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Uhs Mdcat 2015 — Solved Past Paper with Answers
All 219 MCQs from Uhs Mdcat 2015, solved with the correct answer highlighted and a full explanation for every question. This is a free MDCAT Punjab / UHS past paper — no signup, no ads. Practise it interactively in timed mode, drill more with free MDCAT MCQs, or browse all Punjab / UHS papers.
Attempt this paper interactively →Q1. In spite of all the torture, the police have failed to _ any confession from the thief.
- A. Convince
- B. Elicit✓
- C. Refuse
- D. Refuse
Explanation: The correct option in this case is (b) elicit, as it aligns with the context of the sentence and implies that the police have been unsuccessful in obtaining a confession from the thief despite using torture. This option indicates that the police have been unsuccessful in obtaining or extracting a confession from the thief. It suggests that the police have tried various methods or techniques to get the thief to confess, but none of them have worked.
Why the other options are wrong
- A. This option suggests that the police have been unable to persuade or make the thief confess despite their efforts or methods of persuasion. It implies that the police have been trying to change the thief's mind or convince them to admit their guilt, but they have not been successful.
- C. This option is contradictory to the context. "Refuse" means to decline or reject something, so it does not fit the sentence. The police would not be refusing a confession; they would be attempting to obtain one.
- D. This option is contradictory to the context. "Refuse" means to decline or reject something, so it does not fit the sentence. The police would not be refusing a confession; they would be attempting to obtain one.
Q2. It is the duty of a teacher to _ moral values in his students besides teaching.
- A. Tell
- B. Record
- C. Inculcate✓
- D. Suggest
Explanation: the correct option in this case is (c) inculcate, as it conveys the idea that it is the duty of a teacher to actively and persistently instill moral values in their students, rather than just telling or suggesting them.
Why the other options are wrong
- A. Incorrect. This option suggests that the duty of a teacher is to verbally communicate or share moral values with their students. It implies that the teacher simply conveys the values without necessarily ensuring they are understood or internalized by the students.
- B. Incorrect. This option does not fit the context of the sentence. "Record" refers to the act of documenting or preserving information, and it does not align with the idea of imparting moral values to students.
- D. This option is not correct in this context. "Suggest" implies offering an idea or proposal, but it doesn't capture the essence of a teacher's duty to impart moral values. The role of a teacher is more active and involved than just suggesting; it entails actively teaching, guiding, and inculcating moral values in students.
Q3. Many of the houses in Murree have basic _.
- A. Amenities✓
- B. Accuracy
- C. Affinity
- D. Array
Explanation: Amenities refer to the facilities or features that contribute to the comfort, convenience, and enjoyment of a place. In the context of houses in Murree, having basic amenities means that these houses are equipped with essential services and facilities that make them comfortable and functional. Therefore, option (A) suggests that the houses in Murree have basic facilities and services
Why the other options are wrong
- B. Accuracy refers to the degree of correctness, precision, or exactness in something. In the given context of houses in Murree, the term accuracy does not seem to fit. Accuracy is more commonly associated with measurements, calculations, or data rather than describing the characteristics of houses. Therefore, option (B) is not the most suitable term to complete the sentence.
- C. Affinity generally refers to a natural liking, attraction, or connection towards something or someone. In the context of houses in Murree, the term affinity does not convey a clear meaning. It does not provide a relevant description of the houses. Therefore, option (C) is not the most appropriate term for completing the sentence.
- D. An array typically refers to an ordered arrangement or display of things in a particular pattern or order. In the context of houses in Murree, the term array does not provide a clear description. It does not convey the idea of basic characteristics or features of the houses. Therefore, option (D) is not the most suitable term to complete the sentence.
Q4. Youngsters who indulge in love affairs are usually _ in worldly matters.
- A. Adjoined
- B. Addled✓
- C. Adjured
- D. Adhesive
Explanation: The term "addled" refers to being confused, muddled, or mentally disoriented. In the given context, using "addled" suggests that youngsters who indulge in love affairs are usually confused or mentally disoriented when it comes to worldly matters. This implies that their focus or attention may be primarily on their romantic relationships, potentially leading to a lack of understanding or awareness of practical matters. Therefore, option (b) could be a suitable term to complete the sentence.
Why the other options are wrong
- A. The term "adjoined" means to be joined or connected to something physically or in close proximity. In the given context, the term does not fit well. Being adjoined in worldly matters does not convey a clear meaning or provide a suitable description of youngsters who indulge in love affairs. Therefore, option (a) is not the most appropriate term to complete the sentence.
- C. The term "adjured" means to earnestly request, urge, or command someone to do something. In the given context, using "adjured" does not provide a clear or appropriate meaning. It does not convey a relevant description of youngsters who indulge in love affairs and their behavior in worldly matters. Therefore, option (c) is not the most suitable term to complete the sentence.
- D. The term "adhesive" refers to something that sticks or adheres to another object or surface. In the given context, using "adhesive" does not convey a meaningful or suitable description. It does not provide a clear understanding of how youngsters who indulge in love affairs are usually in worldly matters. Therefore, option (d) is not the most appropriate term to complete the sentence.
Q5. Identify the segment in the following sentence which contains the mistake that needs to be corrected. He picked up one or two magazines and after a hurried glance on the contents carefully replaced them.
- A. picked up
- B. a hurried
- C. on✓
- D. replaced
Explanation: The correct phrase would be a glance at the contents. OPTION A: incorrectOPTION B: incorrectOPTION C: correctOPTION D: Incorrect
Why the other options are wrong
- A. The phrase "picked up" in the sentence indicates the action of physically lifting or taking hold of something. Without further context, there doesn't appear to be any grammatical or structural mistake in this segment. However, it's worth noting that it's always important to consider the broader context of the sentence or paragraph to ensure proper usage and correctness.
- B. The phrase "a hurried" precedes the noun "glance" and is used to describe the type of glance taken by the subject. However, the use of the indefinite article "a" before "hurried" seems inappropriate in this context. It would be more accurate and grammatically correct to use the definite article "the" instead, as it indicates a specific hurried glance rather than any random hurried glance.
- D. The verb "replaced" indicates the action of putting something back in its original position or replacing it with something else. Without further context, there doesn't appear to be any grammatical or structural mistake in this segment. However, it's important to consider the overall meaning and intention of the sentence to ensure correctness.
Q6. Identify the segment in the following sentence which contains the mistake that needs to be corrected.His guests found it fun to watch him make tea – mixing carefully spoonful from different caddies
- A. It fun
- B. To watch
- C. Make
- D. Carefully spoonful✓
Explanation: The correct answer is 'Careful spoonful'. The error in the sentence lies in the phrase 'mixing carefully spoonful from different caddies'. It should read as 'careful spoonfuls' to correctly use 'careful' as an adjective modifying 'spoonfuls', or 'carefully spooning' to use 'carefully' as an adverb modifying the action of 'spooning'. The other options do not contain any errors, as they are properly structured in the context of the sentence.
Why the other options are wrong
- A. This segment is grammatically correct. 'Fun' is appropriately used as a noun here.
- B. This segment is correct. The phrase 'to watch' fits well in the context of the sentence.
- C. The verb 'make' is correctly used to describe the action of preparing tea.
Q7. Identify the segment in the following sentence which contains the mistake that needs to be corrected.You have put your life in his hands many a times.
- A. Put your life
- B. In his hands
- C. Many a
- D. Times✓
Explanation: The phrase “many a time” is singular and idiomatic; using “times” is incorrect.
Why the other options are wrong
- A. This segment does not contain the mistake. It accurately describes the action of entrusting or placing one's life in someone else's care.
- B. This segment does not contain the mistake. It correctly indicates the location or responsibility of the person in whom the life is being entrusted.
- C. This segment does not contain the mistake that needs to be corrected.
Q8. Identify the segment in the following sentence which contains the mistake that needs to be corrected.Chips, thinking it over a good many time, always added to himself that Kathie would have approved and also have been amused.
- A. A good many time✓
- B. Added to himself
- C. Would have approved
- D. Have been amused
Explanation: This segment contains the mistake that needs to be corrected. The correct phrase should be "a good many times" instead of "a good many time." The use of "time" instead of "times" is grammatically incorrect when referring to multiple instances.
Why the other options are wrong
- B. This segment does not contain the mistake. It correctly describes the action of mentally adding or thinking about something for oneself.
- C. This segment does not contain the mistake. It accurately describes a hypothetical situation where Kathie would have given her approval.
- D. This segment does not contain the mistake. It correctly describes a hypothetical situation where Kathie would have experienced amusement.
Q9. Identify the segment in the following sentence which contains the mistake that needs to be corrected.But the men ate their supper in good appetites.
- A. Men
- B. Ate
- C. Their
- D. In✓
Explanation: This segment contains the mistake that needs to be corrected. The correct preposition to use in this sentence is "with" instead of "in." The correct phrase should be "ate their supper with good appetites" to indicate that the men had hearty appetites while eating their meal.
Why the other options are wrong
- A. This segment does not contain the mistake. It accurately refers to the group of individuals being discussed in the sentence.
- B. This segment does not contain the mistake. It correctly describes the action of consuming food.
- C. This segment does not contain the mistake. It accurately indicates that the supper belonged to or was associated with the men.
Q10. Identify the segment in the following sentence which contains the mistake that needs to be corrected.A common sense of failure is a mistaken ambition of the boys of the part of his parents.
- A. Common
- B. On
- C. Of✓
- D. His
Explanation: This segment contains the mistake that needs to be corrected. The correct preposition to use in this sentence is "of" instead of "on." The correct phrase should be "on the part of" to indicate the involvement or responsibility of the parents in the mistaken ambition of the boys. OPTION A: incorrectOPTION B: correctOPTION C: incorrectOPTION D: incorrect
Why the other options are wrong
- A. This segment does not contain the mistake. It correctly describes the sense of failure being discussed in the sentence as something that is shared or common.
- B. This segment contains the mistake that needs to be corrected. The correct preposition to use in this sentence is "of" instead of "on." The correct phrase should be "on the part of" to indicate the involvement or responsibility of the parents in the mistaken ambition of the boys.
- D. This segment does not contain the mistake. It correctly indicates the possessive form, suggesting the parents belong to the boys.
Q11. Choose the correct sentence from the following:
- A. Tourism is burgeoned over the last fifteen years.
- B. Tourism will burgeoned over the last fifteen years.
- C. Tourism have burgeoned over the last fifteen years.
- D. Tourism has burgeoned over the last fifteen years.✓
Explanation: "Tourism has burgeoned over the last fifteen years.": This sentence is grammatically correct. It uses the present perfect tense, correctly indicating that tourism has experienced growth or development over the last fifteen years.
Why the other options are wrong
- A. This sentence is grammatically incorrect. The verb "burgeoned" is in the wrong form. The correct form should be "has burgeoned" to indicate an action that happened in the past and continues into the present
- B. This sentence is grammatically incorrect. The verb "burgeoned" is in the wrong form. The correct form should be "has burgeoned" to indicate an action that happened in the past and continues into the present. Additionally, the use of "will" is incorrect because the action is already completed over the last fifteen years.
- C. This sentence is grammatically incorrect. The verb "have burgeoned" is not in agreement with the subject "Tourism." The correct form should be "has burgeoned" to match the singular subject.
Q12. Choose the correct sentence from the following:
- A. His remains were interred in the new cemetery.✓
- B. His remains were entered in the new cemetery.
- C. His remains was interred in the new cemetery.
- D. His remains was entered in the new cemetery.
Explanation: "His remains were interred in the new cemetery.": This sentence is grammatically correct. The verb "interred" is used in the past tense to indicate the burial or placement of the remains in the new cemetery. Additionally, the verb agrees with the subject "remains" in the plural form.
Why the other options are wrong
- B. "His remains were entered in the new cemetery.": This sentence is not the correct option. The verb "entered" is incorrect in this context. "Enter" does not accurately describe the action of burying or placing remains in a cemetery. The correct verb to use in this context is "interred" to convey the meaning of burial.
- C. "His remains was interred in the new cemetery.": This sentence is grammatically incorrect. The subject "remains" is plural, so the verb should also be plural. The correct form should be "were interred" to match the subject.
- D. "His remains was entered in the new cemetery.": This sentence is not the correct option. Similar to option C, the subject "remains" should be followed by a plural verb form. The correct form should be "were entered" to match the plural subject.
Q13. Choose the correct sentence from the following:
- A. The Return of the King which is a popular movie made a huge amount of money
- B. "The Return of the King", which is a popular movie made a huge amount of money.
- C. "The Return of the King", which is a popular movie, made a huge amount of money.✓
- D. "The return of the king", which is a popular, movie, made a huge amount of money.
Explanation: The Return of the King is a title, therefore it must be in between quotation marks. Therefore, Option A is incorrect. Since it is a title, it must also be capitalised. This means that option D is incorrect.Finally, 'which is a popular movie' is a dependent clause. Therefore, it must be contained within commas. This means option B is incorrect. Therefore, option C is the right answer.
Why the other options are wrong
- A. The Return of the King is a title, therefore it must be in between quotation marks. Therefore, Option A is incorrect.
- B. Finally, 'which is a popular movie' is a dependent clause. Therefore, it must be contained within commas. This means option B is incorrect.
- D. Since it is a title, it must also be capitalised. This means that option D is incorrect.
Q14. Choose the correct sentence from the following.
- A. The cheery trees stand over the woodland ride.
- B. The cheery trees stand about the woodland ride.✓
- C. The cheery trees beside about the woodland ride.
- D. The cheery trees stand on the woodland ride.
Explanation: The phrase “stand about” means the trees are positioned around or near the woodland ride, which correctly describes their placement along the path.
Why the other options are wrong
- A. "The cheery trees stand over the woodland ride.": This sentence is not the correct option. The preposition "over" suggests that the cheery trees are positioned above or physically covering the woodland ride, which may not accurately convey the intended meaning.
- C. "The cheery trees beside about the woodland ride.": This sentence is not the correct option. The phrase "beside about" is grammatically incorrect and does not make sense in this context. The correct preposition to use in this context is "beside" or "by," but not in combination with "about."
- D. “Stand on” would incorrectly suggest the trees are literally on top of the ride.
Q15. Select the nearest corrcet meaning of the given word:EMPATHY
- A. Understanding✓
- B. Animosity
- C. Friendship
- D. Sympathy
Explanation: This option is the nearest correct meaning of the word "empathy." Empathy refers to the ability to understand and share the feelings or experiences of another person. It involves recognizing and comprehending someone else's emotions or perspective.
Why the other options are wrong
- B. This option is not the correct meaning of "empathy." Animosity refers to strong hostility or ill feelings towards someone. It is the opposite of empathy, as it involves negative emotions or antagonism rather than understanding and sharing feelings.
- C. This option is not the correct meaning of "empathy." Friendship refers to a relationship of mutual affection, trust, and support between individuals. While empathy can exist within a friendship, it is not synonymous with friendship itself.
- D. Sympathy (Wrong) - Feelings of pity and sorrow for someone else's misfortune.
Q16. Select the nearest correct meaning of the given word:FELICITY
- A. Boredom
- B. Business
- C. Happiness✓
- D. Relaxation
Explanation: Felicity means joy which is closest to happiness. (Students can confuse it with relaxation)The synonym of felicity is happiness.
Why the other options are wrong
- A. Synonyms of boredom are restlessness, weariness, blahs, melancholy, ennui, tedium,
- B. Synonyms of business corporation · factory · firm · house · institution · market · organization
- D. Synonyms of relaxation are such as: calm, lie down, loosen up, recline, sit back, and soften
Q17. Select the nearest correct meaning of the given word:UNCANNY
- A. Exact
- B. Opposite
- C. Good
- D. Strange✓
Explanation: Uncanny means unnatural or mysterious. This matches with option D i.e strange. Synonyms of uncanny are weird,unnatural,incredible, mysterious, spooky, unearthly, inexplainable, strange.OPTION D: synonyms of uncanny are weird,unnatural,incredible, mysterious, spooky, unearthly, inexplainable, strange.
Why the other options are wrong
- A. Synonyms of exact are accurate, correct, precise,nice, and right
- B. Synonyms of opposite are adverse, antagonistic, antithetical, contradictory, differing,
- C. Synonyms of good are reasonable, logical, reasoned, valid, sensible, rational, solid, hard;
Q18. Select the nearest correct meaning of the given word:VIRULENT
- A. Progressive
- B. Harmful✓
- C. Healthy
- D. Positive
Explanation: Virulent is often associated with viruses, which means it cannot be progressive, healthy or positive. Thus the correct option is B i.e harmfulSynonyms of virulent deadly,hamful, destructive, fatal, malignant, pernicious, and baneful.OPTION B: synonyms of virulent deadly,hamful, destructive, fatal, malignant, pernicious, and baneful.
Why the other options are wrong
- A. Synonyms for progressive are forward-looking · forward-thinking · left · left of center · leftist .liberal · reformist · avant-garde
- C. Synonyms of healthy are well, robust, strong, whole, sturdy, wholesome, hale, fit;
- D. Synonyms of positive yea, pro, yes, approval, acceptance, grace, favorable, good.
Q19. Select the nearest correct meaning of the given word:RAPT
- A. Trumpet
- B. Bewitched✓
- C. Rapid
- D. Rash
Explanation: Rapt means ‘fascination’ which is closely associated with being bewitched so option B is correct. Synonyms of rapt are delighted, ecstatic, enthralled, inattentive, rapturous, and spellbound, bewitched.OPTION B: synonyms of rapt are delighted, ecstatic, enthralled, inattentive, rapturous, and spellbound, bewitched.
Why the other options are wrong
- A. Synonyms of trumpet are clarion, cornet, horn, instrument, and shophar.
- C. Synonyms of rapid are accelerated, breakneck, brisk, expeditious, fast, and hasty.
- D. Synonyms of rash are audacious · bold · daring · foolhardy · hasty · ill-advised · ill-considered · immature
Q20. Select the nearest correct meaning of the given word:PEDAGOGY
- A. The study of pediatrics
- B. The study of teaching methods✓
- C. The study of cultural heritage
- D. The study of the pectoral muscle
Explanation: The study of teaching methods: This option is the nearest correct meaning of the word "pedagogy." Pedagogy refers to the study of teaching methods, principles, and practices. It encompasses the theory and practice of education, including instructional strategies, curriculum development, and classroom management.
Why the other options are wrong
- A. The study of pediatrics: This option is not the correct meaning of the word "pedagogy." Pediatrics is a branch of medicine that deals with the medical care of infants, children, and adolescents. It is unrelated to the study of teaching methods, which is the focus of pedagogy.
- C. The study of cultural heritage: This option is not the correct meaning of "pedagogy." Cultural heritage refers to the customs, traditions, artifacts, and values that are passed down from generation to generation. While education and pedagogy may be influenced by cultural heritage, they are distinct fields of study.
- D. The study of the pectoral muscle: This option is not the correct meaning of "pedagogy." The pectoral muscle is a muscle located in the chest area. It is unrelated to the study of teaching methods or education.
Q21. Select the nearest correct meaning of the given word:INDICTMENT
- A. Humiliation
- B. Offended
- C. Accusation✓
- D. Invisible
Explanation: ‘Indictment’ is a word that is closely associated with criminals and trials therefore its nearestcorret meaning is “accusation”. Synonyms of indictment are allegation, arraignment, bill, charge, citation, and detention, accusation.OPTION C: synonyms of accusation are confusion, degradation, disgrace, ignominy, indignity, and shame.
