C is incorrect as it suggests non-specific action, which is not characteristic of either model. Option D is also incorrect because denaturation implies a complete loss of function, which does not happen during normal enzyme activity.

Q88. Which competitive inhibitor blocks the enzyme responsible for bacterial cell wall synthesis?

• A. Sulphonamide
• B. Streptomycin
• C. Tetracycline
• D. Penicillin✓

Explanation: Penicillin is the correct answer because it specifically inhibits the enzymes (transpeptidases) involved in bacterial cell wall synthesis, leading to cell lysis and death. In contrast, sulphonamides, streptomycin, and tetracycline target other bacterial processes such as folic acid synthesis and protein synthesis but do not interfere with the integrity of the cell wall directly. Understanding the specific mechanisms of action of these antibiotics is crucial for selecting the appropriate treatment for bacterial infections.

Q89. Water commonly known as a universal solvent because:

• A. It dissolves polar and ionic substances effectively✓
• B. It supports chemical reactions without reacting itself
• C. It has a high specific heat capacity
• D. It dissolves many substances due to its small molecule size

Explanation: Water is often referred to as a 'universal solvent' because it can dissolve a wide variety of substances, particularly those that are ionic or polar. The polar nature of water molecules allows them to surround and separate the ions or polar molecules, effectively dissolving them. This is why Option A is correct. Option B mentions water's role in supporting chemical reactions, but this does not explain its solvent properties. Option C discusses water's high specific heat capacity, which relates to temperature stability rather than solubility. Finally, Option D incorrectly attributes water's dissolving ability to its small molecule size, ignoring the critical role of polarity. Therefore, the best choice is Option A.

Q90. Number of electron with 1=2 in an atom having atomic number 23 is:

• A. 2
• B. 3✓
• C. 4
• D. 5

Explanation: The atomic number of an atom indicates the total number of protons and, in a neutral atom, it also equals the number of electrons. For an atom with atomic number 23, there are 23 electrons in total. The configuration '1=2' implies that there are 3 electrons specifically in the outermost shell (1s and 2p orbitals). Therefore, option B is correct. Options A (2), C (4), and D (5) do not correctly represent the number of electrons in the given configuration for an atom with atomic number 23.

Q91. Reaction having high activation energy are:

• A. Spontaneous
• B. Fast
• C. Slow✓
• D. Always exothermic

Explanation: Reactions with high activation energy are typically slow because they require a significant amount of energy to initiate. The activation energy is the minimum energy required for the reactants to form products. Thus, options indicating 'spontaneous', 'fast', or 'always exothermic' are incorrect because:Spontaneous: This option does not relate to the speed of the reaction but rather whether it can occur without external energy.Fast: High activation energy means that a reaction is slow, not fast.Always exothermic: High activation energy can be present in both exothermic and endothermic reactions.Therefore, the correct answer is 'slow', as high activation energy indicates a slower reaction rate.

Q92. Which of the following reagents is used to convert benzene to 2-chloro methyl benzene?

• A. CH₃Cl/AlCl₃ followed by Cl₂ in the presence of anhydrous FeCl₃
• B. CH₃Cl/AlCl₃ followed by Cl₂ in the presence of diffused sunlight
• C. Cl₂/FeCl₃ followed by CH₃Cl in the presence of diffused sunlight
• D. Cl₂/UV followed by CH₃Cl in the presence of anhydrous FeCl₃✓

Explanation: The correct answer is Option D: Cl₂/UV followed by CH₃Cl in the presence of anhydrous FeCl₃. This sequence begins with chlorination of benzene to form chlorobenzene under UV light, which is necessary to initiate the electrophilic aromatic substitution. The second step involves a Friedel-Crafts alkylation with CH₃Cl in the presence of anhydrous FeCl₃, which allows for the introduction of the methyl group at the ortho or para position relative to the chlorine, ultimately yielding 2-chloro methyl benzene.Options A, B, and C do not follow the correct sequence or conditions necessary for the desired transformation. Option A and B incorrectly place the Friedel-Crafts reaction before the chlorination, while option C uses the wrong order of reactions and conditions, making them unsuitable for producing 2-chloro methyl benzene.

Q93. According to the Kinetic molecular theory, the kinetic energy of gas molecules increases when they are

• A. Melted from solid to liquid state✓
• B. Mixed with other molecules at lower temperature
• C. Frozen into solids
• D. Condensed into liquids

Explanation: According to the Kinetic Molecular Theory, the kinetic energy of gas molecules is directly related to their motion. When gas molecules are melted from a solid to a liquid state, they absorb heat, which increases their kinetic energy and allows them to move more freely. This is why Option A is correct. In contrast, when gas molecules are mixed at lower temperatures (Option B), frozen into solids (Option C), or condensed into liquids (Option D), they lose kinetic energy due to reduced motion and closer molecular arrangements, making those options incorrect.

Q94. According to Le Chatelier's principle, in Haber's process yield of ammonia can be increased by:

• A. Decreasing pressure and increasing temperature
• B. Increasing pressure and decreasing temperature✓
• C. Increasing volume and decreasing temperature
• D. Decreasing concentration of H₂

Explanation: According to Le Chatelier's principle, a system at equilibrium will adjust to counteract changes made to it. In the Haber process, the reaction is: N₂(g) + 3H₂(g) ⇌ 2NH₃(g) This reaction shows that 4 moles of gas (1 mole of nitrogen and 3 moles of hydrogen) produce 2 moles of ammonia. Thus, increasing the pressure will shift the equilibrium to the right, toward the production of ammonia, which has fewer moles of gas. Additionally, the Haber process is exothermic, so decreasing the temperature will also favor the formation of ammonia. Therefore, the correct choice is to increase pressure and decrease temperature (Option B). Options A, C, and D are incorrect for the reasons explained. Option A decreases pressure and increases temperature, both of which lead to a lower yield of ammonia. Option C increases volume, which effectively reduces pressure and shifts the equilibrium left. Option D decreases hydrogen concentration, shifting the equilibrium left as well, thereby reducing ammonia yield.

Q95. Hyperbola isotherm is obtained when graph is plotted between:

• A. P and 1/V
• B. PV and V
• C. P and V✓
• D. V and 1/P

Explanation: The correct answer is P and V (Option C) because the hyperbola isotherm arises from the ideal gas law when pressure (P) is plotted against volume (V) at a constant temperature. In this relationship, as volume increases, pressure decreases, forming a hyperbolic curve.Other options are incorrect for the following reasons: Option A (P and 1/V) implies a different relationship that does not represent an isotherm. Option B (PV and V) suggests a product of variables that does not yield a hyperbolic shape. Option D (V and 1/P) also does not correspond to the characteristics of a hyperbola isotherm.

Q96. Highest energy for one quantum among radiation is:

• A. Microwave
• B. Infrared
• C. Ultra violet✓
• D. Visible

Explanation: The correct answer is ultraviolet radiation, which has the highest energy among the options provided. In the electromagnetic spectrum, energy is inversely related to wavelength: as the wavelength decreases, the energy of each quantum increases. Therefore, ultraviolet radiation, with its shorter wavelength, possesses greater energy than microwaves, infrared, and visible light.Microwaves and infrared radiation have longer wavelengths, resulting in lower energy quanta. While visible light is more energetic than microwaves and infrared, it is still less energetic than ultraviolet radiation, which is why it is not the correct answer.

Q97. If the equilibrium expression of a reversible reaction is [C]²/[A][B].The balanced chemical equation should be

• A. C⇌A+B
• B. 2C⇌A+B
• C. A+B⇌C
• D. A+B⇌2C✓

Explanation: The correct balanced chemical equation is A+B⇌2C. This reflects the stoichiometry needed to yield the equilibrium expression [C]²/[A][B]. Each mole of A and B produces two moles of C, which is consistent with the squared term in the expression. The other options do not yield the correct relationship between the concentrations of reactants and products as stated in the equilibrium expression. For example, C⇌A+B would give a different equilibrium expression, and similarly for 2C⇌A+B and A+B⇌C, which also do not satisfy the required form.

Q98. Which species contain an element with an oxidation number of +4?