Why the other options are wrong
- A. Synonyms of humiliation are confusion, degradation, disgrace, ignominy, indignity, andshame
- B. Synonyms of offended are angry, annoyed, exasperated, insulted, outraged, and hurt
- D. Synonyms of invisible are imperceptible · microscopic · unseen · inconspicuous · unseeable · concealed · covert · deceptive
Q22. Select the nearest correct meaning of the given word:MITIGATION
- A. Alleviation✓
- B. Classification
- C. Formidable
- D. Poisonous
Explanation: Mitigation means lessening or reduction which is synonym to alleviation. Synonyms of mitigation are cure, extenuation, moderation, reduction, relief, and remission, alleviation.OPTION A: synonyms of alleviation are cure, extenuation, moderation, reduction, relief, and remission, alleviation
Why the other options are wrong
- B. Synonym of classification are allocation, allotment, analysis, arrangement, coordination,
- C. Synonym of formidable is awesome · dangerous · daunting · dire · dreadful · fierce · imposing · intimidating.
- D. Synonyms of poisonous are baleful · baneful · bloodthirsty · bloody · cannibalistic carcinogenic · cruel · dangerous
Q23. Select the nearest correct meaning of the given word:CONCERTED
- A. Strenuous✓
- B. Furious
- C. Curious
- D. Precious
Explanation: Concerted means joint/coordinated. It should be noted that furious, curious, and precious do not have the exact definition as concerted so we choose option A which is nearest to the meaning of concerted. Synonyms of concerted are united, combined, joint, planned, prearranged, agreed upon, strenous.
Why the other options are wrong
- B. Synonyms of furious are desperate, enraged, fierce, frantic, frenetic, and frenzied
- C. Synonyms of curious inquisitive · interested · analytical · disquisitive · examining ·impertinent · inquiring · inspecting
- D. Synonyms of precious are adored · beloved · cherished · darling · dear · dearest · idolized · inestimable
Q24. Select the nearest correct meaning of the given word:ARCANE
- A. Mysterious✓
- B. Furious
- C. Arid
- D. Clear
Explanation: Arcane means secret / hidden so option A correct as mysterious can be a synonym for secretsynonyms of arcane are esoteric, impenetrable, cabalistic, mysterious, mystic, and occult.
Why the other options are wrong
- B. Synonyms of furious are desperate, enraged, fierce, frantic, frenetic, and frenzied.
- C. Synonyms of arid are interesting, involving, intriguing, engaging, engrossing.
- D. Synonyms of clear are clean · cleanse · erase · purify · refine · tidy · tidy up · wipe.
Q25. In _ response, β-cells produce plasma cells that synthesize antibodies and release them in blood plasma and tissue fluid.
- A. Cell-Mediated
- B. Hormonal
- C. Humoral✓
- D. Phototactic
Explanation: This option is the correct response in the given context. Humoral response refers to the immune response involving the production of antibodies by plasma cells. In this context, β-cells are producing plasma cells that synthesize antibodies and release them into the blood plasma and tissue fluid. This accurately describes the process mentioned in the sentence.
Why the other options are wrong
- A. This option is not the correct response in the given context. Cell-mediated response typically refers to the immune response that involves the activation of immune cells, such as T-cells, to directly attack infected or abnormal cells. It does not involve the production of plasma cells and antibodies as described in the sentence.
- B. This option is not the correct response in the given context. Hormonal response typically refers to the release of hormones by endocrine glands to regulate various physiological processes in the body. It does not specifically involve the production of plasma cells and antibodies.
- D. This option is not the correct response in the given context. Phototactic refers to the movement or orientation of organisms in response to light. It is not relevant to the production of plasma cells and antibodies in the immune response.
Q26. Passive immunity is used against:
- A. Malaria
- B. Dengue
- C. Thypoid
- D. Tetanus✓
Explanation: The method of passive immunization is used to combat active infections of tetanus, infectious hepatitis, rabies, snake bite venom, etc. Passive immunization is the transfer of antibodies from one person or animal to another, providing immediate but temporary protection against a specific disease. Unlike active immunization, it does not require the recipient's own immune system to create antibodies. This can happen naturally, such as when a newborn receives antibodies from its mother.
Why the other options are wrong
- A. Treatment of malaria depends on the number of different factors that include disease severity, the particular species of Plasmodium infecting the patient and the potential for drug resistance of the various species and strains of Plasmodium. In general, it takes about two weeks of treatment to be cured of malaria.
- B. There is no specific treatment for dengue. The focus is on treating pain symptoms. Acetaminophen (paracetamol) is often used to control pain. Non-steroidal anti-inflammatory drugs like ibuprofen and aspirin are avoided as they can increase the risk of bleeding.
- C. Typhoid fever, also known as typhoid, is a disease caused by bacteria called Salmonella typhi. The only effective treatment for typhoid is antibiotics. It is usually spread through contaminated food or water.
Q27. B-lymphocytes are named due to their relationship with:
- A. Blood
- B. Bone Marrow
- C. Bursa of Fabricius✓
- D. Bile Duct
Explanation: B lymphocytes were first discovered in the Bursa of Fabricius (a structure found in birds), and they are called so with this respect.
Why the other options are wrong
- A. Blood: B-lymphocytes circulate in the blood but are not named after it.
- B. Bone Marrow: In mammals, B-lymphocytes mature in the bone marrow, but the name is not derived from it.
- D. Bile Duct: Bile ducts are unrelated to B-lymphocytes and have no role in their development or naming.
Q28. In the light-independent stage of photosynthesis, the CO₂ combines with _ to form an unstable 6-carbon intermediate.
- A. Ribulose bisphosphate✓
- B. Hexose sugar
- C. Glycerate-3-phosphate
- D. Glyceraldehyde-9-phosphate
Explanation: In the light-independent stage of photosynthesis, also known as the Calvin cycle or dark reactions, carbon dioxide (CO2) combines with a five-carbon sugar called ribulose-1,5-bisphosphate (RuBP) to form an unstable 6-carbon intermediate. The enzyme responsible for this initial reaction is ribulose-1,5-bisphosphate carboxylase/oxygenase, commonly abbreviated as Rubisco.
Why the other options are wrong
- B. This option is not the correct answer. Hexose sugar refers to a type of sugar with six carbon atoms, such as glucose or fructose. While hexose sugars are involved in various metabolic processes, they are not directly involved in the specific step mentioned in the question.
- C. This option is not the correct answer. Glycerate-3-phosphate is a three-carbon compound that is formed as an intermediate in the Calvin cycle. It is not directly involved in the initial combination of CO2 to form the six-carbon intermediate.
- D. This option is not the correct answer. Glyceraldehyde-9-phosphate is a three-carbon compound that is also formed as an intermediate in the Calvin cycle, but it is not directly involved in the initial combination of CO2 to form the six-carbon intermediate
Q29. In glycolysis, glycerate-1,3-bisphosphate is converted into glycerate-3-phosphate by losing _ phosphate molecules.
- A. 3
- B. 2
- C. 1✓
- D. 4
Explanation: In glycolysis, the conversion of glycerate-1,3-bisphosphate to glycerate-3-phosphate involves the loss of one phosphate molecule. The specific enzyme catalyzing this reaction is phosphoglycerate kinase.
Why the other options are wrong
- A. This option is not the correct answer. It states that glycerate-1,3-bisphosphate is converted into glycerate-3-phosphate by losing three phosphate molecules. However, this is not accurate. The conversion of glycerate-1,3-bisphosphate to glycerate-3-phosphate involves the removal of only one phosphate molecule.
- B. This option is not the correct answer. It suggests that glycerate-1,3-bisphosphate is converted into glycerate-3-phosphate by losing two phosphate molecules. However, this is not accurate. The conversion of glycerate-1,3-bisphosphate to glycerate-3-phosphate involves the removal of only one phosphate molecule.
- D. This option is not the correct answer. It suggests that glycerate-1,3-bisphosphate is converted into glycerate-3-phosphate by losing four phosphate molecules. However, this is not accurate. The conversion of glycerate-1,3-bisphosphate to glycerate-3-phosphate involves the removal of only one phosphate molecule.
Q30. Malate is oxidized by _ to oxaloacetate in Krebs’s Cycle.
- A. ATP
- B. NADP
- C. NAD✓
- D. FAD
Explanation: NAD (nicotinamide adenine dinucleotide) is involved in the oxidation of malate to oxaloacetate in the Krebs's Cycle. NAD acts as a coenzyme that accepts hydrogen atoms (H+) and electrons (e-) during the redox reactions in cellular respiration, including the Krebs's Cycle.
Why the other options are wrong
- A. This option is not the correct answer. ATP (adenosine triphosphate) is not directly involved in the oxidation of malate to oxaloacetate in the Krebs's Cycle. ATP is primarily known as the energy currency of the cell and is involved in energy transfer reactions rather than redox reactions.
- B. This option is not the correct answer. NADP (nicotinamide adenine dinucleotide phosphate) is not typically involved in the oxidation of malate to oxaloacetate in the Krebs's Cycle. NADP is more commonly associated with the cellular processes in photosynthesis and serves as a coenzyme in anabolic reactions.
- D. This option is not the correct answer. FAD (flavin adenine dinucleotide) is not directly involved in the oxidation of malate to oxaloacetate in the Krebs's Cycle. FAD is primarily associated with the electron transport chain, where it accepts and donates electrons during oxidative phosphorylation.
Q31. In electron transport chain, the electrons from NADH and FADH2 are passed to:
- A. Cytochrome a
- B. Cytochrome a3
- C. Coenzyme C
- D. Coenzyme Q✓
Explanation: This option is the correct answer. Coenzyme Q (also known as ubiquinone) is involved in the electron transport chain, but it acts as a carrier rather than directly accepting electrons from NADH and FADH2. Coenzyme Q transfers electrons between complex I or II and complex III in the electron transport chain.
Why the other options are wrong
- A. This option is not the correct answer. While cytochromes play a role in the electron transport chain, the specific cytochrome involved in accepting electrons from NADH and FADH2 is not cytochrome a. The transfer of electrons to cytochrome a occurs later in the electron transport chain.
- B. This option is not the correct answer. Cytochrome a3 (also known as cytochrome c oxidase) is the cytochrome involved in accepting electrons from NADH and FADH2 in the electron transport chain. It is the last cytochrome in the chain and plays a crucial role in transferring electrons to molecular oxygen (O2) to form water (H2O).
- C. This option C is not the correct answer. Coenzyme C (CoA) is not directly involved in accepting electrons from NADH and FADH2 in the electron transport chain. Coenzyme C is primarily associated with carrying acetyl groups in various metabolic reactions, particularly in the citric acid cycle (Krebs cycle).
Q32. Carriers of the respiratory chain are located on:
- A. Matrix of mitochondria
- B. Outer membrane of mitochondria
- C. Inner membrane of mitochondria✓
- D. Cytoplasmic matrix In cystic fibrosis
Explanation: The carriers of the respiratory chain are located on the inner membrane of mitochondria. This membrane is highly folded into structures called cristae, which increase its surface area and provide a platform for the respiratory chain complexes involved in electron transport and oxidative phosphorylation.
Why the other options are wrong
- A. Matrix of mitochondria: This option is not the correct answer. The matrix of mitochondria refers to the innermost compartment of the mitochondria where the citric acid cycle (also known as the Krebs cycle) occurs. The carriers of the respiratory chain are not located in the matrix of mitochondria.
- B. Outer membrane of mitochondria: This option is not the correct answer. The outer membrane of mitochondria acts as a protective barrier for the organelle but does not contain the carriers of the respiratory chain. The outer membrane primarily functions in transport and communication between the mitochondria and the rest of the cell.
- D. Cytoplasmic matrix: This option is not the correct answer. The cytoplasmic matrix refers to the fluid-filled region within the cell that surrounds the organelles, including the mitochondria. The carriers of the respiratory chain are not located in the cytoplasmic matrix.
Q33. In cystic fibrosis, liposomes-microscopic vesicles are sued which are coated with:
- A. Healthy Gene✓
- B. Chromosome
- C. Protein
- D. Carbohydrate
Explanation: In cystic fibrosis, liposomes (microscopic vesicles) can be used as a delivery system for introducing a healthy gene into cells affected by the disease. This technique, known as gene therapy, aims to replace or supplement the faulty CFTR gene responsible for cystic fibrosis with a functional one.
Why the other options are wrong
- B. This option is not the correct answer. Liposomes are not coated with chromosomes. Chromosomes are structures within cells that contain genetic material, including genes, but they are not typically used in the coating of liposomes for therapeutic purposes.
- C. This option is not the correct answer. Liposomes can be coated with proteins for various applications, but in the context of cystic fibrosis, liposomes are specifically used for delivering genetic material (such as healthy genes) rather than being coated with proteins.
- D. This option is not the correct answer. Liposomes can be coated with carbohydrates for specific purposes, but in the context of cystic fibrosis, liposomes are typically coated with a healthy gene to facilitate gene delivery.
Q34. The DNA formed by the reverse transcription is called:
- A. rDNA
- B. dDNA
- C. cDNA✓
- D. DNA
Explanation: This option is the correct answer. cDNA stands for complementary DNA. It is the DNA molecule synthesized from an RNA template by the process of reverse transcription. Reverse transcription involves the synthesis of a complementary DNA strand using an RNA template and the enzyme reverse transcriptase. The resulting cDNA represents a copy of the RNA sequence.
Why the other options are wrong
- A. This option is not the correct answer. rDNA stands for recombinant DNA, which is a DNA molecule formed by combining DNA from different sources. It is not specifically related to the process of reverse transcription.
- B. This option is not the correct answer. dDNA is not a commonly used abbreviation in biology or genetics. It does not specifically refer to DNA formed by reverse transcription.
- D. This option is not the correct answer. DNA, which stands for deoxyribonucleic acid, is the genetic material found in most organisms. While DNA is involved in various biological processes, the specific term used to describe DNA formed by reverse transcription is cDNA (complementary DNA).
Q35. Bacterial cells take up recombinant plasmids when they are treated with:
- A. CaCl2✓
- B. NaCl
- C. KCl
- D. NaOH
Explanation: CaCl2: This option is the correct answer. Bacterial cells are often treated with a solution of calcium chloride (CaCl2) during a process called "calcium chloride transformation" to increase their ability to take up recombinant plasmids. The treatment with CaCl2 helps to create temporary pores in the bacterial cell membrane, allowing the plasmids to enter the cells.
Why the other options are wrong
- B. This option is not the correct answer. Sodium chloride (NaCl) is not typically used to treat bacterial cells for plasmid uptake. NaCl is a common salt used in various laboratory procedures and for maintaining osmotic balance in biological systems but is not directly involved in plasmid uptake.
- C. This option is not the correct answer. Potassium chloride (KCl) is not typically used for treating bacterial cells to facilitate plasmid uptake. KCl is also a salt commonly used in laboratory procedures, but it does not have the same effect as CaCl2 in creating temporary pores in the cell membrane.
- D. This option is not the correct answer. Sodium hydroxide (NaOH) is a strong base that is sometimes used to lyse cells and release cellular contents, but it is not used for plasmid uptake in bacterial cells. NaOH treatment would likely cause damage to the cells rather than facilitate plasmid uptake
Q36. Which one of the following is made up of radioactively labeled nucleotides?
- A. Phage DNA
- B. Genomic Library
- C. Recombinant DNA
- D. Gene Probe✓
Explanation: A gene probe is a short DNA or RNA sequence that is complementary to a specific target sequence of DNA or RNA. Gene probes can be labeled with various markers, including radioactive nucleotides. The radioactively labeled nucleotides allow for the detection and visualization of the gene probe when it binds to its complementary target sequence.A gene probe is a short DNA or RNA sequence that is complementary to a specific target sequence of DNA or RNA. It is used to detect and identify the presence or absence of the target sequence in a sample.
Why the other options are wrong
- A. Phages (bacteriophages) are viruses that infect bacteria and have their DNA or RNA.
- B. A genomic library is a collection of cloned DNA fragments representing the entire genome of an organism.
- C. Recombinant DNA refers to the combining of DNA molecules from different sources to create a new DNA molecule.
Q37. A technique in transgenic animals in which the desired gene is inserted into the eggs of the animal is called:
- A. Embryonic Stem Cell mediated Transfer
- B. Microinjection✓
- C. Retro-virus mediated gene Transfer
- D. Virus vectors
Explanation: Microinjection: This option is the correct answer. Microinjection is a technique commonly used in transgenic animal research. In this technique, a desired gene is directly injected into the pronucleus of a fertilized egg or the nucleus of a developing embryo. The injected gene becomes incorporated into the genome of the animal, leading to the expression of the desired gene in its offspring.
Why the other options are wrong
- A. This option is not the correct answer. Embryonic stem cell-mediated transfer typically refers to the introduction of desired genetic material into embryonic stem cells, which are then used to generate transgenic animals. It does not specifically involve the direct insertion of a gene into animal eggs.
- C. This option is not the correct answer. Retrovirus-mediated gene transfer involves the use of retroviruses as vectors to deliver desired genes into host cells. While this technique can be used in gene transfer, it is not specifically associated with the direct insertion of genes into animal eggs.
- D. This option is not the correct answer. Virus vectors refer to genetically modified viruses that are used as delivery vehicles to introduce desired genes into host cells. While they can be used for gene transfer in various systems, including transgenic animals, they do not specifically involve the direct insertion of genes into animal eggs
Q38. Ozone is a layer of atmosphere extending from _ km above Earth and absorbs ultraviolet radiation.
- A. 10-50✓
- B. 50-60
- C. 5-30
- D. 10-80
Explanation: 10-50 km: This option is the correct answer. The ozone layer is a layer of the Earth's atmosphere that extends approximately 10-50 km above the Earth's surface. This layer plays a crucial role in absorbing the majority of the Sun's ultraviolet (UV) radiation, protecting life on Earth from harmful UV rays.
Why the other options are wrong
- B. 50-60 km: This option is not the correct answer. While the ozone layer extends up to approximately 50 km above the Earth's surface, it does not typically reach as high as 60 km.
- C. 5-30 km: This option is not the correct answer. The ozone layer extends beyond 5 km above the Earth's surface, but it does not typically reach as high as 30 km. The majority of the ozone layer is concentrated within the 10-50 km range.
- D. 10-80 km: This option is not the correct answer. While the ozone layer extends up to approximately 50 km above the Earth's surface, it does not typically reach as high as 80 km. The 10-50 km range is more accurate for the height of the ozone layer.
Q39. Light rays from the sun are absorbed by CO2 and re-radiate as _ radiations.
- A. Ultraviolet
- B. Indigo
- C. Infra-Red✓
- D. Green
Explanation: Infra-Red: This option is the correct answer. Light rays from the sun, including visible and ultraviolet light, can be absorbed by CO2 in the Earth's atmosphere. The absorbed energy is then re-radiated by CO2 as infrared (IR) radiation. This process contributes to the greenhouse effect and the warming of the Earth's atmosphere.
Why the other options are wrong
- A. Ultraviolet: This option is not the correct answer. Ultraviolet (UV) radiation refers to a specific range of wavelengths in the electromagnetic spectrum, which includes shorter wavelengths than visible light. While UV radiation is part of the solar radiation reaching Earth, it is not the type of radiation that is re-radiated by CO2.
- B. Indigo: This option is not the correct answer. Indigo is a color of light in the visible spectrum, but it is not specifically associated with the re-radiation of light by CO2. The absorption and re-radiation processes involving CO2 primarily occur in the infrared range rather than the visible spectrum.
- D. Green: This option is not the correct answer. Green is a color of light in the visible spectrum, but it is not specifically associated with the re-radiation of light by CO2. The absorption and re-radiation processes involving CO2 primarily occur in the infrared range rather than the visible spectrum.