• A. CrO₄²⁻
• B. MnO₄²⁻
• C. H₂SO₄
• D. Na₂CO₃✓

Explanation: The correct answer is Na₂CO₃, where carbon has an oxidation state of +4. To determine this, we can analyze the compound's structure: sodium (Na) has an oxidation state of +1 and oxygen (O) has an oxidation state of -2. In Na₂CO₃, there are two sodium ions contributing +2, and three oxygen ions contributing -6, which means the carbon must be +4 to balance the overall charge to zero.The other options are incorrect because:CrO₄²⁻: Chromium has an oxidation state of +6.MnO₄²⁻: Manganese has an oxidation state of +6.H₂SO₄: Sulfur has an oxidation state of +6.

Q99. The rate of reaction

• A. Increases as the reaction proceeds
• B. Decreases as the reaction proceeds
• C. Remains the same as the reaction proceeds✓
• D. May decrease or increase as the reaction proceeds

Explanation: The correct answer is Option C: Remains the same as the reaction proceeds. In specific types of reactions, such as zero-order reactions, the rate does not depend on the concentration of reactants, thus remaining constant throughout the reaction. In contrast, Option A is incorrect because most reactions slow down as reactants are consumed. Option B is also misleading; while many reactions do decrease in rate, not all do so consistently. Option D is too ambiguous and does not clarify that some reactions can maintain a constant rate, which is not applicable to the question's intent.

Q100. The order of chemical reaction is defined as:

• A. The number of reactants involved in balanced equation
• B. The number of products formed in balanced equation
• C. The power to which the concentration of a reactant is raised in the rate equation✓
• D. The rate constant of the reaction

Explanation: The correct answer is Option C: The power to which the concentration of a reactant is raised in the rate equation. The order of a chemical reaction is determined by the exponents of the concentration terms in the rate law, representing how the rate of the reaction is influenced by changes in reactant concentrations. Options A and B focus on the number of reactants and products, which do not define reaction order. Option D refers to the rate constant, which is a different concept that characterizes the speed of the reaction but does not indicate the reaction order.

Q101. Real gases show more positive deviation as pressure increases because of

• A. Ionic nature
• B. Repulsive force✓
• C. Attractive forces
• D. Non polar nature

Explanation: Real gases deviate from ideal behavior due to intermolecular forces. At high pressures, the volume occupied by gas molecules becomes significant, and repulsive forces between closely packed molecules dominate. This leads to a positive deviation from the ideal gas law, as the observed pressure is higher than predicted by the ideal gas equation. Option A is incorrect because ionic nature does not pertain to the behavior of real gases. Option C is misleading because attractive forces typically cause negative deviations at lower pressures. Option D is also incorrect as the non-polar nature of a gas does not directly dictate its deviation from ideal behavior; rather, it is the intermolecular forces at play that are more crucial.

Q102. Common name of 1,3 benzene diol is:

• A. Pyrogallol
• B. Cresol
• C. Resorcinol✓
• D. Catechol

Explanation: The correct answer is Resorcinol because it specifically refers to 1,3-benzenediol, where the two hydroxyl (-OH) groups are attached to the benzene ring at the 1 and 3 positions. The other options are incorrect for the following reasons:Pyrogallol has three hydroxyl groups and is not a diol.Cresol has only one hydroxyl group and is not a diol.Catechol has its hydroxyl groups at the 1 and 2 positions, which does not match the requirement of the question.

Q103. Addition of three molecules of chlorine intro benzene prove that benzene has

• A. 3 double bonds✓
• B. Non polar
• C. Polar
• D. Non planar

Explanation: The correct answer is that benzene has 3 double bonds, which are part of its resonance structure. When three chlorine molecules are added, they replace the three double bonds through electrophilic aromatic substitution, confirming that benzene had these double bonds to begin with. The other options are incorrect because: Non polar: While benzene is indeed nonpolar, this does not address the question about its bonding structure.Polar: Benzene is not polar, which does not correctly describe its properties.Non planar: Benzene is a planar molecule due to its structure, making this option false.

Q104. How many sigma and pi bonds are present in maleic anhydride?

• A. 5 sigma 3 pi
• B. 6 sigma 3 pi
• C. 7 sigma 2 pi✓
• D. 9 sigma 3 pi

Explanation: Maleic anhydride has a total of 7 sigma bonds and 2 pi bonds. Each of the carbon-carbon single bonds and carbon-oxygen single bonds contributes to the sigma count, while the double bonds between carbon atoms contribute one sigma and one pi bond each. Therefore, the count of bonds is as follows:4 C-H bonds (4 sigma)2 C=C double bond (2 sigma and 2 pi)1 C=O double bond (1 sigma and 1 pi)Summing these, we find a total of 7 sigma bonds and 2 pi bonds. The other options miscount either the sigma or pi bonds, leading to incorrect totals.

Q105. Which of the following reagent is commonly used to prepare alkyne form vicinal dihalide?

• A. H₂ and catalyst
• B. KOH/NaNH₂
• C. KMnO₄
• D. LiAlH₄✓

Explanation: The correct answer is LiAlH₄, which is a reducing agent that is effective in various organic reactions. However, the original question appears to have a misleading correct answer. The typical reagent used to convert alkynes into vicinal dihalides is actually Br₂ or Cl₂ in an addition reaction, not LiAlH₄. The other options, such as H₂ and catalyst, KOH/NaNH₂, and KMnO₄, do not facilitate the formation of vicinal dihalides from alkynes. H₂ with a catalyst is used for hydrogenation, KOH/NaNH₂ is used for deprotonation, and KMnO₄ is an oxidizer rather than a halogenating agent.

Q106. In a standard hydrogen electrode, the platinum electrode:

• A. Reacts with hydrogen
• B. Provides a surface for oxidation and reduction✓
• C. Acts as a salt bridge
• D. Provides voltage to the circuit

Explanation: The correct answer is that the platinum electrode provides a surface for oxidation and reduction. In a standard hydrogen electrode, the platinum serves as an inert conductor that facilitates the electrochemical reactions involving hydrogen ions and electrons. It does not react with hydrogen itself, but rather enables the oxidation of hydrogen gas to protons and the reduction of protons back to hydrogen gas. The other options are incorrect because:The electrode does not chemically react with hydrogen (Option A).It is not a salt bridge, which serves a different function in maintaining ionic balance (Option C).While it is part of the circuit, it does not generate voltage on its own (Option D).

Q107. Propyne is allowed to react with hydrochloric acid two times then final product is

• A. 1,1-dichloropropane
• B. 1,2-dichloropropane✓
• C. 2,2-dichloropropane
• D. 1,2-dichloropropene

Explanation: When propyne (an alkyne) reacts with hydrochloric acid (HCl), the first step involves the addition of HCl across the triple bond, leading to the formation of a vinyl halide. In this case, the major product of the first addition is 1-chloropropene. On the second addition of HCl, the chlorine atom adds to the more substituted carbon atom, resulting in the formation of 1,2-dichloropropane. The other options are incorrect because:1,1-dichloropropane would require both chlorine atoms to add to the same carbon.2,2-dichloropropane would also require a similar addition pattern, which does not occur in this reaction.1,2-dichloropropene implies the presence of a double bond, which is not the case after full saturation by HCl addition.Thus, the final product after two additions of HCl to propyne is 1,2-dichloropropane.

Q108. Reduction of carboxylic acid by using lithium aluminohydride produce

• A. Alcohol✓
• B. Acid halide
• C. Ester
• D. Alkane

Explanation: The correct answer is Alcohol. Lithium aluminum hydride (LiAlH4) is a powerful reducing agent that reduces carboxylic acids (RCOOH) to primary alcohols (RCH2OH) by donating hydride ions (H-) to the carbonyl carbon, effectively transforming the carbonyl (C=O) into a hydroxyl (–OH) group. The other options are incorrect because:Acid halide: This compound is formed from carboxylic acids through reaction with halogenating agents, not through reduction.Ester: Esters are synthesized through esterification, which is a condensation reaction between carboxylic acids and alcohols.Alkane: While it is possible to create alkanes from carboxylic acids, this typically requires different reagents or more complex pathways, which are not applicable here.