Q40. The gases which are produced by burning of fossils fuels and are responsible for acid rain are:
- A. CFCs
- B. CO2 and CO
- C. HCL and Oxides of Nitrogen
- D. SO2 and Oxides of Nitrogen✓
Explanation: SO2 and Oxides of Nitrogen: This option is the correct answer. Sulfur dioxide (SO2) and nitrogen oxides (NOx) are the main gases produced by the burning of fossil fuels that contribute to acid rain. These gases are released into the atmosphere as byproducts of burning coal, oil, and gas. When they react with water vapor and other atmospheric components, they form sulfuric acid (H2SO4) and nitric acid (HNO3), respectively, which contribute to the acidity of rainwater.
Why the other options are wrong
- A. CFCs: This option is not the correct answer. While chlorofluorocarbons (CFCs) are greenhouse gases that have been implicated in ozone depletion, they are not primarily responsible for acid rain. Acid rain is caused by the presence of certain pollutants in the atmosphere, particularly sulfur dioxide (SO2) and nitrogen oxides (NOx).
- B. CO2 and CO: This option is not the correct answer. While carbon dioxide (CO2) and carbon monoxide (CO) are both produced by the burning of fossil fuels, they are not the primary gases responsible for acid rain. Acid rain is primarily caused by sulfur dioxide (SO2) and nitrogen oxides (NOx).
- C. HCl and Oxides of Nitrogen: This option is not the correct answer. Hydrochloric acid (HCl) and nitrogen oxides (NOx) can contribute to air pollution, but they are not the primary gases responsible for acid rain. Acid rain is primarily caused by sulfur dioxide (SO2) and nitrogen oxides (NOx).
Q41. During successions, the first organisms that develop on bare rock are:
- A. Lichens✓
- B. Shrubs
- C. Moss
- D. Herbs
Explanation: Lichens: This option is the correct answer. Lichens are the first organisms that typically colonize and establish on bare rock during primary succession. Lichens are a symbiotic association between fungi and algae or cyanobacteria. They can tolerate extreme environmental conditions and play a vital role in breaking down rock surfaces, contributing to the formation of soil for other plants to establish.
Why the other options are wrong
- B. Shrubs: This option is not the correct answer. Shrubs are larger woody plants that generally appear later in the process of succession. They typically follow the establishment of other plant communities, such as grasses or herbaceous plants.
- C. Moss: This option is not the correct answer. Mosses are small, non-vascular plants that can colonize bare rock surfaces and contribute to the early stages of succession. However, lichens are usually the first organisms to colonize bare rock, preceding the establishment of mosses.
- D. Herbs: This option is not the correct answer. Herbs, which refer to non-woody flowering plants, generally appear after the establishment of other plant communities during succession. They typically require a more developed soil environment to thrive.
Q42. The trophic level of a herbivore in a given food web is:
- A. 1
- B. 3
- C. 4
- D. 2✓
Explanation: D option is the correct answer. The trophic level of a herbivore is generally at the second level. Herbivores are primary consumers that directly feed on plants or algae, which occupy the first trophic level as primary producers. The energy flow in a food chain typically starts with primary producers, followed by herbivores at the second trophic level.
Why the other options are wrong
- A. 1: This option is not the correct answer. In a food web, the trophic level refers to the position of an organism in a feeding hierarchy. The first trophic level is typically occupied by primary producers, such as plants or algae, that convert energy from the sun into organic matter through photosynthesis.
- B. 3: This option is not the correct answer. The trophic level of a herbivore is not typically at the third level. Organisms at higher trophic levels usually consume other organisms, including herbivores, placing them at higher positions in the food chain.
- C. 4: This option is not the correct answer. The trophic level of a herbivore is not typically at the fourth level. Organisms at higher trophic levels usually consume other organisms, including herbivores, placing them at higher positions in the food chain.
Q43. During maternal mitosis, nondisjunction of autosomal chromosome pair results in the formation of an egg having 24 chromosomes in:
- A. Klinefelter’s Syndrome
- B. Down’s Syndrome✓
- C. Turner’s Syndrome
- D. Jacob’s Syndrome
Explanation: Down’s Syndrome involves a child receiving an extra copy of their 21st chromosome.Klinefelter's syndrome is a genetic disorder that occurs in males and is characterized by the presence of an extra X chromosome, resulting in a chromosomal configuration of XXY.Down syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of an extra copy of chromosome 21 . Chromosomes are small "packages" of genes in the body's cells, which determine how the body forms and functions. When babies are growing, the extra chromosome changes how their body and brain develop.Turner's syndrome, also known as monosomy X, is a genetic disorder that affects females. It occurs when one of the sex chromosomes is missing or partially missing, resulting in a chromosomal configuration of X0.Jacob's syndrome, also known as XYY syndrome, is a genetic condition that affects males. It is caused by the presence of an extra Y chromosome, resulting in a chromosomal configuration of XYY.
Why the other options are wrong
- A. Klinefelter's syndrome is a genetic disorder that occurs in males and is characterized by the presence of an extra X chromosome, resulting in a chromosomal configuration of XXY.
- C. Turner's syndrome, also known as monosomy X, is a genetic disorder that affects females. It occurs when one of the sex chromosomes is missing or partially missing, resulting in a chromosomal configuration of X0.
- D. Jacob's syndrome, also known as XYY syndrome, is a genetic condition that affects males. It is caused by the presence of an extra Y chromosome, resulting in a chromosomal configuration of XYY.
Q44. Typical symptoms like enlarged breasts and small testis in male are attributed to:
- A. Down’s Syndrome
- B. Turner’s Syndrome
- C. Klinefelter’s Syndrome✓
- D. Phenylketonuria
Explanation: Klinefelter's Syndrome is a genetic disorder that affects males and is characterized by the presence of an extra X chromosome (XXY instead of XY). This condition can lead to a variety of symptoms, including enlarged breasts (gynecomastia), small testes, and infertility.
Why the other options are wrong
- A. This option is not the correct answer. Down's Syndrome, also known as Trisomy 21, is a genetic disorder caused by the presence of an extra copy of chromosome 21. It is not typically associated with symptoms such as enlarged breasts and small testes in males.
- B. This option is not the correct answer. Turner's Syndrome is a genetic disorder that affects females and is caused by the absence or abnormality of one of the X chromosomes. It is not typically associated with symptoms such as enlarged breasts and small testes in males.
- D. This option is not the correct answer. Phenylketonuria (PKU) is a metabolic disorder caused by the inability to properly metabolize the amino acid phenylalanine. It is not typically associated with symptoms such as enlarged breasts and small testes in males.
Q45. Fluid mosaic model of plasma membrane states that protein molecules float in a fluid-like _ layer.
- A. Galactose
- B. Glucose
- C. Phospholipids✓
- D. Carbohydrate
Explanation: Fluid mosaic model of the plasma membrane described the arrangement of phospholipids in two layers, stabilized interiorly by the hydrophobic interactions while hydrophilic interactions at intracellular and extracellular faces with embedded proteins randomly.
Why the other options are wrong
- A. Galactose molecules are not present in form of layers.
- B. Glucose molecules are not present in form of layers.
- D. Carbohydrate molecules are not present in form of layers.
Q46. How many triplets of microtubules are present in centriole?
- A. Ten
- B. Eight
- C. Nine✓
- D. Seven
Explanation: The correct answer is Nine. Each centriole is a cylindrical structure composed of nine microtubule triplets arranged in a circular pattern, which contributes to its rigidity and function in cell division. Options A, B, and D are incorrect because they do not match the typical structure of a centriole, which is characterized by having exactly nine triplets, not ten, eight, or seven.
Why the other options are wrong
- A. This option is incorrect. Centrioles are not composed of ten triplets, but rather nine.
- B. This option is incorrect. Centrioles are structured with nine microtubule triplets, not eight.
- D. This option is incorrect. A centriole does not contain seven triplets; it has nine.
Q47. Turner’s syndrome is characterized by having:
- A. Trisomy 21
- B. 44 + XXY
- C. Trisomy
- D. 44 + XO✓
Explanation: Turner’s Syndrome is characterized by the complete or partial loss of one of the X chromosomes in females. Turner's syndrome, also known as 45, X, or 44 + XO, is characterized by the complete or partial absence of one of the X chromosomes in females. Instead of the usual 46 chromosomes, individuals with Turner's syndrome have 45 chromosomes, with only one X chromosome (XO) present in most cases. Turner syndrome can cause a variety of medical and developmental problems, including short height, failure of the ovaries to develop and heart defects.
Why the other options are wrong
- A. This option is not the correct answer. Trisomy 21 refers to a genetic condition known as Down syndrome, where individuals have an extra copy of chromosome 21. Turner's syndrome is a different genetic condition and is not associated with trisomy 21.
- B. This option is not the correct answer. 44 + XXY karyotype does not correspond to Turner's syndrome. This karyotype is associated with Klinefelter syndrome, where individuals have an extra X chromosome (XXY) in addition to the usual 44 autosomes.
- C. This option is not the correct answer. "Trisomy" refers to the presence of an extra chromosome in a set of chromosomes. However, Turner's syndrome does not involve a trisomy. It is a condition caused by the complete or partial absence of one of the X chromosomes in females.
Q48. Which one of the following cell structures is involved in the synthesis of lipids?
- A. Endoplasmic Reticulum✓
- B. Golgi Complex
- C. Centriole
- D. Mitochondria
Explanation: The smooth endoplasmic reticulum is responsible for many metabolic processes including: synthesis of lipids, phospholipids as in plasma membranes, and steroids.The cell structure involved in the synthesis of lipids is the endoplasmic reticulum (ER). On the other hand, the Golgi body is responsible for modification and packing. The centriole is involved in the division process and helps in the formation of spindle fibres Mitochondrion is involved in the formation of ATP for energy expenditure processes.
Why the other options are wrong
- B. The Golgi apparatus is involved in the synthesis, modification, and packaging of conjugated molecules such as glycoproteins and lipoproteins for transport within or outside the cell.
- C. Centrioles are cylindrical structures in animal cells that play a key role in organizing microtubules during cell division, helping in the formation of the spindle apparatus. They also assist in the formation of cilia and flagella.
- D. Mitochondrion produces ATP through cellular respiration, providing energy for the cell's metabolic and energy-requiring processes.
Q49. Monosaccharide's are major components of:
- A. DNA, ATP, Ribulose bisphosphate and Cysteine
- B. DNA, NAD and Insulin
- C. DNA, NADP, ATP and Ribulose bisphosphate✓
- D. DNA, RNA and Myosin
Explanation: Monosaccharides are simple sugars that serve as building blocks for more complex carbohydrates. In the context of cellular molecules, ATP and NADP contain ribose, a monosaccharide, and Ribulose bisphosphate is a sugar involved in photosynthesis. DNA, while containing deoxyribose, is included in the correct answer option because it is partly composed of sugar units. Other options are incorrect because they include components like proteins or amino acids, which do not contain monosaccharides.
Why the other options are wrong
- A. While ATP and Ribulose bisphosphate contain monosaccharides (ribose and ribulose, respectively), DNA contains deoxyribose, and cysteine is an amino acid, not a sugar.
- B. NAD contains a ribose sugar, but DNA contains deoxyribose, and insulin is a protein hormone, not a sugar-based molecule.
- D. RNA contains ribose, a monosaccharide, but DNA contains deoxyribose, and myosin is a protein, not related to sugars.
Q50. Blood group antigen contains:
- A. Glycoproteins✓
- B. Phospholipids
- C. Glycolipids
- D. Sphingolipids
Explanation: The correct answer is glycoproteins. Blood group antigens are mainly composed of glycoproteins, which include protein structures linked with carbohydrate chains crucial for identifying blood groups on the surface of red blood cells. Phospholipids, while essential for forming cell membranes, do not define blood group antigens. Glycolipids, though they have carbohydrate components, are not the primary molecules for blood group identity. Sphingolipids play a role in membrane integrity but do not directly participate in blood group antigen determination.
Why the other options are wrong
- B. Phospholipids form the basic structural framework of cell membranes but do not contribute to the specific identity of blood group antigens.
- C. Glycolipids have carbohydrate chains and are present on cell membranes, but they do not primarily define blood group antigens.
- D. Sphingolipids contribute to membrane structure and stability but are not directly involved in the determination of blood group antigens.
Q51. Myosin is a _ type of protein.
- A. Intermediate
- B. Simple
- C. Globular
- D. Fibrous✓
Explanation: Fibrous: This option is the correct answer. Fibrous proteins are characterized by their elongated, thread-like structure. Examples of fibrous proteins include collagen, keratin, and fibrin. Myosin has a fibrous structure and is classified as a fibrous protein. Fibrous: This option is the correct answer. Fibrous proteins are characterized by their elongated, thread-like structure. Examples of fibrous proteins include collagen, keratin, and fibrin. Myosin has a fibrous structure and is classified as a fibrous protein.
Why the other options are wrong
- A. Intermediate: This option is not the correct answer. Intermediate proteins are a type of filament protein found in the cytoskeleton of cells, such as intermediate filaments. Myosin does not belong to the category of intermediate proteins.
- B. Simple: This option is not the correct answer. "Simple" is not a specific classification for proteins. Proteins can be categorized into various types based on their structure, function, or other characteristics. Myosin does not fall into the category of simple proteins.
- C. Globular: This option is not the correct answer. Globular proteins have a compact, rounded shape and are typically soluble in water. They often have a specific three-dimensional structure and perform various functions in cells. Myosin is a motor protein involved in muscle contraction and other cellular movements.
Q52. Which one of the following is an example of unsaturated fatty acid?
- A. Butyric Acid
- B. Oleic Acid✓
- C. Palmitic Acid
- D. Acetic Acid
Explanation: Correct answer is Oleic Acid as it is a monounsaturated fatty acid.The example of an unsaturated fatty acid among the options provided is Oleic acid.Unsaturated fatty acids are a type of fatty acid that contains one or more double bonds in their carbon chain.Butyric acid is a saturated fatty acid. It is a four-carbon chain fatty acid with no double bonds.Oleic acid is an unsaturated fatty acid. It is an eighteen-carbon chain fatty acid with one double bond located between the ninth and tenth carbon atoms from the methyl (CH3) end of the chain.Palmitic acid is a saturated fatty acid. It is a sixteen-carbon chain fatty acid with no double bonds.Acetic acid is not a fatty acid. It is a simple organic compound known as a carboxylic acid, with the chemical formula CH3COOH. It is the primary component of vinegar.
Why the other options are wrong
- A. Butyric acid is a saturated fatty acid. It is a four-carbon chain fatty acid with no double bonds.
- C. Palmitic acid is a saturated fatty acid. It is a sixteen-carbon chain fatty acid with no double bonds.
- D. Acetic acid is not a fatty acid. It is a simple organic compound known as a carboxylic acid, with the chemical formula CH3COOH. It is the primary component of vinegar.
Q53. Number of base pairs in one turn of DNA is:
- A. 10✓
- B. 2
- C. 34
- D. 54
Explanation: A option is the correct answer. The number of base pairs in one turn of DNA is approximately 10.5 base pairs. This means that each complete turn of the DNA double helix consists of approximately 10.5 base pairs.
Why the other options are wrong
- B. This option is not the correct answer. The number of base pairs in one turn of DNA is not 2. The double helix structure of DNA consists of two strands that are intertwined, and each base on one strand is paired with a complementary base on the other strand.
- C. This option is not the correct answer. The number of base pairs in one turn of DNA is not 34. The actual number of base pairs required to complete one full turn of the DNA double helix is different.
- D. This option is not the correct answer. The number of base pairs in one turn of DNA is not 54. In fact, it takes less base pairs to complete one turn of the DNA double helix.
Q54. The Lymph vessel of the villi is called
- A. Lacteal✓
- B. Epithelium
- C. Adenoids
- D. Afferent lymph vessel
Explanation: The lymph vessel within the villi of the small intestine is called a lacteal. It plays a role in absorbing dietary fats.
Why the other options are wrong
- B. Epithelium refers to the tissue that lines the surfaces of organs, and it's not specifically related to the lymph vessels within villi.
- C. Adenoids are a part of the lymphatic system, but they are not related to the lymph vessels within the villi.
- D. Afferent lymph vessels bring lymph fluid into lymph nodes, but they are not specific to the villi.
Q55. Right atrium is seperated from right ventricle by:
- A. Bicuspid valve
- B. Tricuspid Valve✓
- C. Semilunar valve
- D. Interatrial Septum
Explanation: The right atrium is separated from the right ventricle by the tricuspid valve. The tricuspid valve is a three-leaflet valve that allows blood to flow from the right atrium to the right ventricle. The tricuspid valve is located at the opening of the right ventricle. The tricuspid valve is made up of three leaflets, which are called the septal leaflet, the anterior leaflet, and the posterior leaflet. The leaflets are attached to the papillary muscles by chordae tendineae. The papillary muscles are attached to the walls of the right ventricle.
Why the other options are wrong
- A. No, the right atrium is separated from the right ventricle by the tricuspid valve. The bicuspid valve, also known as the mitral valve, is a heart valve that allows blood to flow from the left atrium to the left ventricle during atrial systole. It is located between the left atrium and the left ventricle.
- C. No, the right atrium and right ventricle are not separated by a semilunar valve. The semilunar valves are located at the base of the aorta and pulmonary artery, and they prevent blood from flowing back into the ventricles. The right atrium and right ventricle are separated by the tricuspid valve.
- D. The right atrium is not separated from the right ventricle by the interatrial septum. The interatrial septum is a wall of tissue that separates the right and left atria of the heart. The right ventricle is separated from the left ventricle by the interventricular septum.The interventricular septum is made up of both muscular and fibrous tissue. The muscular tissue is responsible for the contraction of the septum, while the fibrous tissue provides structural support.
Q56. The flaps of the tricuspid valves are attached to muscular extensions of the right ventricle known as:
- A. Smooth Muscles
- B. Papillary Muscles✓
- C. Intercostal Muscles
- D. Skeletal Muscles
Explanation: This option is the correct answer. The flaps of the tricuspid valves are attached to muscular extensions of the right ventricle known as papillary muscles. Papillary muscles are specialized muscles located within the ventricles of the heart. They are connected to the tricuspid valve by cord-like structures called chordae tendineae. The contraction of the papillary muscles prevents the backflow of blood by keeping the tricuspid valve closed during ventricular contraction.
Why the other options are wrong
- A. This option is not the correct answer. Smooth muscles are a type of muscle tissue found in various organs of the body, such as the walls of blood vessels, digestive organs, and the respiratory tract. They are not directly involved in the attachment of the flaps of the tricuspid valves.
- C. This option is not the correct answer. Intercostal muscles are muscles located between the ribs. They are involved in the movement of the ribcage during respiration and are not directly related to the attachment of the flaps of the tricuspid valves.
- D. This option is not the correct answer. Skeletal muscles are the muscles attached to the skeleton and are responsible for voluntary movements. They are not directly involved in the attachment of the flaps of the tricuspid valves.
Q57. One complete heartbeat consists of one systole and one diastole and lasts for about:
- A. 0.8 sec✓
- B. 0.2 sec
- C. 0.4 sec
- D. 0.5 sec
Explanation: 0.8 seconds: This option is the correct answer. One complete heartbeat, which includes one systole (contraction) and one diastole (relaxation) of the heart, typically lasts for 0.8 seconds.
Why the other options are wrong
- B. 0.2 seconds: This option is not the correct answer. One complete heartbeat does not typically last for only 0.2 seconds. The duration of a complete heartbeat is longer than this.
- C. 0.4 seconds: This option is not the correct answer. One complete heartbeat does not typically last for exactly 0.4 seconds. The actual duration of a complete heartbeat is different.
- D. 0.5 seconds: This option is not the correct answer. One complete heartbeat, including one systole and one diastole, does not last approximately 0.5 seconds.