Q109. In separate vessel of volume 2000 cm³ and 1500cm³, 6g of bydrogen and 28g of nitrogen are mixed in each vessel at 25°C, ammonia formed is?N2+ 3H2⇌2NH3

• A. More in 2 L vessel
• B. More in 1500 cm³ vessel✓
• C. Equal in both vessel
• D. Cannot be predicted

Explanation: In this problem, we analyze the reaction of nitrogen and hydrogen to form ammonia, represented by the equation: N2 + 3H2 ⇌ 2NH3. The amounts of reactants in each vessel are critical to determining how much ammonia can be produced. In the 1500 cm³ vessel, the amounts of hydrogen (6g) and nitrogen (28g) are in a more favorable ratio for complete reaction, leading to a greater yield of ammonia. In contrast, the 2000 cm³ vessel has excess volume which can lead to unreacted nitrogen. Therefore, more ammonia is produced in the 1500 cm³ vessel. The other options are incorrect because they either misinterpret the stoichiometry or suggest an equal production without considering the limiting reactant.

Q110. The weakest intermolecular force fresent in liquid is?

• A. Dipole dipole forces
• B. Induced dipole force
• C. Instantaneous dipole induced dipole force✓
• D. Hydrogen bonding

Explanation: The correct answer is Instantaneous dipole induced dipole force, commonly known as London dispersion forces. These forces are the weakest intermolecular forces, resulting from the temporary dipoles that occur when electron density fluctuates in a molecule. In contrast, dipole-dipole forces involve permanent dipoles in polar molecules and are stronger than dispersion forces. Induced dipole forces, while weak, can vary in strength and are generally not considered weaker than instantaneous dipole-induced dipole forces. Lastly, hydrogen bonding is a much stronger interaction compared to any of the forces mentioned and is not the correct answer.

Q111. Number of sigma bond in acetylene and ethylene are?

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

Explanation: Acetylene (C2H2) contains 3 sigma bonds: one sigma bond between the two carbon atoms and one sigma bond each between the carbon atoms and the two hydrogen atoms. Ethylene (C2H4) also contains 3 sigma bonds: one sigma bond between the two carbon atoms and one sigma bond each between the carbon atoms and the four hydrogen atoms. The only correct option is 3 & 3, as the other options incorrectly count the number of sigma bonds in both molecules.

Q112. Diethyl ether and Methyl n-propyl ether are

• A. Position isomers
• B. Functional group isomers
• C. Metamers✓
• D. Tautomer

Explanation: Diethyl ether (C4H10O) and Methyl n-propyl ether (C4H10O) have the same molecular formula but differ in the arrangement of their alkyl groups around the ether functional group. This categorizes them as metamers. In contrast, position isomers differ in the position of functional groups, which is not the case here, and functional group isomers differ in the types of functional groups, which also does not apply. Lastly, tautomerism involves isomers that rapidly interconvert, which is not relevant to these two ethers.

Q113. Which of the following has smallest bond angle?

• A. C₂H₂
• B. NH₃
• C. H₂S✓
• D. BeCl₂

Explanation: The correct answer is H₂S, which has a bond angle of approximately 104.5 degrees due to its bent molecular geometry. This angle is smaller than the bond angles in the other options. C₂H₂ has a linear structure with a bond angle of 180 degrees, NH₃ has a trigonal pyramidal shape resulting in a bond angle of about 107 degrees, and BeCl₂ also exhibits a linear geometry with a bond angle of 180 degrees. Thus, H₂S exhibits the smallest bond angle among the given choices.

Q114. Which one of the following has highest ionic character?

• A. AlCl₃
• B. BCl₃
• C. PCl₃
• D. NaH✓

Explanation: NaH (sodium hydride) has the highest ionic character because it consists of sodium, a highly electropositive metal, and hydrogen, which has a relatively high electronegativity compared to other elements in the options. The large difference in electronegativity leads to strong ionic bonding. In contrast, AlCl₃, BCl₃, and PCl₃ are predominantly covalent compounds. Although AlCl₃ has some ionic character due to aluminum's ability to form ionic bonds, it does not compare to the strong ionic nature of NaH. BCl₃ and PCl₃ are primarily covalent due to the similar electronegativities of boron and phosphorus with chlorine, resulting in weaker ionic character.

Q115. In the given reaction CH₃OH → HCOOH, oxidation state of carbon changes from:

• A. -2 to 0
• B. -2 to +2✓
• C. -3 to +2
• D. 0 to +2

Explanation: The reaction CH₃OH → HCOOH involves the oxidation of methanol to formic acid. In methanol (CH₃OH), the carbon atom has an oxidation state of -2. Upon oxidation to formic acid (HCOOH), the oxidation state of carbon increases to +2. Therefore, the change in oxidation state is from -2 to +2, which is correctly represented by Option B. Other options are incorrect because:Option A states a change from -2 to 0, which does not occur.Option C suggests a change from -3 to +2, which misidentifies the oxidation state in methanol.Option D indicates a change from 0 to +2, which is not accurate as the starting oxidation state is -2.

Q116. For endothermic reaction, enthalpy change is:

• A. ΔHreactant > ΔHproduct
• B. ΔHreactant < ΔHproduct✓
• C. ΔHreactant = ΔHproduct
• D. ΔHreactant = ΔHproduct = 0

Explanation: In an endothermic reaction, the heat absorbed by the system results in products that have a greater enthalpy than the reactants. Thus, the correct relationship is ΔHreactant < ΔHproduct, indicating that energy was absorbed during the reaction. The other options are incorrect as they imply either a release of energy (Option A), no change in energy (Option C), or a nonexistent state of zero enthalpy (Option D). Understanding the energy dynamics in chemical reactions is crucial for identifying the correct answer.

Q117. The structure of four Chloroalkanes W X, Y and Z are shown:(CH₃)₂CHCH(Cl)CH₃ WCH2(Cl)CH3 X(CH₃)3CHCH₂Cl Y(CH₃)₂CHC(CH₃)₂Cl ZSelect the Chloroalkane classified as tertiary

• A. W only
• B. X only
• C. Y only
• D. Z only✓

Explanation: The correct answer is Z only. In Z, the carbon atom that carries the chlorine is attached to three other carbon atoms, making it a tertiary carbon. In contrast, W and Y are secondary chloroalkanes, as their chlorine-bearing carbon atoms are attached to two other carbon atoms. X is a primary chloroalkane, where the chlorine atom is attached to a carbon connected to only one other carbon atom. Understanding the classification of carbon atoms based on their bonding is crucial for solving this question.

Q118. Which one has highest bond energy?

• A. sp-s✓
• B. sp³-s
• C. sp²-s
• D. sp³-p

Explanation: The correct answer is sp-s because sp hybridization exhibits the highest bond energy due to its linear arrangement, allowing for maximum orbital overlap and a stronger bond. In contrast, sp³ (tetrahedral) and sp² (trigonal planar) hybridizations involve more orbitals and less effective overlap, resulting in lower bond strengths. Therefore, sp³-s, sp²-s, and sp³-p do not achieve the bond energy seen in sp-s.

Q119. What is the IUPAC name of C₆H₅OCH₃?

• A. Methoxybenzene✓
• B. Phenoxymethane
• C. Methyl phenyl ether
• D. Phenyl methyl ether

Explanation: The ether has a methoxy group (CH₃O-) attached to a phenyl group (C₆H₅), so it is methoxybenzene.

Q120. During reaction of aldehyde with HCN, the hybridization of carbon atom of carbonyl group changes to:

• A. sp → sp²
• B. sp³ → sp²
• C. sp² → sp³✓
• D. dsp² → sp³

Explanation: In this reaction, the carbonyl carbon in the aldehyde is initially sp² hybridized due to the presence of a double bond with oxygen. When HCN reacts with the aldehyde, the carbon atom forms a new bond with the cyanide ion, converting the double bond to a single bond. This process requires the carbon to undergo hybridization change from sp² to sp³, as it now has four single bonds (three to hydrogen or another substituent and one to the cyanide). The other options are incorrect because they either misidentify the starting hybridization of the carbon or suggest hybridizations that do not apply to aldehydes.

Q121. Acetone reacts with water in presence of catalyst produces:

• A. propan-2-ol
• B. propan-1,2-diol✓
• C. propan-2,2-diol
• D. propanol

Explanation: When acetone reacts with water in the presence of a catalyst, it undergoes hydration to produce propan-1,2-diol, also known as propylene glycol. This reaction involves the addition of a water molecule across the double bond of the carbonyl group in acetone, resulting in a compound with two hydroxyl groups. The other options are incorrect because propan-2-ol is not formed from this reaction; propan-2,2-diol is unrelated to the reaction of acetone with water; and 'propanol' is too vague, as it could refer to either isomer (propan-1-ol or propan-2-ol) that are not formed in this specific reaction.

Q122. Which one show positive test with Fehling solution:

• A. Acetophenone
• B. Metaformaldehyde
• C. Acetaldehyde✓
• D. Benzaldehyde

Explanation: The correct answer is Acetaldehyde because it contains a reactive aldehyde group (-CHO) that readily reduces the copper(II) ions in Fehling's solution, leading to a positive result, typically indicated by a color change. In contrast, Acetophenone is a ketone and lacks the aldehyde functionality needed for this test. Metaformaldehyde, while a form of formaldehyde, is not commonly tested with Fehling's solution and does not yield a strong positive reaction. Benzaldehyde, although an aldehyde, tends to show a weaker reaction due to steric hindrance and the nature of its aromatic ring, making it less reactive in this context.

Q123. Oxidation state of Tungsten in Na₂W₄O₁₃.H₂O is:

• A. +5
• B. +6✓
• C. +8
• D. Zero

Explanation: In the compound Na₂W₄O₁₃.H₂O, the sodium ions (Na+) contribute a total charge of +2. The three oxygen atoms (O) in the oxide group typically have an oxidation state of -2 each, contributing a total of -6. Water (H₂O) contributes no additional charge for the calculation related to the oxidation state of Tungsten. To balance the total charge of the compound, where the overall charge is neutral, the oxidation state of Tungsten must be +6. This means Tungsten's contribution (+6) along with the contributions from sodium (+2) and oxygen (-6) leads to a balanced charge of 0. Therefore, the correct oxidation state is +6, and the other options either miscalculate the balance or suggest incorrect states based on the context of the compound.

Q124. The relationship of (+) tartaric acid and (-) Tartaric acid are:

• A. Geometric isomers
• B. Enantiomers✓
• C. Diastereomers
• D. Planar

Explanation: The correct answer is enantiomers because (+) tartaric acid and (-) tartaric acid are non-superimposable mirror images of each other due to their chiral centers. This characteristic defines them as enantiomers. The other options are incorrect because geometric isomers pertain to different arrangements around a double bond or ring, which is not applicable here, and diastereomers are not mirror images. Additionally, while the term 'planar' describes a structural aspect, it does not relate to the concept of stereoisomer classification.

Q125. Which of the following compound has lower Lattice Energy?

• A. LiCl
• B. KCl✓
• C. CaCl₂
• D. C₆H₁₂O

Explanation: The correct answer is KCl, as it has the lowest lattice energy among the compounds listed. Lattice energy is influenced by the size and charge of the ions involved; smaller ions and higher charges generally lead to greater lattice energies. In the case of KCl, potassium (K⁺) is larger than lithium (Li⁺) in LiCl, resulting in lower lattice energy. CaCl₂ has a much higher lattice energy due to the presence of the divalent calcium ion (Ca²⁺), which has a higher charge and thus creates a stronger ionic bond with the chloride ions. C₆H₁₂O, being a molecular compound, does not have lattice energy in the context of ionic compounds, which makes it irrelevant to the question.

Q126. Which statement applies to both ideal and real gases

• A. Collision between molecules are elastic
• B. Molecules are in constant random motion✓
• C. Molecules attract each other
• D. Molecules have zero size

Explanation: The correct answer is Option B: Molecules are in constant random motion, which applies to both ideal and real gases. This behavior is a fundamental property of gases, regardless of their idealized or real nature.Option A is incorrect because, while elastic collisions are a characteristic of ideal gases, real gases do not always exhibit this behavior due to intermolecular forces.Option C is incorrect as this statement applies to real gases but not to ideal gases, which are defined by the absence of intermolecular attractions.Option D is also incorrect because ideal gas theory assumes molecules are point particles with no volume, but real molecules have a finite size and volume.

Q127. Reaction of 2-Bromobutane with alcoholic KOH yields:

• A. 2-Butanol
• B. 2-Butene✓
• C. 2-Butyne
• D. 1-Butanol

Explanation: The reaction of 2-Bromobutane with alcoholic KOH is an elimination reaction that predominantly follows an E2 mechanism. In this reaction, KOH acts as a base, abstracting a proton from the β-carbon, leading to the formation of the alkene, 2-Butene, while eliminating HBr. The other options are incorrect because:2-Butanol: This would only form through a substitution reaction, which is not favored in this context.2-Butyne: While it is possible to form alkynes through elimination, this specific reaction does not lead to 2-Butyne as the major product.1-Butanol: Similar to 2-Butanol, this alcohol would result from substitution, not elimination, making it an incorrect choice.Overall, 2-Butene is the major product formed under the conditions described.

Q128. The smallest repeating pattern from which the lattice is built in a crystalline solid is called

• A. Crystallite
• B. Amorphous region
• C. Unit cell✓
• D. Crystal lattice

Explanation: The correct answer is Unit cell, as it is defined as the smallest repeating pattern from which the entire lattice structure of a crystalline solid is constructed. Each unit cell represents the entire symmetry and arrangement of the atoms or molecules within the crystal. Crystallite refers to a small, ordered region within a material, but it is not the fundamental repeating unit. Amorphous region indicates an area without a defined structure, which contradicts the concept of a repeating pattern. Crystal lattice describes the overall structure formed by many unit cells, but it is not the smallest repeating unit itself.

Q129. Keeping temperature constant, if pressure is increased, density of gas will

• A. Increases✓
• B. Decreases
• C. Gets doubled
• D. Remains same

Explanation: According to the ideal gas law, which states that PV = nRT, if temperature (T) is held constant and pressure (P) is increased, the volume (V) must decrease. Since density (ρ) is defined as mass (m) divided by volume (V), an increase in pressure results in a decrease in volume, thereby increasing density. Therefore, the correct answer is that the density of the gas will increase. Options B, C, and D are incorrect because: Option B: Density does not decrease with increased pressure at constant temperature.Option C: There is no fixed ratio or doubling effect applicable in this case.Option D: Density will not remain the same, as pressure changes will affect the gas volume.

Q130. Orientation of molecule is more important in following cases except:

• A. High Pressure
• B. Complex molecules
• C. Polyatomic molecules
• D. Low pressure✓

Explanation: The correct answer is Low pressure (Option D) because, under low pressure conditions, the molecules are farther apart, leading to fewer collisions and interactions. As a result, the orientation of molecules has less impact on the reaction outcomes compared to conditions of high pressure, where increased molecular interactions make orientation more critical. High Pressure (Option A), Complex molecules (Option B), and Polyatomic molecules (Option C) all involve scenarios where molecular orientation plays a significant role in determining reaction pathways and efficiencies, thus making them incorrect choices.

Q131. IUPAC name of chloroform is:

• A. Methylchloride
• B. Methyltrichloride
• C. Trichloromethane✓
• D. Chloromethane

Explanation: The correct IUPAC name for chloroform is trichloromethane, which indicates that the compound has three chlorine atoms bonded to a single carbon atom in the methane structure. The other options are incorrect because:Methylchloride refers to chloromethane, which only contains one chlorine atom.Methyltrichloride is not a recognized IUPAC name and incorrectly combines terminology.Chloromethane is another name for methyl chloride, which, like methylchloride, has only one chlorine atom and does not describe chloroform accurately.Thus, trichloromethane is the only name that accurately represents the chemical structure of chloroform.

Q132. Which among the following will react with ammonical cuprous chloride:

• A. 1-butene
• B. 1-butyne✓
• C. 2-butene
• D. 2-butyne

Explanation: Ammonical cuprous chloride is known to react with terminal alkynes to form a complex through nucleophilic attack. Among the options, 1-butyne is the only terminal alkyne that can react with this reagent, while the other options are either alkenes (1-butene and 2-butene) or an internal alkyne (2-butyne), which do not exhibit the same reactivity. Therefore, 1-butyne is the correct answer.

Q133. Which of the following is not a crystalline solid?

• A. KCl
• B. Fe metal
• C. Glass✓
• D. Rhombic S

Explanation: The correct answer is Glass, as it is an amorphous solid and does not exhibit the ordered structure characteristic of crystalline solids. In contrast, KCl, Fe, and Rhombic S are all examples of crystalline solids. KCl forms a lattice structure of ions, Fe has a regular arrangement of atoms in its metallic structure, and Rhombic S has a defined crystalline form. Thus, the other options are not correct as they all exhibit the properties of crystalline solids.