Q58. The heartbeat cycle starts when electric impulses are generated from:
- A. AV Node
- B. SV Node
- C. SA Node✓
- D. PQ Node
Explanation: SA Node: This option is the correct answer. The SA (sinoatrial) node, also known as the natural pacemaker of the heart, is the initial site where electric impulses are generated to start the heartbeat cycle. The SA node is located in the right atrium of the heart and sends electrical signals that cause the atria to contract.
Why the other options are wrong
- A. AV Node: This option is not the correct answer. The AV (atrioventricular) node is an important part of the electrical conduction system of the heart, but it is not the initial site where electric impulses are generated to start the heartbeat cycle.
- B. SV Node: This option is not the correct answer. There is no specific node called the SV (Sinus Venosus) Node involved in the generation of electrical impulses for the heartbeat cycle.
- D. PQ Node: This option is not the correct answer. There is no specific node called the PQ Node involved in the generation of electrical impulses for the heartbeat cycle.
Q59. About 70-85% CO2 in blood is carried:
- A. As carboxylase myoglobin
- B. Freely as CO2
- C. With proteins in plasma
- D. As bicarbonate✓
Explanation: About 70% of CO2 is transported as bicarbonate ions.
Why the other options are wrong
- A. It is not carried out as carboxylase myoglobin
- B. CO2 is not transported freely instead it is bound to substances such as bicarbonates and blood plasma etc
- C. CO2 is not carried by proteins
Q60. Those nephrons that are present along the border of the cortex and medulla are called:
- A. Juxtamedullary nephrons✓
- B. Cortical nephrons
- C. Internal nephrons
- D. Outer nephrons
Explanation: Option A is correct.Juxtamedullary nephrons are nephrons that are located at the border of the cortex and medulla of the kidney. These nephrons have a long loop of Henle that extends deep into the medulla. They play an important role in concentrating urine and regulating water balance.
Why the other options are wrong
- B. This option is not the correct answer. Cortical nephrons are nephrons that are located primarily within the renal cortex of the kidney. They have a shorter loop of Henle that does not extend deep into the medulla.
- C. This option is not the correct answer. "Internal nephrons" is not a specific term used to describe a type of nephron in the kidney.
- D. This option is not the correct answer. "Outer nephrons" is not a specific term used to describe a type of nephron in the kidney.
Q61. When water is in short supply, increased water retention occurs through the:
- A. Cortical nephrons
- B. Proximal Convoluted Tubule
- C. Juxtamedullary nephrons✓
- D. The tissue of cortex
Explanation: Juxtamedullary nephrons have long loops of Henle that extend deep into the medulla, enabling them to create a strong osmotic gradient for water reabsorption and conserve water when the body is dehydrated. Cortical nephrons have shorter loops and are less involved in water conservation.
Why the other options are wrong
- A. Cortical nephrons are a type of nephron in the kidney, but they are not directly involved in water retention. Cortical nephrons have a shorter loop of Henle and do not play a significant role in concentrating urine or regulating water balance.
- B. The proximal convoluted tubule (PCT) is an important part of the nephron located in the renal cortex. While the PCT reabsorbs a significant amount of water, it does not directly regulate water retention. The reabsorption in the PCT is typically a passive process that occurs regardless of the body's hydration status.
- D. While the tissue of the cortex contains various structures, including nephrons, it is not directly involved in water retention. The specific structures and mechanisms involved in water retention are located within the nephrons and associated structures of the kidney.
Q62. In nephrons, counter-current multiplier occurs at:
- A. Loop of Henle✓
- B. Collecting Duct
- C. Bowman’s Capsule
- D. Glomerulus
Explanation: The counter‑current multiplier system operates in the loop of Henle, where the opposing flow of fluid in the descending and ascending limbs creates and maintains a concentration gradient in the renal medulla, enabling water reabsorption and urine concentration.
Why the other options are wrong
- B. The collecting duct is involved in the final stages of urine concentration by reabsorbing water, but it does not generate the counter-current multiplier effect. Instead, it utilizes the gradient established by the Loop of Henle.
- C. Bowman's capsule is the site where blood filtration occurs, starting the urine formation process. It does not participate in the counter-current multiplier mechanism, as this occurs in later parts of the nephron.
- D. The glomerulus is a network of capillaries responsible for filtering blood. It is not involved in the counter-current multiplier mechanism, which is specific to the Loop of Henle in the nephron.
Q63. Ascending loop of Henle does not allow outflow of:
- A. Na+ ions
- B. K+ ions
- C. Cl- ions
- D. Water✓
Explanation: The ascending limb of the loop of Henle is impermeable to water, so water cannot pass through it. However, it actively reabsorbs Na⁺, K⁺, and Cl⁻ ions (via the Na⁺ K⁺-2Cl⁻ cotransporter).
Why the other options are wrong
- A. The ascending loop of Henle actively reabsorbs sodium (Na+) ions from the tubular fluid back into the bloodstream. This reabsorption of sodium contributes to the creation of a concentration gradient in the kidney medulla, allowing for water reabsorption in the collecting duct.
- B. The ascending loop of Henle also reabsorbs potassium (K+) ions from the tubular fluid back into the bloodstream. This reabsorption helps to maintain the electrolyte balance in the body.
- C. The ascending loop of Henle actively reabsorbs chloride (Cl-) ions from the tubular fluid back into the bloodstream. This reabsorption, along with the reabsorption of sodium, contributes to the generation of the concentration gradient in the kidney medulla.
Q64. A larger quantity of dilute urine is produced in diabetes insipidus. This disease is due to the deficiency of:
- A. Antidiuretic Hormone✓
- B. Aldosterone
- C. Thyroxine
- D. Cortisol
Explanation: Option A is correct.Diabetes insipidus is a condition characterized by the deficiency or dysfunction of antidiuretic hormone (ADH), also known as vasopressin. ADH is produced by the hypothalamus and released by the posterior pituitary gland. Its main function is to regulate water balance by increasing water reabsorption in the kidneys. In diabetes insipidus, the lack of ADH or the kidneys' inability to respond to it leads to the production of larger quantities of dilute urine.
Why the other options are wrong
- B. Aldosterone is a hormone produced by the adrenal glands and plays a role in regulating sodium and potassium levels in the body. It is not directly involved in the development of diabetes insipidus.
- C. Thyroxine, also known as T4, is a hormone produced by the thyroid gland and is involved in regulating metabolism. It is not directly related to the deficiency of ADH and the development of diabetes insipidus.
- D. Cortisol is a hormone produced by the adrenal glands and is involved in regulating various processes in the body, including stress response and metabolism. It is not directly linked to the deficiency of ADH and the development of diabetes insipidus.
Q65. Water and sodium ions are reabsorbed in:
- A. Urinary Bladder and Urethra
- B. Ureter
- C. Adrenal Cortex
- D. Proximal Convoluted Tubule & Collecting Duct✓
Explanation: The majority of water and sodium ion reabsorption occurs in the proximal convoluted tubule (PCT) of the nephron. Additional fine-tuning of water reabsorption (under ADH influence) happens in the collecting duct. The bladder and ureter are involved in urine storage and transport, not reabsorption. The adrenal cortex produces hormones like aldosterone (which affects sodium reabsorption) but is not a site of direct reabsorption.
Why the other options are wrong
- A. The urinary bladder and urethra are parts of the urinary system responsible for the storage and elimination of urine. Reabsorption of water and sodium ions does not occur in the urinary bladder and urethra.
- B. The ureters are the tubes that connect the kidneys to the urinary bladder. Their main function is to transport urine from the kidneys to the bladder. Reabsorption of water and sodium ions does not occur in the ureters.
- C. The adrenal cortex is the outer layer of the adrenal glands and produces hormones such as cortisol and aldosterone. While aldosterone, a hormone produced by the adrenal cortex, plays a role in sodium reabsorption in the kidneys, water and sodium reabsorption primarily occur in other parts of the kidney.
Q66. Which disease is responsible for dementia (memory loss)?
- A. Parkinson’s Disease
- B. Alzheimer’s Disease✓
- C. Epilepsy
- D. Grave’s Disease
Explanation: The disease responsible for dementia, which is characterized by memory loss and cognitive decline, is Alzheimer's disease. Alzheimer's disease is a neurodegenerative disorder that primarily affects older adults.
Why the other options are wrong
- A. Parkinson's disease is a neurodegenerative disorder that primarily affects movement.
- C. Epilepsy is a neurological disorder characterized by recurrent seizures, which are caused by abnormal electrical activity in the brain.
- D. Graves' disease is an autoimmune disorder that affects the thyroid gland, resulting in the overproduction of thyroid hormones.
Q67. Neurotransmitter secreted at the synapse outside the central nervous system is:
- A. Dopamine
- B. Androgen
- C. Polypeptide
- D. Acetylcholine✓
Explanation: Acetylcholine is a neurotransmitter that is secreted at synapses outside the central nervous system. It plays a crucial role in transmitting signals between neurons and between neurons and muscles in various parts of the body. Acetylcholine (ACh) is an important neurotransmitter that carries messages between nerve cells, affecting muscle contraction, memory, learning, arousal, and various autonomic functions like heart rate and blood pressure. It acts at neuromuscular junctions, in the central nervous system, and throughout the autonomic nervous system, being released by neurons and then broken down by an enzyme to allow for rapid signaling. Conditions like Alzheimer's disease and myasthenia gravis are associated with low acetylcholine levels.
Why the other options are wrong
- A. This option is incorrect. Dopamine is a neurotransmitter that is secreted at synapses within the central nervous system (CNS). It is involved in various brain functions, including reward, motivation, motor control, and mood regulation.
- B. This option is incorrect. Androgens are a class of hormones, such as testosterone, that are primarily involved in the development of male reproductive and secondary sexual characteristics. They are not neurotransmitters and do not typically function at synapses.
- C. This option is incorrect. While certain polypeptides can act as neurotransmitters, the term is not specific enough to identify a neurotransmitter secreted outside the central nervous system.
Q68. Conduction of action potentials from one node of Ranvier to another in myelinated neurons is through:
- A. Hyperpolarization
- B. Depolarization
- C. Resting Membrane Potential
- D. Saltatory Conduction✓
Explanation: In myelinated neurons, action potentials jump from one node of Ranvier to the next. Myelin acts as insulation, speeding up conduction by preventing continuous depolarization along the axon.
Why the other options are wrong
- A. Hyperpolarization describes a state where the membrane potential becomes more negative than the resting potential, reducing neuronal excitability. This process is not involved in the conduction of action potentials in myelinated neurons.
- B. Depolarization is an essential phase of action potential generation, where the membrane potential becomes less negative. However, it does not describe the method of action potential propagation between nodes in myelinated neurons.
- C. The resting membrane potential is the stable, baseline voltage across a neuron's membrane. While crucial for neuronal function, it does not explain the mechanism of action potential transmission in myelinated neurons.
Q69. In the following diagram of action potential in a neuron, ‘x’ depicts:
- A. Depolarization✓
- B. Polarization
- C. Repolarization
- D. Hyperpolarization
Explanation: Depolarization refers to the phase of an action potential where the membrane potential of a neuron becomes less negative or more positive. It typically occurs after the initial stimulus triggers a rapid influx of sodium ions into the cell, causing a change in the membrane potential. In the given diagram, 'x' represents depolarization.
Why the other options are wrong
- B. Polarization refers to the state of the resting membrane potential in a neuron, where the inside of the cell is negatively charged compared to the outside. It represents the electrical difference across the membrane when the neuron is at rest. In the given diagram, 'x' does not represent polarization.
- C. Repolarization refers to the phase of an action potential where the membrane potential of a neuron returns to its resting state after depolarization. During repolarization, there is a rapid efflux of potassium ions out of the cell, causing the membrane potential to become negative again.
- D. Hyperpolarization refers to a phase of the action potential where the membrane potential becomes more negative than the resting membrane potential. It typically occurs after repolarization, and it is caused by an excessive efflux of potassium ions or an influx of chloride ions. In the given diagram, 'x' does not represent hyperpolarization.
Q70. In human testis, which structure is responsible for carrying sperm from inside the testis?
- A. Seminiferous tubules
- B. Urinogenital duct
- C. Seminal Vesicles
- D. Vasa efferentia✓
Explanation: Vasa efferentia is the correct answer. The vasa efferentia are a series of ducts that connect the rete testis (a network of tubules within the testis) to the epididymis. These ducts are responsible for transporting sperm from the testis to the epididymis, where sperm maturation and storage take place.
Why the other options are wrong
- A. This option is not the correct answer. The seminiferous tubules are the coiled tubular structures located within the testes. They are responsible for the production of sperm through a process called spermatogenesis. However, they are not directly involved in carrying sperm from inside the testis.
- B. This option is not the correct answer. The term "urinogenital duct" is not a specific anatomical structure. It may refer to a general term used to describe the ducts that carry both urine and reproductive fluids in males and females. However, it does not specifically indicate the structure responsible for carrying sperm from inside the testis.
- C. This option is not the correct answer. The seminal vesicles are accessory glands located near the base of the bladder. They secrete a fluid that contributes to the formation of semen. While seminal vesicles play a role in the reproductive system, they are not directly responsible for carrying sperm from inside the testis.
Q71. In which part of human female reproductive system does fertilization occur?
- A. Ovary
- B. Cervix
- C. Uterus
- D. Fallopian tube✓
Explanation: Fertilization occurs in ampulla of fallopian tube.
Why the other options are wrong
- A. This option is incorrect. The ovary is responsible for the production of eggs (oocytes) but is not the site of fertilization. Fertilization occurs elsewhere after the egg is released.
- B. This option is incorrect. The cervix serves as a passageway between the vagina and the uterus but is not involved in the fertilization process.
- C. This option is incorrect. The uterus is where a fertilized egg implants and develops into an embryo, but fertilization itself does not occur here.
Q72. In females, FSH stimulates the ovary to produce:
- A. Progesterone
- B. Lactin
- C. Oestrogen✓
- D. Oxytocin
Explanation: Oestrogen (Estrogen) is the correct answer. FSH stimulates the ovary to produce estrogen (also spelled as oestrogen). Estrogen is a group of hormones primarily responsible for the development of secondary sexual characteristics, regulation of the menstrual cycle, and preparation of the uterus for potential pregnancy. FSH stimulates the growth and maturation of ovarian follicles, which then produce estrogen.
Why the other options are wrong
- A. This option is not the correct answer. Progesterone is primarily produced by the corpus luteum, which forms in the ovary after ovulation. It plays a crucial role in preparing the uterus for pregnancy and maintaining early pregnancy. FSH (follicle-stimulating hormone) does not directly stimulate the ovary to produce progesterone.
- B. This option is not the correct answer. "Lactin" is not a specific hormone. It may be a typographical error or a misinterpretation. If you meant "prolactin," it is a hormone primarily associated with milk production and breastfeeding, but it is not directly produced by the ovary in response to FSH.
- D. This option is not the correct answer. Oxytocin is a hormone primarily involved in various reproductive processes, such as labor contractions and milk let-down during breastfeeding. It is produced by the hypothalamus and released by the posterior pituitary gland, not directly stimulated by FSH in the ovary.
Q73. Syphilis, sexually transmitted disease is caused by:
- A. HIV
- B. Treponema pallidum✓
- C. Neisseria gonorrhoeae
- D. Type ‘2’ virus
Explanation: Syphillis is caused by the bacterium Treponema Pallidum.HIV causes AIDS. Neisseria gonorrhoeae causes Gonorrhoea and Type ‘2’ virus causes Herpes.HIV is the virus that causes HIV infection and leads to Acquired Immunodeficiency Syndrome (AIDS),Syphilis, a sexually transmitted disease, is caused by the bacterium Treponema pallidum.Neisseria gonorrhoeae is the bacterium responsible for causing the sexually transmitted infection known as gonorrhea.
Why the other options are wrong
- A. HIV is the virus that causes HIV infection and leads to Acquired Immunodeficiency Syndrome (AIDS),
- C. Neisseria gonorrhoeae is the bacterium responsible for causing the sexually transmitted infection known as gonorrhea.
- D. There is no term like type '2' virus.
Q74. In which phase of the human female menstrual cycle, endometrium prepares for the implantation of embryo?
- A. Proliferative phase
- B. Menstrual phase
- C. Secretory phase✓
- D. Ovulation phase
Explanation: From day 14 to day 28 of the menstrual cycle (secretory phase) Progesterone thickens endometrium in preparation for possible fertilization and subsequent implantation.During the secretory phase, which occurs after ovulation, the levels of progesterone rise. Progesterone stimulates the thickening and development of the endometrium, the lining of the uterus. The endometrium becomes rich in blood vessels and glandular secretions, preparing it for the potential implantation of a fertilized embryo.The proliferative phase occurs earlier in the menstrual cycle, prior to ovulation. During this phase, the levels of estrogen rise.The ovulatory phase is the phase in which ovulation occurs. It involves the release of a mature egg (ovum) from the ovary.Secretory phase, which occurs after ovulation, the levels of progesterone rise. Progesterone stimulates the thickening and development of the endometrium, the lining of the uterus. The endometrium becomes rich in blood vessels and glandular secretions, preparing it for the potential implantation of a fertilized embryo.If fertilization and implantation do not occur, hormone levels decrease towards the end of the secretory phase. This leads to the shedding of the endometrium during the subsequent menstrual phase, which marks the beginning of a new menstrual cycle.
Why the other options are wrong
- A. The proliferative phase occurs earlier in the menstrual cycle, prior to ovulation. During this phase, the levels of estrogen rise,
- B. The ovulatory phase is the phase in which ovulation occurs. It involves the release of a mature egg (ovum) from the ovary.
- D. If fertilization and implantation do not occur, hormone levels decrease towards the end of the secretory phase. This leads to the shedding of the endometrium during the subsequent menstrual phase, which marks the beginning of a new menstrual cycle
Q75. The total number of cervical and thoracic vertebrae in human vertebral column is:
- A. 7
- B. 19✓
- C. 14
- D. 33
Explanation: There are 7 vertebrae in the cervical region and 12 in the thoracic region, so 19 is the correct answer.
Why the other options are wrong
- A. The human vertebral column consists of 33 individual vertebrae, which are classified into different regions. The cervical region is located in the neck area and consists of 7 vertebrae while the thoracic region consists of 12 vertebrae.
- C. There is no specific region of the vertebral column that contains 14 vertebrae. The total number of vertebrae in the human vertebral column is 33.
- D. It represents the total number of vertebrae.
Q76. A sarcomere is the region of a myofibril between two successive:
- A. M-lines
- B. I-bands
- C. Z-lines✓
- D. T-tubules
Explanation: The correct answer is Z-lines. Z-lines, or Z-discs, define the boundaries of a sarcomere, marking where one sarcomere ends and the next begins. They are crucial for anchoring the thin filaments and maintaining the structural integrity of the myofibril. M-lines are central structures within a sarcomere and do not define its boundaries. I-bands contain only thin filaments and span across two sarcomeres without defining their limits. T-tubules are involved in signal transmission for muscle contraction but do not relate to sarcomere boundaries.
Why the other options are wrong
- A. M-lines are located at the center of the sarcomere and serve as attachment points for the thick filaments (myosin). They stabilize the thick filaments but do not mark the boundaries of a sarcomere.
- B. I-bands are regions within the sarcomere that contain only thin filaments (actin). They extend across parts of two adjacent sarcomeres but do not define the boundaries of a single sarcomere.
- D. T-tubules are not part of the sarcomere structure but are invaginations of the muscle cell membrane involved in transmitting action potentials and triggering muscle contractions.