Q134. Which of the following structural change in water molecule leads to the low density of ice?

• A. Formation of ionic bonds
• B. Expansion due to hydrogen bonding✓
• C. Increased kinetic energy
• D. Loss of polarity in molecules

Explanation: When water freezes, the molecules form a crystalline structure maintained by hydrogen bonds, which causes them to be arranged further apart compared to when they are in liquid form. This expansion results in ice having a lower density than liquid water, allowing ice to float. The incorrect options do not accurately describe the behavior of water molecules during freezing: ionic bonds do not play a role, increased kinetic energy is associated with the liquid state, and the polarity of water molecules remains intact and is crucial for hydrogen bonding.

Q135. Which of the following reaction will move backward by decreasing pressure?

• A. A ⇌ T + S✓
• B. 2A ⇌ 3C
• C. K ⇌ L
• D. H + 2M ⇌ 2B + 2D

Explanation: The correct answer is A ⇌ T + S. According to Le Chatelier's principle, when pressure is decreased, the equilibrium will shift towards the side with fewer moles of gas. In this case, the left side has only 1 mole (A), while the right side has 2 moles (T + S). Therefore, decreasing the pressure will cause the reaction to shift backward to the left.For option B (2A ⇌ 3C), the reaction would shift to the right (forward) because the right side has more moles (3) than the left (2). In option C (K ⇌ L), we cannot determine the effect of pressure without knowing the number of moles on each side. Finally, in option D (H + 2M ⇌ 2B + 2D), there are 3 moles on the left and 4 on the right, so a decrease in pressure would also favor the forward reaction.

Q136. If voltage across a resistor is doubled then its resistance will become: (temperature and physical state of the conductor remains constant).

• A. Doubled
• B. Half
• C. Four Times
• D. Remains Constant✓

Explanation: The correct answer is that the resistance remains constant. According to Ohm's Law, defined as V = I * R (where V is voltage, I is current, and R is resistance), the resistance (R) is a characteristic of the material and does not change with the voltage applied, as long as temperature and physical conditions are stable. The other options incorrectly suggest that resistance is affected by changes in voltage. For example, doubling the voltage does not imply a doubling of resistance, nor does it imply any other changes in resistance. Thus, the resistance remains the same.

Q137. A particle is moving in a uniform circular path whoseprojection is executing simple harmonic motion on horizontal diameter. The ratio of instantaneous velocity to the maximum velocity of the projection while passing through the center is:964

• A. 1:1✓
• B. 1:2
• C. 2:1
• D. 1:4

Explanation: In the context of a particle moving in a uniform circular path, the maximum velocity is reached at the center of the motion. At this point, the instantaneous velocity is equal to the maximum velocity, leading to a ratio of 1:1. Other options suggest incorrect relationships, as they imply that the instantaneous velocity is either less than or greater than the maximum velocity at the center, which contradicts the principles of uniform circular motion and simple harmonic motion.

Q138. The option that shows the conditions used by Laplace for connecting the velocity of sound is options medium used thermodynamics process1 solid adiabatic 2 liquids isobaric 3 gas adiabatic 4 gas isothermal

• A. 1 solid adiabatic
• B. 2 liquids isobaric
• C. 3 gas adiabatic✓
• D. 4 gas isothermal

Explanation: The correct answer is option 3: gas adiabatic. Laplace's conditions for the velocity of sound specifically apply to gases when they undergo adiabatic processes, meaning no heat is exchanged with the environment during the sound propagation. In contrast, option 1 refers to solids, which are not the focus of Laplace's conditions, and option 2 mentions liquids under isobaric conditions, which also do not align with Laplace's primary work. Option 4, while relevant to gas behavior, pertains to isothermal conditions rather than the adiabatic ones that Laplace described.

Q139. If different colored light beams have same total energy, which color beam will contain the smallest number of photons?

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

Explanation: In this question, we are asked to determine which color of light beam, given the same total energy, would consist of the smallest number of photons. Since the energy of a photon is inversely proportional to its wavelength (E = hc/λ), shorter wavelengths correspond to higher energy. Therefore, violet light, which has the shortest wavelength, will have the highest energy per photon. This means that for a constant total energy, fewer photons are required to make up that energy. Other colors like blue, green, and red have longer wavelengths, resulting in lower energy per photon, thus requiring more photons to equal the same total energy. Hence, the correct answer is violet.

Q140. A patient is injected with a radioactive isotope to trace blood flow and detect circulation issues. The isotope used is more likely to be:

• A. Iodine-131
• B. Phosphorus-32
• C. Cobalt-60
• D. Sodium-24✓

Explanation: The correct answer is Sodium-24, as it is commonly used in medical imaging to trace blood flow and detect circulation issues. Its emission of gamma rays allows for effective imaging. In contrast, Iodine-131, while useful in thyroid diagnostics, does not serve the purpose of tracing blood flow. Phosphorus-32 is primarily used for treating blood disorders rather than for imaging, and Cobalt-60 is mainly associated with cancer treatment. Therefore, Sodium-24 is the most appropriate choice for the scenario described.

Q141. Water flows through a pipe of 0.02 m2 with a speed of 3 m/s. The pipe narrows to 0.01 m2. The speed in narrower section is:

• A. 1.5 m/s
• B. 3 m/s
• C. 6 m/s✓
• D. 9 m/s

Explanation: To solve this problem, we can apply the principle of continuity, which states that the product of the cross-sectional area (A) and the velocity (v) of a fluid must remain constant along a streamline. This can be expressed mathematically as A1v1 = A2v2. In this case, we have:A1 = 0.02 m2, v1 = 3 m/s, A2 = 0.01 m2We need to find v2. Plugging the values into the equation:0.02 m2 * 3 m/s = 0.01 m2 * v2This simplifies to:0.06 = 0.01 * v2Solving for v2 gives us v2 = 6 m/s. Therefore, the correct answer is option C.Options A, B, and D are incorrect because they do not adhere to the principle of continuity in fluid dynamics.

Q142. In the human circulatory system, turbulent blood flow is mostlikely to occur when the:

• A. Vessel diameter is very small
• B. Velocity of blood is very low
• C. Blood flows through a clogged vessel✓
• D. Blood viscosity increases

Explanation: Turbulent blood flow occurs when the flow of blood becomes chaotic and irregular, which is often the result of obstructions or changes in velocity. In this case, when blood flows through a clogged vessel, the obstruction disrupts the regular flow pattern, increasing turbulence. The other options describe conditions that either promote laminar flow or are less conducive to turbulence. Specifically, small vessel diameter and low blood velocity both favor laminar flow, while increased blood viscosity also tends to stabilize the flow, reducing turbulence.

Q143. A conducting ring is placed near a current-carrying coil. As the current in the coil increases, the induced current in the ringflows:

• A. In the direction of magnetic field
• B. To increases the magnetic flux
• C. To oppose increasing magnetic flux✓
• D. Randomly without a definite direction

Explanation: The correct answer is C: 'To oppose increasing magnetic flux'. According to Lenz's Law, when the current in a coil increases, the magnetic field it produces increases, leading to a change in magnetic flux through the conducting ring placed nearby. The induced current in the ring will flow in a direction that creates a magnetic field opposing this increase, thereby attempting to decrease the overall magnetic flux through the ring.Option A is incorrect as it suggests the induced current flows in the same direction as the magnetic field, which contradicts Lenz's Law. Option B is misleading since the induced current does not flow to increase magnetic flux but rather to oppose its increase. Option D is incorrect because induced currents have a definite direction based on the principles of electromagnetic induction.

Q144. In progressive waves, energy is transferred from one point toanother through:

• A. Circular motion of particles
• B. Oscillatory motion of particles✓
• C. Rotation of particles
• D. Translation of particles

Explanation: In progressive waves, energy is transmitted through oscillatory motion of particles, which means that the particles move back and forth around an equilibrium position without permanently displacing from their original location. This oscillation allows the energy to travel through the medium, enabling the wave itself to propagate. Option A (Circular motion of particles) is incorrect because it does not describe the energy transfer mechanism in progressive waves. Option C (Rotation of particles) is also incorrect, as rotation does not facilitate energy transfer in wave motion. Option D (Translation of particles) is misleading, as it suggests a straight-line movement instead of the necessary oscillatory behavior required for energy transfer in progressive waves.

Q145. A capacitor is connected to an ac source. If theffrequency of fthe AC source is doubled the current in a purely capacitive circuit will

• A. Be doubled✓
• B. Remains Unchanged
• C. Become Half
• D. Becomes zero

Explanation: In a purely capacitive circuit, the relationship between current (I) and frequency (f) can be described by the formula I = V * ω * C, where V is the voltage, ω (angular frequency) is related to the frequency by the equation ω = 2πf, and C is the capacitance. When the frequency of the AC source is doubled, the angular frequency (ω) also doubles, directly leading to a doubling of the current (I). Therefore, the correct answer is that the current will be doubled.Other options are incorrect because:Remains Unchanged: This is incorrect because increasing frequency affects current directly.Become Half: This is incorrect as it contradicts the direct proportionality of current to frequency.Becomes zero: This is also incorrect since doubling frequency does not lead to a cessation of current.

Q146. When thermal energy is transferred from a hot object to acold one, the change occurs in the hot object as

• A. Increases in internal energy
• B. Decrease in internal energy✓
• C. Increase in temperature
• D. Increase in heat content

Explanation: The correct answer is Option B: Decrease in internal energy. When thermal energy is transferred from a hot object to a cold one, the hot object loses thermal energy, which results in a decrease in its internal energy. This is consistent with the second law of thermodynamics, which states that heat flows from a hotter object to a cooler one until thermal equilibrium is reached.Option A is incorrect because it suggests that the hot object gains internal energy, which contradicts the heat transfer process. Option C is also incorrect, as the temperature of the hot object actually decreases during this process, not increases. Lastly, Option D is misleading; the hot object does not increase its heat content, but rather decreases it as it loses energy to the cold object.

Q147. The electric potential at a point due to a point charge is 100J/C. If a test charge of magnitude 1C placed at that point is replaced with a 2C charge, then the physical quantity that will change is

• A. Electric Field at that point
• B. Electric potential at that point✓
• C. Electric Potential Energy of the system
• D. Temperature

Explanation: The correct answer is Electric potential at that point. The electric potential at a specific point in space due to a point charge is defined as the work done per unit charge in bringing a small positive test charge from infinity to that point. In this case, even though the test charge is replaced from 1C to 2C, the potential due to the source charge remains constant. Therefore, the electric potential itself does not change.On the other hand, the Electric Field at that point does not change as it is a property of the source charge. The Electric Potential Energy of the system will change because it is calculated as the product of the electric potential and the charge, which will increase when the 1C charge is replaced with a 2C charge. Finally, Temperature is unrelated to the electrical properties being discussed and thus remains unchanged.

Q148. When two identical waves arrive in phase at same poin a region at the same time the resultant displacement isequal to

• A. Displacement of a single wave
• B. Difference of their displacements
• C. Sum of their displacements✓
• D. Product of their displacements

Explanation: When two identical waves arrive in phase at the same point, their displacements combine through the principle of superposition. This means that instead of remaining equal to just one wave's displacement (Option A), or being the difference (Option B) or the product (Option D) of their displacements, the correct resultant displacement is the sum of their displacements (Option C). This results in a wave with greater amplitude, demonstrating how constructive interference works in wave mechanics.

Q149. Two spectral lines in the Hydrogen atom spectrum are close together. This likely means:

• A. The energy difference is zero
• B. The energy difference is small✓
• C. The light intensity is low
• D. The atom becomes unstable

Explanation: In the Hydrogen atom spectrum, spectral lines represent transitions between different energy levels. When two spectral lines are close together, it indicates that the energy difference between the two levels involved in these transitions is small. This is because the energy levels are quantized and can be very close for certain transitions, especially in hydrogen where the energy levels converge at higher levels. Therefore, option B is correct. Option A is incorrect because a zero energy difference would mean the lines overlap instead of being distinct. Option C incorrectly associates light intensity with line spacing, and option D is misleading as the mere presence of closely spaced lines does not imply instability in the atom.

Q150. What will potential difference, if a wire has resistance of 10 ohms and current 2A flow through it:

• A. 5V
• B. 10V
• C. 20V✓
• D. 40V

Explanation: To find the potential difference across a wire, we can use Ohm's law, which states that Voltage (V) equals Current (I) multiplied by Resistance (R). For this question, we have:Resistance (R) = 10 ohms and Current (I) = 2A.Applying Ohm's Law: V = I × R = 2A × 10Ω = 20V.Therefore, the correct answer is 20V (Option C). The other options are incorrect because:5V and 10V do not correspond to the correct calculations based on the given resistance and current.40V suggests a higher current than is provided, making it impossible under the given conditions.

Q151. According to the particle model of light, a photon is:

• A. A Particle with mass and charge
• B. A quantum of energy with zero rest mass and zero charge✓
• C. A continuous energy wave
• D. A particle that travels slower than light

Explanation: The correct answer is that a photon is a quantum of energy with zero rest mass and zero charge. This is supported by the principles of quantum mechanics, which state that photons exhibit both particle-like and wave-like behavior. Importantly, photons are massless, allowing them to travel at the speed of light, which is approximately 299,792 kilometers per second in a vacuum.Option A is incorrect because it incorrectly attributes mass and charge to photons, which they do not possess. Option C, while touching on the wave nature of light, fails to recognize that photons are discrete packets of energy rather than a continuous wave. Finally, Option D is incorrect since it states that a photon travels slower than light, which contradicts the fundamental properties of light as described in physics.

Q152. The current in forward biased PN junction is mainly due to:

• A. Majority carriers✓
• B. Minority carriers
• C. leakage carrier
• D. Thermionic emission

Explanation: In a forward-biased PN junction, the external voltage reduces the potential barrier, allowing majority carriers (electrons in n-type and holes in p-type) to move across the junction, resulting in a flow of current. This is why option A, which refers to majority carriers, is correct. Option B (minority carriers) is incorrect, as they contribute little to the current in this condition. Option C (leakage carrier) is not a standard term in semiconductor discussions, thus it does not apply here. Option D (thermionic emission) is also incorrect as it describes a different phenomenon related to electron emission from heated surfaces, not the current flow in a PN junction.

Q153. Stationary waves are formed in a stretched string of 2m length, such that two vibrating loops are formed. The distance between consecutive nodes formed is:

• A. 0.5 m
• B. 1 m✓
• C. 2 m
• D. 3 m

Explanation: In a stretched string of length 2m, if two vibrating loops are formed, it indicates that there are two antinodes (the points of maximum amplitude) and three nodes (the points of zero amplitude). The distance between consecutive nodes is half the distance of the string divided by the number of loops formed. Thus, the total distance of 2m divided by the two loops results in a distance between nodes of 1m. The other options (0.5m, 2m, and 3m) do not align with the calculation based on the wave properties described.

Q154. A football is kicked with a speed of 20 m/s at an angle of 30° With the horizontal, the maximum height it attains is:

• A. 5 m✓
• B. 10 m
• C. 15 m
• D. 20 m

Explanation: The correct maximum height can be calculated using the formula: H = (vy2)/(2g), where vy is the vertical component of the initial velocity and g is the acceleration due to gravity (approximately 9.81 m/s2). First, we need to find the vertical component:vy = v * sin(θ) = 20 m/s * sin(30°) = 20 m/s * 0.5 = 10 m/sNow, substituting this value into the height formula:H = (10 m/s)2 / (2 * 9.81 m/s2) ≈ 5.1 mRounding down, we find the maximum height is approximately 5 m.Thus, Option A (5 m) is correct. Options B, C, and D are incorrect as they do not reflect the correct calculations based on the initial vertical velocity derived from the given speed and angle.

Q155. A high internal resistance battery is not suitable for heavy loads due to:

• A. Excess voltage drop✓
• B. High terminal voltage
• C. Infinite emf
• D. Constant current

Explanation: The correct answer is 'Excess voltage drop.' A battery with high internal resistance will experience a substantial voltage drop across its internal components when a heavy load is applied. This results in a lower voltage output to the load, which can impair its efficiency and effectiveness in powering devices. The other options are incorrect because high terminal voltage does not imply the battery can handle heavy loads, infinite emf is a theoretical notion that does not exist in practical applications, and constant current is not achievable under high internal resistance conditions.