Q77. The sarcolemma of muscle fibre folds inwards and forms a system of tubes which runs through the sarcoplasm called:
- A. Myofilaments
- B. Sarcoplasmic reticulum
- C. Z-lines
- D. Transverse tubules✓
Explanation: Transverse tubules: This option is the correct answer. The sarcolemma of a muscle fiber folds inwards at regular intervals to form invaginations called transverse tubules (T-tubules). T-tubules play a crucial role in transmitting electrical impulses (action potentials) deep into the muscle fiber, allowing for synchronous contraction of the sarcomeres.
Why the other options are wrong
- A. This option is not the correct answer. Myofilaments are the contractile proteins within the muscle fiber that are responsible for muscle contraction. They are not related to the folding of the sarcolemma or the formation of a system of tubes.
- B. This option is the correct answer. The sarcolemma of a muscle fiber folds inwards and forms a system of tubules called the sarcoplasmic reticulum (SR). The SR is a specialized type of endoplasmic reticulum that stores and releases calcium ions during muscle contraction.
- C. This option is not the correct answer. Z-lines (also known as Z-discs) are protein structures that mark the boundaries of a sarcomere, the basic contractile unit of a muscle fiber. They are not directly related to the folding of the sarcolemma or the formation of tubules.
Q78. According to the sliding filament theory, when muscle fibers are stimulated by the nervous system, which of the following changes occurs?
- A. I-bands shorten✓
- B. H-zone becomes more visible
- C. Z-lines move further apart
- D. A-bands shorten
Explanation: According to the sliding filament theory, muscle contraction involves the sliding of thin actin filaments over thick myosin filaments within the sarcomere. This process brings the Z-lines closer together, shortening the sarcomere, and results in the shortening of the I-bands. The A-bands remain constant in length because they represent the region of overlap between actin and myosin. Conversely, the H-zone, which contains only myosin filaments, narrows or disappears entirely during contraction. Therefore, the correct answer is that the I-bands shorten during muscle contraction.
Why the other options are wrong
- B. This option is incorrect. The H-zone is a lighter region within the A-band where only myosin filaments are present. During muscle contraction, the H-zone narrows or disappears as actin filaments slide over myosin filaments, making it less visible.
- C. This option is incorrect. The Z-lines, marking the boundaries of a sarcomere, come closer together during muscle contraction as actin filaments slide inward. They do not move further apart.
- D. This option is incorrect. The A-band represents the region of overlapping actin and myosin filaments. Its length remains constant during muscle contraction as the actin filaments slide inward, overlapping with the myosin filaments. The A-band does not shorten.
Q79. If lactic acid builds up in thigh muscles, it causes muscle tiredness and pain. This condition is called:
- A. Muscle Fatigue✓
- B. Tetany
- C. Cramps
- D. Oxygen debt in muscles
Explanation: Muscle Fatigue: This option is the correct answer. The condition described, where lactic acid builds up in thigh muscles, causing tiredness and pain, is known as muscle fatigue. Muscle fatigue occurs when muscles are unable to contract efficiently and sustain their performance due to various factors such as the depletion of energy stores, accumulation of metabolic byproducts like lactic acid, or inadequate oxygen supply.
Why the other options are wrong
- B. Tetany refers to a condition characterized by prolonged and involuntary muscle contractions, often due to imbalances in calcium and magnesium levels.
- C. Cramps are sudden, involuntary muscle contractions that can cause pain and discomfort.
- D. Oxygen debt in muscle refers to the amount of oxygen required by the muscles to restore normal metabolic function after intense exercise.
Q80. Thyroxine deficiency in adults results in a condition called:
- A. Cretinism
- B. Hypothyroidism
- C. Thyrotoximia
- D. Myxoedema✓
Explanation: Myxedema refers to the advanced or severe form of hypothyroidism characterized by swelling of the skin, subcutaneous tissues, and other organs. It is more commonly seen in adults.
Why the other options are wrong
- A. Cretinism is a congenital form of hypothyroidism that occurs due to a lack of thyroid hormones, particularly during early development. It can be caused by a dysfunctional thyroid gland.
- B. Hypothyroidism is a disorder characterized by inadequate production or insufficient levels of thyroid hormones, particularly thyroxine (T4), by the thyroid gland. Thyroxine plays a crucial role in regulating metabolism and controlling various bodily functions.
- C. Thyrotoxicosis, also known as hyperthyroidism, is the opposite condition, characterized by excessive production of thyroid hormones. It is caused by an overactive thyroid gland.
Q81. Alpha cells of pancreas release a hormone known as:
- A. Glucagon✓
- B. Insulin
- C. Gastrin
- D. Rennin
Explanation: Alpha cells of the pancreas release the hormone glucagon. Glucagon plays a key role in regulating blood glucose levels. It stimulates the liver to break down stored glycogen into glucose, which is then released into the bloodstream, increasing blood sugar levels.
Why the other options are wrong
- B. Insulin is released by beta cells of the pancreas, not alpha cells. Insulin helps regulate blood glucose levels by promoting the uptake of glucose from the bloodstream into cells and the storage of excess glucose as glycogen in the liver and muscles.
- C. Gastrin is a hormone released by the stomach to stimulate the secretion of gastric acid, promoting digestion. It is not produced by the alpha cells of the pancreas.
- D. Rennin, also known as chymosin, is an enzyme produced by the gastric chief cells of the stomach in infants. It helps in the digestion of milk proteins. Rennin is not related to the hormone released by the alpha cells of the pancreas.
Q82. X-linked recessive trait is:
- A. Hypophosphatemia
- B. Vitamin-D resistant rickets
- C. Hemophilia✓
- D. Diabetes Mellitus
Explanation: Hemophilia: This option is the correct answer. Hemophilia is a classic example of an X-linked recessive disorder. It leads to impaired blood clotting due to deficiencies in clotting factors, particularly factor VIII (hemophilia A) or factor IX (hemophilia B). This disorder primarily affects males because they have only one X chromosome, meaning a single recessive gene on this chromosome can manifest the disorder.The other options are not X-linked recessive traits. Hypophosphatemia can be due to various causes, not limited to X-linked inheritance. Vitamin-D resistant rickets is an X- linked dominant disorder, and Diabetes Mellitus, while having genetic influences, is not tied to X-linked recessive inheritance.
Why the other options are wrong
- A. Hypophosphatemia: This option is incorrect. Hypophosphatemia involves low phosphate levels in the blood and can result from various causes, including certain genetic conditions, but it is not an X-linked recessive trait.
- B. Vitamin-D resistant rickets: This option is incorrect. Also known as hereditary vitamin D-resistant rickets, it is inherited in an X linked dominant pattern, not as an X-linked recessive trait.
- D. Diabetes Mellitus: This option is incorrect. Diabetes Mellitus encompasses a variety of metabolic disorders leading to high blood sugar levels, and while it has genetic components, it is not specifically an X-linked recessive trait.
Q83. Human skin color is a good example of a?
- A. Sex-linked inheritance
- B. Polygenic inheritance✓
- C. X-linked inheritance
- D. Y-linked inheritance
Explanation: Polygenic inheritance: This option is the correct answer. Human skin color is a good example of polygenic inheritance. Polygenic inheritance occurs when a trait is influenced by multiple genes, each contributing a small effect. Skin color is determined by the combined effects of several genes that control the production and distribution of melanin, the pigment responsible for skin color.
Why the other options are wrong
- A. Sex-linked inheritance: This option is not the correct answer. Sex-linked inheritance refers to the inheritance of genes located on the sex chromosomes (X and Y). Human skin color is not primarily determined by genes located on the sex chromosomes.
- C. X-linked inheritance: This option is not the correct answer. X-linked inheritance refers to the inheritance of genes located on the X chromosome. While there are some genes related to pigmentation located on the X chromosome, they are not the primary determinants of human skin color.
- D. Y-linked inheritance: This option is not the correct answer. Y-linked inheritance refers to the inheritance of genes located on the Y chromosome. Genes on the Y chromosome are primarily involved in determining male-specific traits and are not directly related to human skin color.
Q84. From an evolutionary point of view, which respiratory protein is common in many organisms?
- A. Cytochrome a
- B. Cytochrome b
- C. Cytochrome c✓
- D. Cytochrome d
Explanation: Cytochrome c: This option is the correct answer. Cytochrome c is a highly conserved respiratory protein found in a wide range of organisms, including bacteria, fungi, plants, and animals. It plays a vital role in electron transport and is involved in transferring electrons between different protein complexes within the mitochondrial membrane. Due to its high level of conservation, cytochrome c is considered a common respiratory protein across diverse organisms.
Why the other options are wrong
- A. Cytochrome a: Cytochrome a is a respiratory protein found in many organisms, including bacteria and mitochondria of eukaryotic cells. It plays a role in the electron transport chain, which is involved in cellular respiration. However, it is not the most common respiratory protein in many organisms from an evolutionary point of view.
- B. Cytochrome b: Cytochrome b is another respiratory protein found in various organisms, including bacteria, plants, and animals. It is a component of the electron transport chain and is involved in transferring electrons during cellular respiration. However, it is also not the most common respiratory protein from an evolutionary perspective.
- D. Cytochrome d: Cytochrome d is a respiratory protein found primarily in certain bacteria. It is involved in the electron transport chain and plays a role in cellular respiration. However, it is not as widely distributed or as common as cytochrome c among different organisms.
Q85. Number of pairs of autosomes in humans in:
- A. 23
- B. 24
- C. 21
- D. 22✓
Explanation: The correct answer is 22 because humans have 22 pairs of autosomes, which are the non-sex chromosomes. These autosomes are numbered from 1 to 22 and contain genes that are not involved in determining the sex of an individual. The remaining pair of chromosomes is the sex chromosomes (XX in females or XY in males). Option A (23) is incorrect because it includes the pair of sex chromosomes. Option B (24) is incorrect as the total number of pairs of chromosomes in humans is 23. Option C (21) is incorrect as it suggests a reduction in chromosome number, which is not characteristic of typical human genetics.
Why the other options are wrong
- A. This is incorrect. While humans have 23 pairs of chromosomes in total, only 22 of these pairs are autosomes. The 23rd pair consists of sex chromosomes (XX or XY).
- B. This is incorrect. Humans do not have 24 pairs of chromosomes. The total number is 23 pairs, including 22 pairs of autosomes and 1 pair of sex chromosomes.
- C. This is incorrect. Humans have 23 pairs of chromosomes, including 22 pairs of autosomes. A total of 21 pairs is not possible, and abnormalities in chromosome count can lead to genetic disorders.
Q86. ABO blood system is an example of:
- A. Polygenes
- B. Multiple alleles✓
- C. Multiple genes
- D. Multiple mutation
Explanation: Option B is correct. The ABO blood system is an example of multiple alleles. Multiple alleles are different forms of the same gene. In the case of the ABO blood system, the gene is called ABO, and it has three alleles: A, B, and O. The A allele is responsible for the production of the A antigen in red blood cells. The B allele is responsible for the production of the B antigen in red blood cells. The O allele is responsible for the production of neither antigen on red blood cells. A person's blood type is determined by the alleles they inherit from their parents. If a person inherits two A alleles, they will have type A blood. If a person inherits two B alleles, they will have type B blood. If a person inherits one A allele and one B allele, they will have type AB blood. And if a person inherits two O alleles, they will have type O blood. Multiple alleles are a common occurrence in human genetics. Other examples of multiple alleles include the Rh blood group system, the MN blood group system, and the sickle cell anemia gene.
Why the other options are wrong
- A. No, the ABO blood system is not an example of polygenes. Polygenes are genes that contribute to a trait in a quantitative manner. The ABO blood system is an example of multiple alleles. Multiple alleles are different forms of the same gene. In the case of the ABO blood system, there are three alleles: A, B, and O. Each person inherits two alleles for the ABO blood system, one from each parent. The combination of alleles that a person inherits determines their blood type.
- C. No, the ABO blood system is not an example of multiple genes. The ABO blood system is an example of multiple alleles. Gene is a segment of DNA that codes for a protein. An allele is a variant of a gene. In the case of the ABO blood system, there are three alleles of the ABO gene: A, B, and O. The A allele codes for the production of the A antigen, the B allele codes for the production of the B antigen, and the O allele codes for the production of neither antigen.
- D. No, the ABO blood system is not an example of multiple mutation. Multiple mutations are when a single gene has multiple mutations. The ABO blood system is controlled by a single gene, but the gene has three different alleles: A, B, and O. These alleles are not the result of multiple mutations. The ABO blood system is an example of multiple alleles. Multiple alleles are when a single gene has more than two alleles. In the case of the ABO blood system, the gene has three alleles.
Q87. Which molecular structure of enzyme is essential for activity of enzyme?
- A. Primary structure
- B. Secondary structure
- C. Quaternary structure
- D. Tertiary structure✓
Explanation: The correct answer is the tertiary structure. The tertiary structure of an enzyme refers to its three-dimensional shape, which is vital for forming the active site. The active site is the specific region where substrates bind and reactions occur, making the tertiary structure crucial for the enzyme's catalytic activity. In contrast, the primary structure provides the amino acid sequence, but not the functional shape. The secondary structure contributes to stability but not directly to the active site formation. The quaternary structure is important only for enzymes composed of multiple subunits and is not universally required for enzyme activity.
Why the other options are wrong
- A. The primary structure is the linear sequence of amino acids in a protein. While it is essential for determining the protein's overall composition, it does not directly influence the enzyme's catalytic activity. The primary structure is a blueprint for higher-level structures but does not form the active site.
- B. The secondary structure involves local folding into alpha-helices and beta-sheets. These structures contribute to the overall stability of the enzyme but are not directly responsible for forming the enzyme's active site, where catalysis occurs.
- C. The quaternary structure involves the arrangement of multiple polypeptide chains in a protein complex. While important for some enzymes that function as multimeric complexes, it is not universally essential for enzyme activity, particularly for enzymes that function as a single polypeptide.
Q88. Which one of the following edible products is widely pasteurized?
- A. Soft drinks
- B. Mango squash
- C. Milk✓
- D. Orange Juice
Explanation: Milk: This option is the correct answer. Milk is widely pasteurized to kill harmful bacteria and increase its shelf life. Pasteurization involves heating the milk to a specific temperature for a set period of time and then rapidly cooling it. This process helps to eliminate pathogenic bacteria while retaining the nutritional value of the milk.
Why the other options are wrong
- A. Soft drinks are not typically pasteurized. They undergo a different manufacturing process that involves carbonation and the addition of preservatives. Pasteurization is not commonly applied to soft drinks.
- B. Mango squash is a concentrated fruit syrup made from mango pulp. It is typically not pasteurized, as the sugar content and pH of the syrup act as natural preservatives.
- D. Orange juice is also commonly pasteurized. Pasteurization helps to eliminate any potentially harmful microorganisms present in the juice, extending its shelf life and ensuring its safety for consumption.
Q89. Ribosomes are tiny organelles, which are involved in the synthesis of:
- A. Protein✓
- B. RNA
- C. Nucleus
- D. Nucleosome
Explanation: Ribosomes are essential cellular organelles tasked with synthesizing proteins by translating messenger RNA (mRNA) sequences into polypeptide chains. These proteins play various roles in cellular functions. The incorrect options relate to different cellular components and functions: RNA synthesis is a nuclear process, the nucleus functions as the control center of the cell, and nucleosomes are involved in DNA packaging, not protein synthesis.
Why the other options are wrong
- B. While ribosomes are composed of rRNA and proteins, their primary role is not to synthesize RNA. RNA synthesis is carried out by RNA polymerase enzymes in the nucleus.
- C. The nucleus is an organelle that contains the cell's genetic material (DNA) and controls cellular activities. It is a distinct structure and is not synthesized by ribosomes.
- D. A nucleosome is a structural unit of chromatin, consisting of a segment of DNA wound around histone proteins. It is unrelated to the protein synthesis function of ribosomes.
Q90. Which organelle is bounded by two membranes?
- A. Ribosomes
- B. Lysosomes
- C. Mitochondria✓
- D. Nucleolus
Explanation: Mitochondria are one of the organelles that are bound by two membranes. The outer membrane of mitochondria is smooth while the inner membrane has infoldings called cristae.
Why the other options are wrong
- A. This option is incorrect. Ribosomes are tiny granular structures found in the cell. They are not bounded by any membrane.They serve as the sites of protein synthesis.
- B. This option is incorrect. Lysosomes are single membrane-bounded that contain digestive enzymes, which break down worn-out organelles, cellular debris, and macromolecules.
- D. This option is incorrect. The nucleolus is a darkly stained, spherical structure found inside the nucleus of a eukaryotic cell. It has no membranous boundary, meaning it is not surrounded by a membrane. It contains ribosomal RNA (rRNA), ribosomal proteins, and DNA segments from specific chromosomes called nucleolar organizer regions. Its main function is the synthesis and assembly of ribosomal subunits.
Q91. At the beginning of nuclear division, the number of microtubule triplets in two pairs of centrioles that migrate to opposite poles are:
- A. 9
- B. 18
- C. 108
- D. 36✓
Explanation: Structure of a Centriole:Each centriole is composed of 9 microtubule triplets arranged in a cylindrical structure, forming the 9+0 arrangement.Centrioles in the Centrosome:Each centrosome contains a pair of centrioles (two centrioles).Since the cell contains two centrosomes during nuclear division (one for each pole), there are a total of 4 centrioles.Number of Microtubule Triplets:Each centriole has 9 triplets, so the total number of triplets in 4 centrioles is: 36
Why the other options are wrong
- A. As 2 pairs 18×2=36.
- B. As 2 pairs 18×2=36.
- C. As 2 pairs 18×2=36.
Q92. The disease in which an individual has extra sex chromosome (44 + XXY) is known as:
- A. Down’s syndrome
- B. Turner's syndrome
- C. Klinefelter’s syndrome✓
- D. Jacob’s syndrome
Explanation: Klinefelter's syndrome is a genetic disorder that affects males, characterized by the presence of an extra X chromosome. The most common karyotype in Klinefelter's syndrome is 47 + XXY, indicating an additional X chromosome. Individuals with Klinefelter's syndrome may have physical, hormonal, and developmental differences.
Why the other options are wrong
- A. Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of an extra copy of chromosome 21. It is characterized by distinct physical features, intellectual disability, and developmental delays. The karyotype of individuals with Down's syndrome is 47 + XX or 47 + XY.
- B. This option is not the correct answer. Turner's syndrome is a genetic disorder that affects females, characterized by the absence of one X chromosome or significant abnormalities in the X chromosome. The karyotype of individuals with Turner's syndrome is 45 + X.
- D. Jacob's syndrome, also known as XYY syndrome, is a genetic condition in males where there is an extra Y chromosome, resulting in a karyotype of 47 + XYY. This syndrome is associated with tall stature and behavioral differences, but it is generally not associated with severe physical or cognitive impairments.
Q93. Over-secretion of cortical hormone causes a disease called:
- A. Cushing’s Disease✓
- B. Diabetes Mellitus
- C. Hypoglycemia
- D. Addison’s Disease
Explanation: Cushing's Disease is caused by excess production/release of the cortisol hormone in the adrenal glands. The disease caused by the over-secretion of cortical hormones (specifically glucocorticoids) is called Cushing's disease. Cushing's disease is a condition characterized by excessive production of cortisol, which is a type of glucocorticoid hormone. It is typically caused by a tumor or abnormality in the pituitary gland, which leads to overstimulation of the adrenal glands and increased production of cortisol. Cushing's disease is a condition characterized by excessive production of cortisol, which is a type of glucocorticoid hormone.
Why the other options are wrong
- B. Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels.
- C. Hypoglycemia refers to low blood sugar levels.