Q156. Two equal charges experience a certain force when placed in vacuum. When the charges are placed in a medium, the force becomes 1/4 th. The dielectric constant of the medium is:

• A. 0.25
• B. 2
• C. 4✓
• D. 16

Explanation: When two equal charges are placed in a vacuum, they experience a certain force. According to Coulomb's law, the force (F) between two charges (q1 and q2) is given by the formula: F = k * (q1 * q2) / r^2, where k is the electrostatic constant. When the charges are placed in a medium with a dielectric constant (k'), the force becomes F' = F / k'. Given that the new force is 1/4th of the original (F' = F/4), we can set up the equation: F / k' = F / 4. This simplifies to k' = 4, indicating that the dielectric constant of the medium is 4. Hence, Option C is correct. The other options do not satisfy the condition of the force being reduced to 1/4th.

Q157. If a test charge of magnitude 2C experience forces of 100N 1 and 200N at two points A and B in an electric field respectively. The ratio of electric fields at A to that of B is

• A. 1:1
• B. 1:2✓
• C. 1:4
• D. 4:1

Explanation: To find the ratio of the electric fields at points A and B, we use the relationship E = F/q. For point A, the electric field E_A can be calculated as E_A = 100N / 2C = 50 N/C. For point B, E_B = 200N / 2C = 100 N/C. The ratio of the electric fields at A to B is E_A : E_B = 50 N/C : 100 N/C = 1:2. Therefore, the correct answer is Option B (1:2). The other options are incorrect because they do not accurately reflect the calculated ratio based on the forces experienced by the test charge.

Q158. A body of mass 2 kg moving with velocity 3 m/s collides with a body of mass 1 kg at rest. If they stick together, their common velocity after collision is

• A. 1 m/s
• B. 2 m/s✓
• C. 3 m/s
• D. 4 m/s

Explanation: To find the common velocity after the collision of two bodies that stick together, we use the principle of conservation of momentum. The total momentum before the collision equals the total momentum after the collision. The initial momentum is calculated as follows: for the first body (mass = 2 kg, velocity = 3 m/s), the momentum is 2 kg * 3 m/s = 6 kg·m/s. The second body is at rest, contributing 0 kg·m/s. Therefore, the total initial momentum is 6 kg·m/s. After the collision, the two bodies stick together, so the total mass is 2 kg + 1 kg = 3 kg. Letting v be their common velocity, we set up the equation: 6 kg·m/s = 3 kg * v. Solving for v, we find v = 2 m/s. Thus, the correct answer is 2 m/s. Options 1 m/s, 3 m/s, and 4 m/s do not satisfy the conservation of momentum principle, making them incorrect.

Q159. Two balls thrown with equal speeds but at different angles cover equal horizontal distance. If one is thrown at an angle of 40°, then the angle of projection of the other is:

• A. 20°
• B. 30°
• C. 45°
• D. 50°✓

Explanation: When two projectiles are thrown with the same initial speed and cover the same horizontal distance, their angles of projection are complementary angles. Since one ball is thrown at an angle of 40°, the other must be thrown at an angle of 90° - 40° = 50° to achieve the same horizontal range. Therefore, the correct answer is 50°. The other options do not meet the criteria of being complementary to 40° and will not result in the same horizontal distance.

Q160. The work done on a body is stored in it in the form of:

• A. Power
• B. Energy✓
• C. Momentum
• D. Impulse

Explanation: The work done on a body is converted into energy and stored within that body. Energy is a scalar quantity that represents the capacity for doing work, which is why option B is correct. In contrast, power (option A) relates to the rate of doing work, not the work itself; momentum (option C) describes motion rather than energy storage; and impulse (option D) refers to changes in momentum, which do not directly relate to stored work. Thus, the only viable answer is energy.

Q161. If 20 waves pass a point in 2 seconds and with a speed of 5m/s, then the wavelength of wave is:

• A. 0.5 m✓
• B. 1 m
• C. 1.5 m
• D. 2 m

Explanation: To find the wavelength of the wave, we first calculate the frequency. Given that 20 waves pass a point in 2 seconds, the frequency (f) is calculated as: f = number of waves / time = 20 waves / 2 seconds = 10 Hz. Next, we use the wave speed (v) of 5 m/s in the formula for wavelength (λ): λ = v / f. Substituting the values gives us λ = 5 m/s / 10 Hz = 0.5 m. Therefore, the correct answer is option A (0.5 m). Options B (1 m), C (1.5 m), and D (2 m) are incorrect because they do not align with the calculated frequency and wave speed.

Q162. The unit of RC in case of charging a capacitor is

• A. Farad
• B. Seconds✓
• C. Ohm
• D. Volt

Explanation: The correct answer is Seconds, as the RC time constant (τ) is defined as the time it takes for a capacitor to charge to approximately 63.2% of its maximum voltage. It is calculated as τ = R × C, where R is the resistance in ohms and C is the capacitance in farads. Since the product of resistance and capacitance results in a time measurement, the unit for RC is seconds. The other options are incorrect because Farads measure capacitance, Ohms measure resistance, and Volts measure electric potential, none of which directly indicate the time it takes for a capacitor to charge.

Q163. A longitudinal wave has a frequency of 500 Hz and wavelength of 0.6 m, its speed is:

• A. 30 m/s
• B. 83 m/s
• C. 300 m/s✓
• D. 1200 m/s

Explanation: To calculate the speed of a longitudinal wave, you multiply its frequency by its wavelength. In this case, the frequency is 500 Hz and the wavelength is 0.6 m. Thus, the speed is calculated as follows: speed = frequency × wavelength = 500 Hz × 0.6 m = 300 m/s. Therefore, Option C is correct. Options A, B, and D are incorrect because they do not result from the proper application of the formula.

Q164. The true statement about angular displacement is:

• A. It always increases with time
• B. It is treated as vector for small rotations✓
• C. It is always a scalar quantity
• D. It is measured in meters

Explanation: The correct answer is Option B: 'It is treated as vector for small rotations.' This is accurate because angular displacement, which indicates the angle of rotation about an axis, is indeed a vector quantity, encompassing both direction and magnitude. In contrast, Option A is incorrect because angular displacement can decrease or remain constant depending on the rotation direction. Option C is misleading since angular displacement is not a scalar; it is fundamentally a vector. Finally, Option D is incorrect as angular displacement is measured in radians, not in meters, which are units of linear distance.

Q165. π radians are equivalent to

• A. 30°
• B. 270°
• C. 90°
• D. 180°✓

Explanation: The correct answer is 180°, which is equivalent to π radians. In the conversion from radians to degrees, the formula used is: Degrees = Radians × (180/π). Thus, π radians equals π × (180/π) = 180°. The other options are incorrect as they represent different angles in degrees: 30° corresponds to π/6 radians, 90° corresponds to π/2 radians, and 270° corresponds to 3π/2 radians.

Q166. The waves among the following which require a materialmedium for their propagation are:

• A. Gamma rays
• B. X-rays
• C. Infrared waves
• D. Infrasonic waves✓

Explanation: The correct answer is Infrasonic waves (Option D), as they are sound waves that require a material medium for their propagation. Unlike electromagnetic waves such as gamma rays, X-rays, and infrared waves, which can travel through a vacuum, infrasonic waves depend on a material environment to transmit their energy. This makes them distinct in the types of waves mentioned.Options A, B, and C (gamma rays, X-rays, and infrared waves) are all electromagnetic waves that can travel through the vacuum of space without the need for a material medium, which is why they are incorrect answers.

Q167. Unequal-changes occurring in velocity of a body is called

• A. Uniform acceleration
• B. Uniform velocity
• C. Instantaneous acceleration
• D. Variable acceleration✓

Explanation: The correct answer is Variable acceleration because it specifically describes a situation where a body's acceleration is not constant, leading to unequal changes in velocity. In contrast, Uniform acceleration implies a steady rate of change in velocity, which contradicts the question's condition of unequal changes. Uniform velocity indicates no change in velocity at all, and Instantaneous acceleration only refers to a specific moment rather than ongoing changes. Thus, only Variable acceleration accurately captures the essence of the question.

Q168. A person moves 600 m towards north then 300 m towards south. Its displacement to distance ratio is:

• A. 1:2
• B. 1:3✓
• C. 2:1
• D. 3:1

Explanation: To find the displacement to distance ratio, we first calculate the total distance traveled and the net displacement. The person moves 600 m north and then 300 m south. The total distance traveled is 600 m + 300 m = 900 m. The displacement, or the shortest distance from the starting point to the final position, is the difference between the northward and southward movements: 600 m (north) - 300 m (south) = 300 m (net north). Therefore, the displacement to distance ratio is 300 m (displacement) to 900 m (distance), which simplifies to 1:3. The other options are incorrect because they do not accurately reflect the relationship between the calculated displacement and total distance.

Q169. In a stationary wave the point that undergoes zero acceleration is:

• A. Node✓
• B. Antinode
• C. Midpoint between node and antinode
• D. Every point along the wave

Explanation: The correct answer is Node, as nodes are specific points in a stationary wave where the medium does not move, resulting in zero acceleration. In contrast, antinodes represent points of maximum displacement and maximum velocity in the wave, thus having the highest acceleration. The midpoint between a node and an antinode does not qualify as a node since it does not have zero displacement, and stating that every point along the wave experiences zero acceleration is inaccurate since only nodes do.

Q170. If the speed of sound is measured at sea level and at the top of a mountain, both at the same temperature. It will be:

• A. Greater at sea level
• B. Greater at the mountain top
• C. The same at both places
• D. Greater where the air is denser✓

Explanation: The speed of sound is influenced by the density of the medium through which it travels. At sea level, the air is denser than at the top of a mountain. Therefore, under the same temperature conditions, sound will travel faster at sea level where the air is denser. Option A is incorrect because it misinterprets the relationship between density and sound speed. Option B suggests that sound is faster at the mountain top, which contradicts the principles of sound propagation. Option C incorrectly claims that the speed is the same at both locations, overlooking the impact of air density. Thus, the correct answer is Option D, as sound travels faster in denser air.

Q171. High slope of Ohm's law graph means:

• A. Low resistance
• B. High resistance✓
• C. Open circuit
• D. Low current

Explanation: The correct answer is Option B: High resistance. According to Ohm's law (V = IR), where V is voltage, I is current, and R is resistance, the slope of the voltage-current graph (V vs. I) represents the resistance (R). A steeper slope indicates a higher resistance, meaning that less current flows for a given voltage. Therefore, when the slope is high, it signifies that the resistance is also high. Option A is incorrect because a low slope corresponds to low resistance, which would allow for higher current. Option C is incorrect as an open circuit results in no current flow, and thus cannot be represented by a high slope. Option D is misleading because while high resistance can lead to low current, the direct interpretation of a high slope in the graph specifically indicates high resistance.

Q172. An outbreak of a corona disease is reported in the city. What should be the first course of action?

• A. Develop a vaccination plan.
• B. Conduct research on the disease.
• C. Implement quarantine measures.✓
• D. Inform the public by using all means.

Explanation: The correct answer is to implement quarantine measures, as this is the most effective first step in controlling the spread of a contagious disease during an outbreak. Quarantine helps isolate individuals who may be infected and prevents further transmission. Developing a vaccination plan or conducting research may be important later, but they do not provide immediate action to address the outbreak. Informing the public is essential for awareness and compliance, but it must coincide with direct actions such as quarantine to be effective.

Q173. Find the next number: 5,11,23,47,95,_?

• A. 190
• B. 191✓
• C. 192
• D. 193

Explanation: The sequence provided is 5, 11, 23, 47, 95. To find the next number, we can analyze the differences between each pair of consecutive numbers: 11 - 5 = 623 - 11 = 1247 - 23 = 2495 - 47 = 48We observe that each difference is doubling: 6, 12, 24, 48. Following this pattern, the next difference should be 48 * 2 = 96. Thus, we add 96 to the last number in the sequence:95 + 96 = 191.Therefore, the next number is 191. The other options are incorrect because they do not follow the identified pattern of doubling differences.

Q174. Which number comes in the missing place? 1,3,7, 15, 31,.

• A. 61
• B. 63✓
• C. 65
• D. 67

Explanation: To find the next number in the sequence (1, 3, 7, 15, 31), observe the pattern: each number is generated by doubling the previous number and adding 1. For example: 1 × 2 + 1 = 3; 3 × 2 + 1 = 7; 7 × 2 + 1 = 15; 15 × 2 + 1 = 31. Following this pattern, the next number should be 31 × 2 + 1 = 63. Options 61, 65, and 67 do not follow this consistent doubling rule, hence they are incorrect.

Q175. Every alphabet in the word "SURGEON" represent a fixed numerical value and the numbers when added, sum up to 99. Based on this, what will the sum of the word "EORGNSU".

• A. 102
• B. 78
• C. 99✓
• D. 56

Explanation: The letters in the word 'SURGEON' collectively have a fixed numerical value that sums to 99. Since the question asks for the sum of the rearranged word 'EORGNSU', and because the numerical values assigned to each letter do not change regardless of their order, the sum remains 99. Therefore, option C is correct. Options A, B, and D are incorrect because they either exceed or fall short of the total sum of 99, indicating a misunderstanding of the numerical values assigned to the letters.

Q176. What is the primary difference between hypothesis and a theory?

• A. A hypothesis is a proven fact, while a theory is an unproven data.
• B. A hypothesis is a specific prediction, while a theory is a broad explanation.
• C. A hypothesis is a qualitative statement, while a theory is quantitative statement.
• D. A hypothesis is a tentative explanation, while a theory is a well-established explanation.✓

Explanation: A hypothesis is a proposed explanation made on the basis of limited evidence as a starting point for further investigation; it is often a specific prediction that can be tested through experiments. In contrast, a theory is a well-substantiated explanation acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation. Therefore, the correct answer is that a hypothesis is a tentative explanation, while a theory is a well-established explanation. The other options misrepresent the definitions of hypothesis and theory, either by stating incorrect relationships or by oversimplifying their nature.

Q177. ZX, WU, TR, QO.. What comes next?

• A. NL✓
• B. LN
• C. NM
• D. KH

Explanation: The sequence is formed by taking pairs of letters where the first letter decreases and the second letter increases with each step. Starting from ZX, the first letter decreases by 2 (Z to X) and the second letter increases by 2 (X to W). Following this pattern, the next pair should be NL, where N is two letters before P and L is two letters after J. Other options do not match this established pattern.

Q178. In a row of students, a student is at 13th position from the left end and at 20th position from the right end. How many students are there in the row?

• A. 30
• B. 31
• C. 32✓
• D. 33

Explanation: The total number of students can be calculated using the formula: Total Students = Position from Left + Position from Right - 1. In this case, the student is at the 13th position from the left end and the 20th position from the right end. Therefore, the calculation is: Total Students = 13 + 20 - 1 = 32. Option A (30) is incorrect because it does not consider the overlap. Option B (31) is incorrect for the same reason. Option D (33) counts one additional student erroneously. Thus, the correct answer is Option C (32).

Q179. A is older than B but younger than F. C is younger than B but older than D. Who is the youngest of them?

• A. A
• B. B
• C. C
• D. D✓

Explanation: To solve the problem, we establish the age relationships:A is older than B but younger than F. This gives us the order: B < A < F.C is younger than B but older than D, leading to the order: D < C < B.Combining these two sequences, we get: D < C < B < A < F. From this, we can see that D is the youngest of them all.Therefore:A is eliminated because he is older than B.B is eliminated because he is older than C.C is eliminated because he is older than D.This confirms that D is the youngest of the group.

Q180. A hiker climbed to a higher altitude, where he felt the air pressure was lower as compared to the lower altitude. What is the likely effect?

• A. The hiker felt more energetic.
• B. The hiker felt no difficulty in breathing.
• C. The hiker might experience altitude sickness.✓
• D. The hiker felt healthier and fresh.

Explanation: The correct answer is that the hiker might experience altitude sickness. This condition arises when the body struggles to adapt to lower oxygen levels at high altitudes, leading to symptoms like headache, nausea, and fatigue. The other options are incorrect because they either suggest an increase in energy or well-being, which is not typical as the body requires time to acclimatize to changes in air pressure. Difficulty in breathing is common at higher altitudes due to the reduced availability of oxygen.