- D. Addison's disease, also known as adrenal insufficiency, is a condition where the adrenal glands do not produce enough cortisol and often insufficient aldosterone.
Q94. Ejection of milk from mammary glands is under the control of which one of the following hormones?
- A. Androgen
- B. Oxytocin✓
- C. Progesterone
- D. Estrogen
Explanation: Oxytocin causes an increase in intramammary pressure through the induction of contraction of myoepithelial cells and thus aids in expelling milk from the mammary glands. The ejection of milk from the mammary glands is primarily under the control of the hormone oxytocin.
Why the other options are wrong
- A. Androgens are a group of hormones that includes testosterone. In males, androgens are primarily produced by the testes and are responsible for the development and maintenance of male sexual characteristics, such as deepening of the voice, facial and body hair growth, and sperm production.
- C. Progesterone’s main functions are to prepare and maintain the uterus for implantation of a fertilized egg, support early pregnancy by preventing uterine contractions, and promote the development of the mammary glands in preparation for breastfeeding. Progesterone also helps regulate the menstrual cycle.
- D. Estrogen plays a central role in the development of female sexual characteristics, including breast development, widening of the hips, and the onset of menstruation.
Q95. Granulocytes are:
- A. Monocytes, Eosinophils, Basophils
- B. Basophils, Macrophages, Neutrophils
- C. Neutrophils, Eosinophils, Basophils✓
- D. Monocytes, Macrophages, Basophils
Explanation: Neutrophils, Eosinophils, Basophils: This option is the correct answer. Neutrophils, eosinophils, and basophils are all types of granulocytes. They are characterized by the presence of granules in their cytoplasm and play important roles in the immune response. Neutrophils are involved in the phagocytosis of bacteria, eosinophils are involved in allergic reactions and defense against parasites, and basophils are involved in inflammatory responses.
Why the other options are wrong
- A. Monocytes, Eosinophils, Basophils: This option is not the correct answer. Monocytes are a type of agranulocyte, not a granulocyte. Granulocytes are characterized by the presence of granules in their cytoplasm. Eosinophils and basophils are granulocytes, but monocytes are agranulocytes.
- B. Basophils, Macrophages, Neutrophils: This option is not the correct answer. Macrophages are agranulocytes, not granulocytes. Basophils and neutrophils are granulocytes, but macrophages are agranulocytes.
- D. Monocytes, Macrophages, Basophils: This option is not the correct answer. Monocytes and macrophages are agranulocytes, not granulocytes. Basophils are granulocytes, but monocytes and macrophages are agranulocytes.
Q96. The response of the body against the transplanted organ is:
- A. Homeostatic Response
- B. Primary Immune Response
- C. Behavioral Response
- D. Cell-mediated Response✓
Explanation: Transplant rejection is caused primarily by a cell-mediated immune response to HLA antigens expressed on donor antigen-presenting cells (APCs) transferred along with the transplanted organ. Recognition of donor HLA antigens on the cells of the graft induces vigorous T cell proliferation in the recipient.
Why the other options are wrong
- A. A homeostatic response involves maintaining internal balance within the body and is not related to immune reactions against foreign cells or tissues.
- B. The primary immune response refers to the initial immune reaction to a new antigen, primarily involving the production of antibodies. It is not specific to transplanted organs.
- C. A behavioral response involves actions or changes in behavior to avoid pathogens, rather than a direct immune reaction to foreign tissues.
Q97. Some enzymes require helper which is non-protein part for its efficient functioning that is called:
- A. Accelerator
- B. Cofactor✓
- C. Prosthetic group
- D. Apoenzyme
Explanation: Some enzymes require non protein parts for their proper functioning. If the non-protein part is covalently bonded, it is known as a prosthetic group. If it is loosely attached to the protein part, it is known as coenzyme. Enzyme with its cofactor removed is called apoenzyme.
Why the other options are wrong
- A. This option is incorrect. An accelerator in enzymes is a substance or molecule that increases the rate of an enzymatic reaction. In other words, an accelerator can enhance the activity of an enzyme, allowing it to catalyze a reaction more quickly or efficiently.
- C. Enzymes which are not completely proteins have non protein part affiliated with them. If non protein part is bonded covalently it is known as prosthetic group. This option is incorrect.
- D. This option is incorrect. Apoenzyme is an enzyme with its prosthetic group or coenzyme removed.
Q98. Pepsin, protein digesting enzymes, sets best pH:
- A. 3.00
- B. 4.50
- C. 2.00✓
- D. 6.00
Explanation: Pepsin works best at a pH of around 2.00, which is highly acidic. The low pH helps denature proteins and allows pepsin to cleave peptide bonds efficiently.
Why the other options are wrong
- A. Pepsin, which is a protein-digesting enzyme found in the stomach, functions optimally at a pH of around 3.00. The stomach produces hydrochloric acid, which lowers the pH in the stomach and creates an acidic environment necessary for pepsin to function effectively in breaking down proteins.
- B. While the pH of the stomach can vary depending on factors such as food intake and other physiological conditions, the optimal pH for pepsin activity is lower than 4.50.
- D. A pH of 6.00 is closer to neutral or slightly acidic, and it is not within the optimal pH range for pepsin activity.
Q99. Which one of the following is an example of a competitive inhibitor?
- A. Glucose
- B. Fumarate
- C. Succinic acid
- D. Malonate✓
Explanation: Malonate has structural similarity with succinic acid and it binds competitively with the active site of succinic acid dehydrogenase enzyme and blocks its activity.
Why the other options are wrong
- A. This option is incorrect. Glucose is a simple sugar that is an important source of energy for the body. It is not a competitive inhibitor.
- B. This option is incorrect. Fumarate is a molecule involved in the citric acid cycle, which is a series of enzymatic reactions that occurs in the mitochondria of cells. It is not a competitive inhibitor.
- C. This option is incorrect. Succinic acid, also known as succinate, is another molecule involved in the citric acid cycle. It is not a competitive inhibitor.
Q100. HIV is classified as?
- A. Bacteriophage
- B. Retrovirus✓
- C. Hepatitis
- D. Icosahedral virus
Explanation: Option B is correct. Retroviruses use RNA as their genetic material and employ reverse transcriptase to form DNA, which integrates into the host genome for replication. HIV is a classic example. In contrast, bacteriophages infect bacteria, hepatitis is liver inflammation often caused by viruses (A–E), and icosahedral viruses have a capsid with 20 triangular faces, as seen in poliovirus and adenovirus.
Why the other options are wrong
- A. A bacteriophage, also known as a phage, is a virus that infects and replicates within bacteria. Phages are typically much simpler than other viruses, consisting of only a protein coat and a nucleic acid genome. The genome of a bacteriophage can be either DNA or RNA, and it can be single-stranded or double-stranded.
- C. Hepatitis is inflammation of the liver. It can be caused by a virus, bacteria, or other factors. The most common types of hepatitis are caused by viruses: hepatitis A, B, C, D, and E.
- D. An icosahedral virus is a virus that has a protein shell that is made up of 20 triangular faces. The icosahedral shape is the most common shape for viruses, and it is found in a wide variety of viruses, including poliovirus, rhinovirus, and adenovirus.
Q101. Cyanobacteria are:
- A. Photoautotrophic bacteria✓
- B. Chemosynthetic bacteria
- C. Saprotrophic bacteria
- D. Parasitic bacteria
Explanation: Cyanobacteria synthesize their own food from inorganic substances and this fall into the category of photoautotrophs.
Why the other options are wrong
- B. Chemosynthetic bacteria are a group of bacteria that obtain energy by carrying out chemosynthesis. chemosynthetic bacteria use inorganic molecules such as hydrogen sulfide, ammonia, or iron as a source of energy to convert carbon dioxide into organic compounds.
- C. Saprotrophic bacteria, also known as saprophytic bacteria, are bacteria that obtain their energy by decomposing dead organic matter.
- D. Parasitic bacteria are bacteria that live and feed off a host organism, causing harm or disease to the host. They rely on the host for nutrients and energy.
Q102. During unfavourable conditions, certain bacteria produces:
- A. Ribosomes
- B. Plasmids
- C. Mitochondria
- D. Spores✓
Explanation: Spores are specialized structures produced by certain bacteria, fungi, and other organisms during unfavorable conditions. Bacterial spores are highly resistant environmental strasses like heat, radiation, and dessication. Spore formation is a survival strategy that allows bacteria to enter a dormant state, protecting their genetic material and essential components until more favorable conditions arise. When conditions improve, spores can germinate and grow into vegetative cells again.
Why the other options are wrong
- A. This option is incorrect because ribosomes are universal cellular structures necessary for protein synthesis. They are present in all living cells, including bacteria, and are not specifically produced in response to unfavorable conditions. Bacteria need ribosomes continuously for their normal metabolic functions.
- B. This option is incorrect because plasmids are small, circular DNA molecules found in some bacteria. While they can carry advantageous genes (like those for antibiotic resistance) and can be exchanged between bacteria, they are not produced specifically during unfavorable conditions.
- C. This option is incorrect because mitochondria are organelles found in eukaryotic cells, responsible for energy production. Since bacteria are prokaryotes, they lack mitochondria entirely and do not produce them under any conditions.
Q103. In rhizopus, zygote forms temporary, dormant, thick-walled resistant structure called:
- A. Zygospore✓
- B. Spore
- C. Sporangia
- D. Hydra
Explanation: Zygospore: This option is the correct answer. In Rhizopus, the zygote undergoes sexual reproduction and forms a temporary, dormant, thick-walled resistant structure called a zygospore. The zygospore is formed through the fusion of two specialized hyphae, and it serves as a survival structure during unfavorable conditions.
Why the other options are wrong
- B. Spore: This option is not the correct answer. While Rhizopus does produce spores, the specific structure mentioned in the question is the zygospore. Spores in Rhizopus are typically formed asexually in structures called sporangia.
- C. Sporangia: This option is not the correct answer. Sporangia are structures in which spores are produced asexually in Rhizopus. However, the question is asking about the temporary, thick-walled structure formed by the zygote, which is the zygospore.
- D. Hydra: This option is not the correct answer. Hydra is a different organism and not related to the formation of zygospores in Rhizopus.
Q104. _ is a triploblastic organism.
- A. Jelly Fish
- B. Sea Anemone
- C. Tapeworm✓
- D. Corals
Explanation: Tapeworms are triploblastic organisms. They belong to the phylum Platyhelminthes and have three germ layers: ectoderm, mesoderm and endoderm. They are considered triploblastic.
Why the other options are wrong
- A. Jellyfish: This option is not the correct answer. Jellyfish belong to phylum Cnidaria. They are diploblastic and contain only two germ layers i.e, ectoderm and endoderm.
- B. Sea Anemone: This option is not correct. Sea anemones belong to phylum Cnidaria. They are diploblastic and contain only two germ layers i.e, ectoderm and endoderm.
- D. Corals: This option is not the correct answer. Corals belong to phylum Cnidaria. They are diploblastic and contain only two germ layers i.e, ectoderm and endoderm.
Q105. In arthropods, the body cavity is in the form of:
- A. Coelom
- B. Pseudocoelom
- C. Haemocoel✓
- D. Enteron
Explanation: In Arthropoda, the true coelom is greatly reduced and does not function as the main body cavity. Instead, they possess a large, blood-filled cavity called a haemocoel, which is part of an open circulatory system. In this haemocoel, tissues and organs are bathed directly in haemolymph (blood-like fluid), allowing the transport of nutrients and gases. Thus, the coelom is present only in small, reduced regions around certain organs, while the haemocoel serves as the primary body cavity in arthropods.
Why the other options are wrong
- A. A true body cavity lined with mesoderm. Arthropods typically lack a coelom.
- B. A body cavity partially lined with mesoderm. Arthropods generally don't have a pseudocoelom.
- D. The primitive body cavity or primitive gut, not directly related to the body cavity form in arthropods.
Q106. _ is a good example of polymorphism.
- A. Hydra
- B. Starfish
- C. Obelia✓
- D. Euplectella
Explanation: Polymorphism refers to the occurrence of different forms or variations within the same species. In the context of the given options, Obelia is a good example of polymorphism. Obelia is a genus of hydrozoan cnidarians, which includes various species of marine animals such as hydroids. These organisms exhibit different forms in their life cycle. The life cycle of Obelia involves both a polyp stage, where the organism is attached to a substrate and resembles a small, often colonial, organism, and a medusa stage, where the organism is free-swimming and has a bell-like body plan. The polyp and medusa stages of Obelia represent distinct forms within the same species, and this variation in form is a characteristic of polymorphism. The polyp and medusa forms serve different functions and exhibit different structures and behaviors, which is a key feature of polymorphism.
Why the other options are wrong
- A. Hydra: This option is not the correct answer. Hydra is a simple freshwater organism belonging to the phylum Cnidaria. While it exhibits some variations in size and color, it is not typically considered a good example of polymorphism. Polymorphism refers to the occurrence of different forms or morphs within a species.
- B. Starfish: This option is not the correct answer. Starfish, also known as sea stars, belong to the phylum Echinodermata. While they exhibit some variations in color and size, they are not typically considered a good example of polymorphism.
- D. Euplectella is a glass sponge and does not exhibit the same kind of polymorphism seen in Obelia.
Q107. Name common gut roundworm parasites of humans and pigs.
- A. Ascaris lumbricoides✓
- B. Lumbricus terrestris
- C. Pheretima posthuma
- D. Hirudo Medicinalis
Explanation: Ascaris lumbircoides is a large roundworm parasite that can infect both humans and pigs.
Why the other options are wrong
- B. Lumbricus territris is an earthworm species.
- C. Pheritema posthuma is a millipede species.
- D. Hirudo medicinalis is a medicinal leech species.
Q108. _ is also called liver fluke.
- A. Dugesia
- B. Fasciola✓
- C. Taenia
- D. Coral
Explanation: With few exceptions, the Platyhelminthes are parasites, mostly endoparasites, i.e., live inside their hosts. The most common examples are Taenia solium (tapeworm), Fasciola hepatica (liver luke), and Schistosoma (blood luke).
Why the other options are wrong
- A. Dugesia refers to a genus of free-living flatworms, commonly known as planarians, which are not parasitic and do not include liver flukes.
- C. Taenia is a genus of parasitic tapeworms, not liver flukes. They are distinct from Fasciola and infect the intestines rather than the liver.
- D. Coral refers to a diverse group of marine invertebrates and is unrelated to liver flukes, which are flatworms.
Q109. Oxyntic cells in stomach produce :
- A. Pepsin
- B. Pepsinogen
- C. Gastrin
- D. HCl✓
Explanation: HCL (Hydrochloric acid): This option is the correct answer. Oxyntic cells, also known as parietal cells, in the stomach are responsible for producing and secreting hydrochloric acid (HCl). HCl creates an acidic environment in the stomach, which aids in the digestion of food, activates pepsinogen to form pepsin, and helps kill bacteria present in ingested food.
Why the other options are wrong
- A. Pepsin: Pepsin is an enzyme that breaks down proteins into smaller peptides. However, it is not directly produced by oxyntic cells in the stomach.
- B. Pepsinogen: This option is not the correct answer. Pepsinogen is the inactive precursor of pepsin. Oxyntic cells in the stomach do produce and secrete pepsinogen.
- C. Gastrin: Gastrin is a hormone that stimulates the release of gastric acid in the stomach. It is produced by G cells, which are located in the stomach's gastric glands. Oxyntic cells in the stomach do not directly produce gastrin.
Q110. The hormone that inhibits the secretion of pancreatic juice is:
- A. Somatostatin✓
- B. Gastrin
- C. Thyroxine
- D. Parathormone
Explanation: This is the correct option because somatostatin inhibits the secretion of pancreatic juice by suppressing the release of digestive enzymes and hormones like insulin and glucagon from the pancreas. It acts as a regulatory hormone to maintain balance in digestive and endocrine functions.
Why the other options are wrong
- B. Gastrin is a hormone produced by the stomach, specifically by G cells located in the gastric glands. Its main function is to stimulate the secretion of gastric acid in the stomach.
- C. Thyroxin is a hormone produced by the thyroid gland. Its primary function is to regulate the body's metabolism. It plays a crucial role in controlling various processes in the body, including growth, development, and energy expenditure.
- D. Parathormone is a hormone produced by the parathyroid glands, which are located near the thyroid gland. Its main function is to regulate calcium and phosphate levels in the blood.
Q111. Trypsinogen is activated to trypsin by:
- A. HCI
- B. Mucus
- C. Enterokinase✓
- D. Gastrin
Explanation: Enterokinase is an enzyme produced by cells of the duodenum and is involved in digestion in humans and other animals. It converts trypsinogen into its active form, trypsin, resulting in the subsequent activation of pancreatic digestive enzymes.
Why the other options are wrong
- A. HCl in the stomach is responsible for the acidic medium of the stomach
- B. Mucus is responsible for neutralising the pH of the stomach
- D. Gastrin is released by stomach
Q112. The emulsification of fats is the role of:
- A. Saliva
- B. Gastrin
- C. Pancreatic juice
- D. Bile✓
Explanation: Bile secreted by liver contains bile salts which are responsible for emulsifying the fats. Emulsification of fats break down the fats into small emulsion droplets which increases the surface area for lipase to act on it and digest it.
Why the other options are wrong
- A. Saliva helps the lubrication of food and partial digestion of starch by the action of salivary amylase.
- B. Gastrin is a hormone produced by endocrine cells of the stomach and stimulates the production of gastric juice. Gastric juice is not responsible for the emulsification of fats.
- C. Pancreatic juice has a variety of enzymes, and almost every component of food is completely digested in its presence it however, it is not responsible for the emulsification of fats. It is produced by the pancreas and poured into the duodenum. This option is incorrect.
Q113. ‘Ka’ values of a few organic acids are given. The order of acid strength is:
- A. CCl3COOH > CHCl2COOH > CH2ClCOOH > CH3COOH✓
- B. CH3COOH > CHCl2COOH > CCl3COOH > CH2ClCOOH
- C. CHCl2COOH > CH3COOH > CCl3COOH > CH2ClCOOH
- D. CCl3COOH > CH3COOH > CHCl2COOH > CH2ClCOOH
Explanation: CCl3COOH > CHCl2COOH > CH2ClCOOH > CH3COOH: This option suggests that trichloroacetic acid (CCl3COOH) is the strongest acid, followed by dichloroacetic acid (CHCl2COOH), chloroacetic acid (CH2ClCOOH), and acetic acid (CH3COOH). The order is based on the increasing number of chlorine atoms attached to the carboxyl group, which increases the electron-withdrawing effect and enhances the acidity of the molecule. Therefore, this option represents the correct order of acid strength.
Why the other options are wrong
- B. CH3COOH > CHCl2COOH > CCl3COOH > CH2ClCOOH: This option suggests that acetic acid (CH3COOH) is the strongest acid, followed by dichloroacetic acid (CHCl2COOH), trichloroacetic acid (CCl3COOH), and chloroacetic acid (CH2ClCOOH). This order is the reverse of the correct order, as the increasing number of chlorine atoms should result in stronger acidity.
- C. CHCl2COOH > CH3COOH > CCl3COOH > CH2ClCOOH: This option suggests that dichloroacetic acid (CHCl2COOH) is the strongest acid, followed by acetic acid (CH3COOH), trichloroacetic acid (CCl3COOH), and chloroacetic acid (CH2ClCOOH). This order is also incorrect and does not follow the trend of increasing acidity with the increasing number of chlorine atoms.
- D. CCl3COOH > CH3COOH > CHCl2COOH > CH2ClCOOH: This option suggests that trichloroacetic acid (CCl3COOH) is the strongest acid, followed by acetic acid (CH3COOH), dichloroacetic acid (CHCl2COOH), and chloroacetic acid (CH2ClCOOH). This order is the reverse of the correct order, as the increasing number of chlorine atoms should result in stronger acidity.
Q114. An organic acid ‘z’ reacts separately with sodium bicarbonate, sodium hydroxide and sodium carbonate. Which one of the following represent the structure of ‘z’?
- A. HCOOC2H5
- B. CH3―CH=CH2
- C. CH3CH2OH
- D. H3C―CH2―COOH✓
Explanation: H3C―CH2―COOH: This structure represents propanoic acid, which is an organic acid. The carboxylic acid functional group (-COOH) is present in this structure, which is characteristic of organic acids. Therefore, this option represents the correct structure of 'z'.
Why the other options are wrong
- A. HCOOC2H5: This structure represents ethyl formate, which is an ester, not an organic acid. Therefore, this option is incorrect.
- B. CH3―CH=CH2: This structure represents propene, which is an alkene and not an organic acid. Therefore, this option is also incorrect.
- C. CH3CH2OH: This structure represents ethanol, which is an alcohol and not an organic acid. Therefore, this option is incorrect.
Q115. Carboxylic acids are rather hard to reduce, which powerful reducing agent can be used to convert them to the corresponding primary alcohol:
- A. H2SO4 / HgSO4
- B. V2O5
- C. LiAlH4✓
- D. K2Cr2O7 /H2SO4
Explanation: LiAlH4 : Lithium aluminum hydride (LiAlH4) is a powerful reducing agent commonly used to convert carbonyl compounds, including carboxylic acids, to their corresponding primary alcohols. This option represents the correct reducing agent for the conversion.
Why the other options are wrong
- A. H2SO4 /HgSO4 : This combination of sulfuric acid ( H2SO4 ) and mercuric sulfate (HgSO4 ) is not a powerful reducing agent. It is commonly used in the Clemmensen reduction, which converts carbonyl compounds (aldehydes/ketones) to alkanes, but it is not effective in reducing carboxylic acids to primary alcohols. Therefore, this option is incorrect.
- B. V2O5 : Vanadium pentoxide ( V2O5 ) is not a reducing agent. It is often used as a catalyst in various chemical reactions but does not have the ability to convert carboxylic acids to primary alcohols. Therefore, this option is incorrect.
- D. K2Cr2O7 /H2SO4 : This combination of potassium dichromate (K2Cr2O7 ) and sulfuric acid (H2SO4 ) is not a reducing agent but rather an oxidizing agent commonly used in the Jones oxidation. It is used to oxidize primary and secondary alcohols to aldehydes and ketones, respectively. Therefore, this option is incorrect.
Q116. This structure is:
- A. Gly-Ala (dipeptide)✓
- B. Asp-Gly (dipeptide)
- C. Gly-Val (dipeptide)
- D. Asp-Val (dipeptide)
Explanation: Glycine is HO2CCH2NH2 and Alanine is CH3-CH(NH2)-COOH. Hence when these two amino acids form a dipeptide bond they make the structure above.
Why the other options are wrong
- B. Incorrect
- C. Incorrect
- D. Incorrect
Q117. Which one of the following amino acids is basic in nature?
- A. glycine
- B. alanine
- C. lysine✓
- D. glutamic acid
Explanation: Lysine is a basic amino acid. It has a side chain with an amino group (-NH2) which can accept a proton (H+) and make the amino acid basic in nature. Lysine has a positively charged amino group at physiological pH, which contributes to its basicity. Therefore, lysine is the basic amino acid.
Why the other options are wrong
- A. Glycine is the simplest amino acid and it is not considered basic or acidic. It is neutral in nature as it has a hydrogen atom as its side chain. Therefore, glycine is not the basic amino acid.
- B. Alanine is a nonpolar amino acid and it is not basic in nature. It has a nonpolar side chain composed of a methyl group (-CH3). Therefore, alanine is not the basic amino acid.
- D. Glutamic acid is an acidic amino acid. It has a side chain with a carboxyl group (-COOH) which can release a proton (H+) and make the amino acid acidic in nature. Glutamic acid has a negatively charged carboxyl group at physiological pH, which contributes to its acidity. Therefore, glutamic acid is not the basic amino acid.
Q118. Which one of the following structures shows the correct formula of glutamic acid?
- A. A
- B. B✓
- C. C
- D. D
Explanation: Glutamic acid is HOOC−CH(NH2)−(CH2)2−COOH.
Why the other options are wrong
- A. Incorrect.
- C. Incorrect.
- D. Incorrect.
Q119. Select the correct Zwitter ionic structures of an amino acid:
- A. A
- B. B✓
- C. C
- D. D
Explanation: An amino acid has both a basic amine group and an acidic carboxylic acid group. There is an internal transfer of a hydrogen ion from the -COOH group to the -NH2 group to leave an ion with both a negative charge and a positive charge. This is called a zwitterion.
Why the other options are wrong
- A. Incorrect.
- C. Incorrect.
- D. Incorrect.
Q120. How many moles of sodium are present in 0.1 g of sodium?
- A. 4.3 ×10-3✓
- B. 4.03 ×10-1
- C. 4.01 ×10-2
- D. 4.3 × 10-2
Explanation: To calculate the number of moles of sodium present in 0.1g of sodium, we need to use the molar mass of sodium (Na), which is approximately 22.99 g/mol.The number of moles (n) can be calculated using the formula:n = mass / molar massn = 0.1g / 22.99 g/moln ≈ 0.00434 molRounded to two decimal places, the number of moles of sodium in 0.1g of sodium is approximately 0.0043 mol.4.3 x 10-3 (0.0043) - This matches the calculated value.
Why the other options are wrong
- B. 4.03 x 10-1 (0.403) - This value is much larger than the calculated value.
- C. 4.01 x 10-2 (0.0401) - This value is larger than the calculated value.
- D. 4.3 x 10-2 (0.043) - This value is larger than the calculated value.
Q121. The structural formula for alanine is:
- A. A Option
- B. B Option
- C. C Option
- D. D Option✓
Explanation: This structure features a methyl group as a side chain. Alanine is CH3-CH(NH2)-COOH.
Why the other options are wrong
- A. If it intended to be Valine, the structure would have a proper isopropyl R-group, which this structure aims to depict but with incorrect notation.
- B. This structure depicts a carboxyl group in the side chain, which is characteristic of aspartic acid. Therefore, this is the structural formula for aspartic acid, not alanine.
- C. This structure has only a hydrogen atom as the side chain (R group). This is the structural formula for the simplest amino acid, glycine, not alanine.
Q122. With the help of spectral data given, calculate the mass of Neon and encircle the best option. (Percentage of 10Ne20, 10Ne21 and 10Ne22 are 90.92%, 0.26% and 8.82% respectively).
- A. 22.18 amu
- B. 21.18 amu
- C. 20.18 amu✓
- D. 22.20 amu
Explanation: relative atomic mass = (20 × 90.92 + 21 × 0.26 + 22 × 8.82) ÷ 100 = 20.179 ≈ 20.18
Why the other options are wrong
- A. To calculate the mass of neon (Ne) based on the given isotopic percentages, we need to consider the weighted average of the masses of the isotopes. The atomic masses of the three isotopes of neon are as follows:10Ne20: 20 amu 10Ne21: 21 amu 10Ne22: 22 amuUsing the given percentages, we can calculate the weighted average as follows:(90.92% * 20 amu) + (0.26% * 21 amu) + (8.82% * 22 amu) = 18.184 + 0.0546 + 1.9424 = 20.180 amuRounded to two decimal places, the calculated mass of neon is approximately 20.18 amu.
- B. To calculate the mass of neon (Ne) based on the given isotopic percentages, we need to consider the weighted average of the masses of the isotopes. The atomic masses of the three isotopes of neon are as follows:10Ne20: 20 amu 10Ne21: 21 amu 10Ne22: 22 amuUsing the given percentages, we can calculate the weighted average as follows:(90.92% * 20 amu) + (0.26% * 21 amu) + (8.82% * 22 amu) = 18.184 + 0.0546 + 1.9424 = 20.180 amuRounded to two decimal places, the calculated mass of neon is approximately 20.18 amu.
- D. To calculate the mass of neon (Ne) based on the given isotopic percentages, we need to consider the weighted average of the masses of the isotopes. The atomic masses of the three isotopes of neon are as follows:10Ne20: 20 amu 10Ne21: 21 amu 10Ne22: 22 amuUsing the given percentages, we can calculate the weighted average as follows:(90.92% * 20 amu) + (0.26% * 21 amu) + (8.82% * 22 amu) = 18.184 + 0.0546 + 1.9424 = 20.180 amuRounded to two decimal places, the calculated mass of neon is approximately 20.18 amu.
Q123. Which one of the following pairs has the same electronic configuration as possessed by Neon (Ne-10)?
- A. Na+, Cl-
- B. K+, Cl-
- C. Na+, K+
- D. Na+, F-✓
Explanation: Sodium (Na+) has the electronic configuration 1s^2 2s^2 2p^6 3s^1, while fluorine (F-) has the electronic configuration 1s^2 2s^2 2p^5. Na+ loses one electron and F- ions gain one electron from their valence shells, resulting in the same electronic configuration as neon. Therefore, this pair has the same electronic configuration as neon.
Why the other options are wrong
- A. Sodium (Na+) has the electronic configuration 1s^2 2s^2 2p^6 3s^1, while chlorine (Cl-) has the electronic configuration 1s^2 2s^2 2p^6 3s^2 3p^5. The configuration of chlorine is different from the electronic configuration of neon (Ne-10), which is 1s^2 2s^2 2p^6. Therefore, this option is incorrect.
- B. Potassium (K+) has the electronic configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1, while chlorine (Cl-) has the electronic configuration 1s^2 2s^2 2p^6 3s^2 3p^5. These configurations are different from the electronic configuration of neon (Ne-10). Therefore, this pair does not have the same electronic configuration as neon.
- C. Potassium (K+) has the electronic configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1. While, sodium has same electronic configuration as neon, but potassium does not. So, this option is imcorrect.
Q124. If the volume of a gas collected at a temperature of 600 °C and pressure of 1.05 × 105 Nm-2 is 60 dm3, what would be the volume of gas at STP (P=1.01 × 105 Nm-2, T = 273 K)?
- A. 100 dm3
- B. 75 dm3
- C. 19.5 dm3✓
- D. 51 dm3
Explanation: To find the volume of the gas at STP (Standard Temperature and Pressure), we apply the combined gas law equation:(P1 * V1) / T1 = (P2 * V2) / T2Given:P1 = 1.05 × 105 N/m2V1 = 60 dm3T1 = 873.15 K (600°C converted to Kelvin)P2 = 1.01 × 105 N/m2T2 = 273 KSolving for V2:V2 = (1.05 × 105 N/m2 * 60 dm3 * 273 K) / (1.01 × 105 N/m2 * 873.15 K) ≈ 19.5 dm3Thus, the correct volume at STP is approximately 19.5 dm3, confirming that Option C is correct. Other options do not satisfy the equation when calculated under given conditions.
Why the other options are wrong
- A. This option is incorrect. A significant increase in volume would not be expected when moving to STP conditions from such high temperature.
- B. This option is incorrect. The calculations do not support this value.
- D. This option is incorrect. It represents a smaller change in volume than expected when changing to STP conditions.
Q125. There are four orbitals s, p, d and f. Which order is correct with respect to the increasing energy of the orbitals?
- A. 4s < 4p < 4d < 4f✓
- B. 4p < 4s < 4f < 4d
- C. 4s < 4f < 4p < 4d
- D. 4f < 4s < 4d < 4p
Explanation: According to the order of increasing energy, the s orbitals have lower energy than the p orbitals. However, the d orbitals have higher energy than the p orbitals, and the f orbitals have higher energy than the d orbitals. Therefore, the correct order should be: 4s < 4p < 4d < 4f.
Why the other options are wrong
- B. This order is incorrect because it suggests that the f orbitals have lower energy than the d orbitals, which is not the case.
- C. This order is incorrect because it suggests that the f orbitals have lower energy than the p orbitals, which is not the case
- D. This order is incorrect because it suggests that the f orbitals have lower energy than the s orbitals, which is not the case
Q126. Which graph represents Boyle’s law?
- A. Option A
- B. Option B✓
- C. Option C
- D. Option D
Explanation: Boyles law states that at a fixed temperature, the volume of gas is inversely proportional to the pressure exerted by the gas.
Why the other options are wrong
- A. Incorrect as this graph does not represent boyles Law
- C. Incorrect as this graph does not represent boyles Law
- D. Incorrect as this graph does not represent boyles Law
Q127. Which one of the following hydrogen bonds is stronger than others?
- A. Option A
- B. Option B✓
- C. Option C
- D. Option D
Explanation: Electronegativity trend is F>O>N. The greater the difference between the electronegativity of bonded atoms, the stronger the bond. Fluorine is the most electronegative, hence forming the strongest hydrogen bond.
Why the other options are wrong
- A. Incorrect Electronegativity trend is F>O>N. The greater the difference between the electronegativity of bonded atoms, the stronger the bond. Fluorine is the most electronegative, hence forming the strongest hydrogen bond.
- C. Incorrect Electronegativity trend is F>O>N. The greater the difference between the electronegativity of bonded atoms, the stronger the bond. Fluorine is the most electronegative, hence forming the strongest hydrogen bond.
- D. Incorrect. As fluorine has small size and high electronegativity, it has high tendency to attract partial positive charge accumulated on H-atom. So, fluorine forms strongest H-bond.
Q128. The half - life of N2O5 at 45 °C is 24 minutes. How long will it take for sample of N2O5 to decay to 25% of its original concentration?
- A. 24 minutes
- B. 120 minutes
- C. 72 minutes
- D. 48 minutes✓
Explanation: First, find out how many half-lives it takes to reach 25% (which is 1/4) of the original concentration:- (¼) = 2 , where 'n' is the number of half-lives.(-n) Taking the logarithm of both sides:-n = log(¼) / log(2) n = log(4) / log(2) = 2Since it takes 2 half-lives to reach 25% of the original concentration, you can multiply the half-life by 2 to find the total time required:Total time = 2 * 24 minutes = 48 minutes.
Why the other options are wrong
- A. This option incorrectly assumes that one half-life is enough to reduce the concentration to 25%, but one half-life only reduces it to 50%.
- B. This option overestimates the time required, mistakenly calculating more than two half-lives.
- C. This option assumes it takes three half-lives to reach 25% concentration, which is incorrect as it only takes two half-lives.
Q129. When the change in concentration is 6 x 10-4 mol dm-3 and time for that change is 10 seconds, the rate of reaction will be:
- A. 6 × 10-3mol dm-3 sec-1
- B. 6 × 10-4 mol dm-3 sec-1
- C. 6 × 10-2 mol dm-3 sec-1
- D. 6 × 10-5 mol dm-3 sec-1✓
Explanation: 𝑟𝑎𝑡𝑒 𝑜𝑓 𝑟𝑒𝑎𝑐𝑡𝑖𝑜𝑛 = Δ𝐶/𝑡 = (6 × 10−4 )/10 = 6 × 10−5𝑚𝑜𝑙𝑑𝑚−3𝑠𝑒𝑐−1 Given: Change in concentration = 6 x 10^(-4) mol dm^(-3) Time = 10 secondsRate of reaction = Change in concentration / TimeSubstituting the given values:Rate of reaction = (6 x 10^(-4) mol dm^(-3)) / 10 secondsSimplifying:Rate of reaction = 6 x 10^(-5) mol dm^(-3) sec^(-1)Among the given options, the closest value to the calculated rate is Option D: 6 x 10^(-5) mol dm^(-3) sec^(-1).Therefore, the rate of reaction will be approximately 6 x 10^(-5) mol dm^(-3) sec^(-1).
Why the other options are wrong
- A. This option is incorrect as per explantion and calculations.
- B. This option is incorrect as per the explanation and calculations.
- C. This option is incorrect as per the explanation and calculations.
Q130. Which one of the following will have the smallest radius?
- A. Al3+
- B. Si3+✓
- C. Mg2+
- D. Na1+
Explanation: Silicon has the highest atomic number and Si3+ has the highest nuclear charge. Hence, it has the smallest radius. ion with the most protons will have the strongest pull on those electrons, resulting in the smallest radius. Silicon (Si³⁺) has the most protons (14), so it has the smallest radius.
Why the other options are wrong
- A. Aluminum has 13 protons and 13 electrons. It loses three electrons to become Al³⁺, leaving it with 10 electrons. It now has 13 protons pulling on 10 electrons. ion with the most protons will have the strongest pull on those electrons, resulting in the smallest radius. Silicon (Si³⁺) has the most protons (14), so it has the smallest radius.
- C. Magnesium has 12 protons and 12 electrons. It loses two electrons to become Mg²⁺, leaving it with 10 electrons. It now has 12 protons pulling on 10 electrons. ion with the most protons will have the strongest pull on those electrons, resulting in the smallest radius. Silicon (Si³⁺) has the most protons (14), so it has the smallest radius.
- D. Sodium starts with 11 protons and 11 electrons. It loses one electron to become Na⁺, leaving it with 10 electrons. It now has 11 protons pulling on 10 electrons. ion with the most protons will have the strongest pull on those electrons, resulting in the smallest radius. Silicon (Si³⁺) has the most protons (14), so it has the smallest radius.
Q131. Keeping in view the size of atoms, which order is correct?
- A. N > C
- B. P > Si
- C. Ar > Cl
- D. Li > Be✓
Explanation: Option D is correct because Lithium (Li) and Beryllium (Be) are in the same period, with Li positioned to the left of Be. As you move from left to right within a period, the atomic size decreases due to the increase in nuclear charge, which pulls electrons closer to the nucleus. Therefore, Li has a larger atomic size than Be.The other options are incorrect because they either misrepresent the relative sizes based on periodic trends or misplace elements in different periods or groups without considering the correct periodic trend.
Why the other options are wrong
- A. This is incorrect. Both Nitrogen (N) and Carbon (C) are in the same period of the periodic table. Atomic size decreases across a period from left to right due to increasing nuclear charge, so Carbon is larger than Nitrogen.
- B. This is incorrect. Phosphorus (P) and Silicon (Si) are in the same period. Generally, as you move across a period, atomic size decreases, but the explanation here is misleading. Phosphorus is actually smaller than Silicon.
- C. This is incorrect. Argon (Ar) and Chlorine (Cl) are both in the third period. Within a period, atomic size decreases from left to right, making Argon smaller than Chlorine.
Q132. On the basis of the oxidising power of halogens, which reaction is possible?
- A. Option A
- B. Option B✓
- C. Option C
- D. Option D
Explanation: Oxidising power of halogens decreases down the group. Iodine has the least oxidising power, followed by Br2, Cl2 and then F2.
Why the other options are wrong
- A. Incorrect. Oxidising power of halogens decreases down the group. Iodine has the least oxidising power, followed by Br2, Cl2 and then F2.
- C. Incorrect. Oxidising power of halogens decreases down the group. Iodine has the least oxidising power, followed by Br2, Cl2 and then F2.
- D. Incorrect. Oxidising power of halogens decreases down the group. Iodine has the least oxidising power, followed by Br2, Cl2 and then F2.
Q133. [Ti(H2O)6]3+ transmits:
- A. Yellow and Red light
- B. Yellow and Blue light
- C. Red and white light
- D. Red and blue light✓
Explanation: When white light is allowed to fall on [Ti(H2O)6]3+ ion, this ion absorbs the light of green and yellow colour and transmits almost purple colour. Red and Blue are transmitted.
Why the other options are wrong
- A. As per the explanation, this is not the correct option.
- B. As per the explanation, this is not the correct option.
- C. As per the explanation, this is not the correct option.
Q134. Electronic configuration of Gold [Au79] is
- A. [Xe]4f14, 5d10, 6s1✓
- B. [Xe]4f¹⁰f10, 5d¹⁰, 6s²
- C. [Xe]4f14, 5d9, 6s2
- D. [Xe]4f14, 5d10, 6s2
Explanation: Atomic number of Au is 79, its electronic configuration is1s22s22p63s23p63d104s24p64d105s25p64f145d106s1(The electronic configuration of Xe is 1s22s22p63s23p63d104s24p64d105s25p6)Hence electronic configuration of Au79 is [Xe] 4f14, 5d10, 6s1The correct electron configuration of gold (Au79) is:[Xe]4f14, 5d10, 6s1 This configuration represents the filling of electron orbitals in the order of increasing energy levels. The noble gas core notation [Xe] indicates the electron configuration of the noble gas xenon (54 electrons) up to its completed 5p orbital.
Why the other options are wrong
- B. The electronic configuration Xe 4f¹⁴ 5d⁹ 6s² corresponds to the element gold (Au) in its ground state or a slightly excited state.However, the most common and stable electron configuration of gold (Au, atomic number 79) is actually:👉 Xe4f¹⁴ 5d¹⁰ 6s¹This configuration occurs due to relativistic effects and the stability associated with a completely filled 5d subshell (5d¹⁰) and a half-filled 6s subshell (6s¹).So, while XeXeXe 4f¹⁴ 5d⁹ 6s² is close and may represent a possible excited state or less stable form, the actual configuration of gold is:Xe 4f¹⁴ 5d¹⁰ 6s¹ ✅
- C. The electronic configuration Xe 4f¹⁴ 5d⁹ 6s² corresponds to the element gold (Au) in its ground state or a slightly excited state.However, the most common and stable electron configuration of gold (Au, atomic number 79) is actually👉 Xe 4f¹⁴ 5d¹⁰ 6s¹This configuration occurs due to relativistic effects and the stability associated with a completely filled 5d subshell (5d¹⁰) and a half-filled 6s subshell (6s¹).So, while XeXeXe 4f¹⁴ 5d⁹ 6s² is close and may represent a possible excited state or less stable form, the actual configuration of gold isXe 4f¹⁴ 5d¹⁰ 6s¹ ✅
- D. The electronic configuration Xe 4f¹⁴ 5d¹⁰ 6s² corresponds to the element mercury (Hg).Atomic number of mercury: 80Full electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s²
Q135. About 80% of ammonia is used for the production of:
- A. Explosives
- B. Fertilizers✓
- C. Nylon
- D. Polymers
Explanation: About 80% of the ammonia produced by industry is used in agriculture as fertilizer. Ammonia is also used as a refrigerant gas, for the purification of water supplies, in the manufacture of plastics, explosives, textiles, pesticides, dyes and other chemicals.About 80% of ammonia is used for the production of fertilizers.Ammonia (NH3) is a key component in the production of nitrogen-based fertilizers. Ammonia can ber eacted with various substances, such as nitric acid or sulfuric acid, to produce ammonium nitrate or ammonium sulfate, which are commonly used fertilizers. These fertilizers provide essential nitrogen top lants, promoting their growth and enhancing crop yields.
Why the other options are wrong
- A. This option is incorrect. While ammonia can be used in the production of some explosives, it is not the primary use for ammonia. Other chemicals and compounds are typically used as the main ingredients in explosive formulations.
- C. This option is incorrect. Ammonia is not directly used in the production of nylon. Nylon is a synthetic polymer that is produced through a different chemical process, involving the reaction of diamines and dicarboxylic acids or their derivatives.
- D. This option is incorrect. While ammonia can be used in the production of certain polymers, it is not the primary use for ammonia. Polymers can be derived from various monomers, and the production processes can vary depending on the specific type of polymer.
Q136. Urea is the most widely used nitrogen fertilizer in Pakistan. Its composition is:
- A. NH2CO
- B. N2H5CO2
- C. N2H4CO2
- D. N2H4CO✓
Explanation: Urea, also known as carbamide, is an organic compound with the chemical formula CO(NH2)2. This amide has two –NH2 groups joined by a carbonyl (C=O) functional group.The composition of urea, which is the most widely used nitrogen fertilizer in Pakistan, is N2H4CO.Urea has the chemical formula CO(NH2)2, which can also be represented as NH2CONH2. This indicates that urea consists of two amine groups (NH2) attached to a carbonyl group (C=O). The structure of urea is shown as N2H4CO, representing the arrangement of atoms.
Why the other options are wrong
- A. This option is incorrect. NH2CO is not the correct chemical composition of urea. Urea has the molecular formula (NH2)2CO, indicating the presence of two amino groups (NH2) and one carbonyl group (CO).
- B. This option is incorrect. N2H5CO2 is not the correct chemical composition of urea. It represents a different compound altogether.
- C. This option is incorrect. N2H4CO2 is not the correct chemical composition of urea. It also represents a different compound.
Q137. During the manufacture of nitric acid, nitric oxide is oxidized to nitrogen dioxide.This reaction is given as:2NO(g) + O2(g) ⇌ 2NO2(g) ΔH = -114 kJ/molAccording to Le Chatelier’s Principle;
- A. Reaction must not be temperature dependent
- B. Reaction must be carried out at room temperature
- C. Reaction must be carried out at low temperature✓
- D. Reaction must be carried out at high temperature
Explanation: Since ΔH is negative, the reaction is exothermic. More products will be formed at lower temperatures (equilibrium will shift to the right).We can see that the reaction is exothermic, as indicated by the negative value of ΔH (enthalpy change). According to Le Chatelier's principle, if the temperature is increased, the equilibrium will shift in the direction that absorbs heat, i.e., in the backward direction.Therefore, to favor the formation of more nitrogen dioxide (NO2) and drive the reaction towards the right, it would be preferable to carry out the reaction at a lower temperature. Lowering the temperature would help to maximize the yield of nitrogen dioxide.
Why the other options are wrong
- A. This option is incorrect. According to Le Chatelier's Principle, the position of equilibrium in a chemical reaction can be influenced by changes in temperature. In this case, the reaction is exothermic (ΔH = -114 kJ/mol), meaning it releases heat. Therefore, a change in temperature will affect the equilibrium position.
- B. This option is incorrect. The reaction conditions required to achieve the desired equilibrium position cannot be determined solely based on room temperature. The specific temperature required depends on the reaction kinetics and the desired yield of the product.
- D. This option is incorrect. In an exothermic reaction like the oxidation of nitric oxide to nitrogen dioxide, increasing the temperature would favor the reverse reaction (from NO2 to NO and O2). Therefore, a high temperature would not be suitable for maximizing the production of nitrogen dioxide.
Q138. What is the percentage of nitrogen in NH3NO3?
- A. 65%
- B. 35%✓
- C. 20%
- D. 58%
Explanation: Mass of N is 14, in NH3NO3 there are two Nitrogens hence the mass of N is 28g.Mass of NH3NO3 = 14+(1x3)+14+(16x3)=79Percentage of N = 28/79 = 35%
Why the other options are wrong
- A. This option is incorrect. If NH3NO3 had 65% nitrogen, it would mean that 65% of the compound's total mass is nitrogen. However, NH3NO3 does not have such a high nitrogen content.
- C. This option is incorrect. If NH3NO3 had 20% nitrogen, it would mean that 20% of the compound's total mass is nitrogen. However, NH3NO3 does not have this nitrogen content.
- D. This option is incorrect. If NH3NO3 had 20% nitrogen, it would mean that 58% of the compound's total mass is nitrogen. However, NH3NO3 does not have this nitrogen content.
Q139. The structural formula of 2,3,4 trimethylpentane is:
- A. Option A✓
- B. Option B
- C. Option C
- D. Option D
Explanation: There are methyl groups (CH3) on carbons 2, 3 and 4 in option A only.
Why the other options are wrong
- B. In this option, methyl groups are present on carbon 2 and 4 only.
- C. In this option, methyl groups are present on carbon 2 and 3 only.
- D. In this option, methyl groups are present on carbon 2 and 3 only.
Q140. Which one of the following is a powerful electrophile used to attack on the electrons of a benzene ring?
- A. FeCl2
- B. FeCl4-
- C. Cl+✓
- D. Cl2
Explanation: When benzene reacts with a powerful electrophile like Cl+ (chlorine cation), it undergoes electrophilic aromatic substitution reactions where the positively charged carbon of Cl+ attacks the electron-rich benzene ring. This leads to the formation of chlorinated derivatives of benzene. In contrast, FeCl2 and FeCl4- act as Lewis acids, accepting electron pairs but not directly attacking benzene. Cl2 (chlorine gas) is unreactive towards benzene and does not serve as an electrophile in attacking the benzene ring.
Why the other options are wrong
- A. FeCl2 is not an electrophile itself but acts as a Lewis acid, capable of accepting an electron pair. It does not directly attack the electrons of a benzene ring.
- B. FeCl4- is not an electrophile itself but acts as a Lewis acid, capable of accepting an electron pair. It does not directly attack the electrons of a benzene ring.
- D. Cl2 (chlorine gas) is not an electrophile on its own. It is relatively unreactive towards benzene and does not directly attack the electrons of the benzene ring.
Q141. The given three hydrocarbons are:
- A. Alicyclic hydrocarbons
- B. Aromatic hydrocarbons✓
- C. Acyclic hydrocarbons
- D. Heterocyclic hydrocarbons
Explanation: Aromatic hydrocarbons are the correct answer because they contain benzene rings, which the hydrocarbons shown possess. Alicyclic hydrocarbons have non-aromatic carbon rings, acyclic hydrocarbons do not have any rings, and heterocyclic hydrocarbons contain atoms other than carbon in their ring structures. Therefore, options A, C, and D are incorrect based on the structures of the hydrocarbons provided.
Why the other options are wrong
- A. Alicyclic hydrocarbons are organic compounds containing one or more non-aromatic carbon rings.
- C. Acyclic hydrocarbons do not contain any carbon ring structures.
- D. Heterocyclic hydrocarbons are organic compounds containing one or more atoms of an element other than carbon in the ring structure.
Q142. The IUPAC name of the given compound is:
- A. 1-Chloro-2-methylpropane✓
- B. 1-Chloro-2-methylbutane
- C. Isobutyl chloride
- D. 2-Methyl-3-chloropropane
Explanation: There are 3 carbons in a chain, Cl group is bonded to the 1st carbon and methyl is bonded to the 2nd carbon. Hence, the compound is called 1-chloro-2-methylpropane.
Why the other options are wrong
- B. As per the explanation, only option a is correct.
- C. As per the explanation, only option a is correct.
- D. As per the explanation, only option a is correct.
Q143. Which one of the following was used as one of the earliest antiseptic and disinfectants?
- A. Phenol✓
- B. Ether
- C. Ethanol
- D. Methanol
Explanation: The antiseptic properties of phenol were used by Sir Joseph Lister (1827–1912).Phenol was one of the earliest disinfectants and antiseptics used in medical and surgical settings. It was first introduced by the British surgeon Joseph Lister in the 19th century as a means to prevent infection during surgeries. Lister recognized the antiseptic properties of phenol and began using it to clean wounds and surgical instruments.Ether (specifically diethyl ether) is a volatile organic compound that has been historically used as an anesthetic. Its function is to induce general anesthesia, causing loss of consciousness and a lack of pain sensation during surgical procedures.Ethanol, also known as ethyl alcohol has antimicrobial properties and is effective against a wide range of bacteria, viruses, and fungi.Methanol has various industrial uses, such as a solvent or fuel, but it is not suitable for direct use on the skin or as a disinfectant due to its toxic effects.
Why the other options are wrong
- B. Ether (specifically diethyl ether) is a volatile organic compound that has been historically used as an anesthetic. Its function is to induce general anesthesia, causing loss of consciousness and a lack of pain sensation during surgical procedures.
- C. Ethanol, also known as ethyl alcohol has antimicrobial properties and is effective against a wide range of bacteria, viruses, and fungi.
- D. methanol has various industrial uses, such as a solvent or fuel, but it is not suitable for direct use on the skin or as a disinfectant due to its toxic effects.
Q144. Which one of the following is NOT able to denature the ethanol?
- A. Methanol
- B. Lactic acid✓
- C. Pyridine
- D. Acetone
Explanation: Methanol, pyridine and acetone are able to denature ethanol.Denaturation refers to the process of rendering alcohol undrinkable or unsuitable for consumption by adding or mixing it with substances that are toxic or unpalatable. This is commonly done for various purposes such as industrial use, preventing misuse or consumption, or meeting regulatory requirements. Lactic acid is not able to denature alcohol.
Why the other options are wrong
- A. Methanol is a type of alcohol similar to ethanol, and it has the ability to denature ethanol. Denaturation involves altering the chemical properties of ethanol to make it unfit for consumption.
- C. Pyridine is a basic organic compound with a pungent odor. It is not typically used as a denaturant for ethanol.
- D. Acetone is a solvent and a common denaturant for ethanol. It is often used in commercial products as a denaturing agent to render ethanol undrinkable .
Q145. In the below reaction, the configuration of product is:
- A. 100% same of the configuration of reactant
- B. 50% retained
- C. 50% inverted
- D. 100% opposite from configuration of reactant✓
Explanation: The reaction occurs with inversion of configuration. Thus, the nucleophile approaches the electrophilic carbon atom from the back and the leaving group simultaneously departs from the front of the substrate in the SN2 mechanism.
Why the other options are wrong
- A. 100% same of the configuration of reactant is not accuring.
- B. 50% retained of the configuration of reactant is not accuring.
- C. 50% inverted of the configuration of reactant is not accuring.
Q146. How will you distinguish between methanol and ethanol?
- A. By Lucas test
- B. By silver mirror test
- C. By oxidation
- D. By Iodoform test✓
Explanation: The solution in the ethanol test tube should go cloudy and then a yellow precipitate of tri-iodomethane (iodoform) should be seen. Methanol won’t react.The iodoform test is a specific test for methyl ketones, including acetone. Methanol does not react with the iodoform test. However, ethanol can undergo oxidation to acetaldehyde, which is a methyl ketone, and subsequently react with iodine and sodium hydroxide (NaOH) to produce a yellow precipitate of iodoform. This test can help differentiate between ethanol and methanol.
Why the other options are wrong
- A. The Lucas test is a chemical test that can be used to differentiate between primary, secondary, and tertiary alcohols. It involves the reaction of the alcohol with Lucas reagent (concentrated hydrochloric acid and zinc chloride). Methanol does not react with Lucas reagent, while ethanol reacts slowly, forming a cloudy mixture after several minutes.
- B. The silver mirror test is a specific test for aldehydes. It involves the reaction of an aldehyde with Tollens' reagent (ammoniacal silver nitrate). Methanol and ethanol are not aldehydes, so they do not give a silver mirror when subjected to this test.
- C. Oxidation is a chemical reaction that involves the loss of electrons. Methanol and ethanol can both undergo oxidation. However, the products of oxidation differ. Methanol is oxidized to formaldehyde (methanal), while ethanol is oxidized to acetaldehyde (ethanal) and further to acetic acid (ethanoic acid).
Q147. To produce absolute alcohol (100%) from rectified spirit (95.6% alcohol), the remaining 4.4% water must be removed by a drying agent such as
- A. Calcium oxide✓
- B. Calcium chloride
- C. Calcium carbonate
- D. Carbon monoxide
Explanation: if we add lime (CaO) to the rectified spirit then the water of the mixture can be absorbed by the lime. As a result, the percentage of ethanol will be changed. So the mixture will not act as an azeotropic mixture. In this way, we can prepare absolute alcohol by using the distillation method from a rectified spirit.To remove the remaining water from rectified spirit (95.6% alcohol) and obtain absolute alcohol (100% alcohol), a drying agent is used. The drying agent commonly used for this purpose is calcium oxide (CaO), also known as quicklime.Calcium oxide has a strong affinity for water and can effectively absorb the water present in the rectified spirit. It reacts with water to form calcium hydroxide (Ca(OH)2), releasing heat in the process. The reaction helps to remove the remaining water content, leaving behind pure or absolute alcohol.
Why the other options are wrong
- B. Calcium chloride is a commonly used drying agent for removing water from organic solvents. It has a strong affinity for water and can form hydrates, effectively removing water from the alcohol.
- C. Calcium carbonate, also known as limestone or chalk, is not commonly used as a drying agent for alcohols. While it can absorb small amounts of water, it is not as effective as other drying agents like calcium oxide or calcium chloride.
- D. Carbon monoxide is not a drying agent used for removing water from alcohol. It is a toxic gas and is not suitable for this purpose.
Q148. Which one of the following is also called the silver mirror test?
- A. Fehling’s solution test
- B. Iodoform test
- C. Tollen’s reagent✓
- D. Benedict’s solution test
Explanation: Tollens' reagent is a chemical reagent used to determine the presence of an aldehyde, aromatic aldehyde and alpha-hydroxy ketone functional groups. The reagent consists of a solution of silver nitrate and ammonia. If these functional groups are present you will observe a silver mirror.Fehling's solution tests used to detect the presence of reducing sugars, such as aldehydes or ketones,The iodoform test is used to identify the presence of a methyl ketone, such as acetone, and it involves the formation of a yellow precipitate of iodoform (CHI3).The test that is also called the "silver mirror test" is the Tollen's reagent test.In the Tollen's reagent test, a substance (usually an aldehyde) is mixed with Tollen's reagent, which consists of a solution of silver nitrate (AgNO3) in aqueous ammonia (NH3). The aldehyde reduces the silver ions in Tollen's reagent, resulting in the formation of a silver mirror on the inner surface of the test tube or container. This silver mirror appearance is the basis for the name "silver mirror test."Benedicts solution tests used to detect the presence of reducing sugars, such as aldehydes or ketones.
Why the other options are wrong
- A. Fehling's solution tests used to detect the presence of reducing sugars, such as aldehydes or ketones.
- B. The iodoform test is used to identify the presence of a methyl ketone, such as acetone, and it involves the formation of a yellow precipitate of iodoform (CHI3).
- D. Benedict's solution tests are used to detect the presence of reducing sugars, such as aldehydes or ketones.
Q149. When acetaldehyde reacts with 2,4-dinitrophenylhydrazine (2,4-DNPH), which one of the following products is formed?
- A. Option A
- B. Option B
- C. Option C
- D. Option D✓
Explanation: An aldehyde reacts with 2,4-dinitrophenylhydrazine to give a bright, yellow-to-orange crystalline solid called a 2,4-dinitrophenylhydrazone (2,4-DNP). Acetaldehyde is also known as ethanal (CH3CHO).
Why the other options are wrong
- A. 2,4-dinitrophenylhydrazone is formed during reaction and this is not the formula of 2,4-dinitrophenylhydrazone.
- B. 2,4-dinitrophenylhydrazone is formed during reaction and this is not the formula of 2,4-dinitrophenylhydrazone.
- C. 2,4-dinitrophenylhydrazone is formed during reaction and this is not the formula of 2,4-dinitrophenylhydrazone.
Q150. Both aldehydes and ketones are planar to the neighborhoods of the carbonyl (C=O) group. Which one of the following bonds is distorted towards the oxygen atoms?
- A. π-bond of C and O✓
- B. Sigma bond of C and H
- C. Sigma bond of C and O
- D. Sigma bond of C and C
Explanation: The correct answer is the π-bond of C and O. In a carbonyl group, the π-bond is formed by the overlap of p-orbitals from carbon and oxygen. Due to the higher electronegativity of oxygen compared to carbon, the shared electron density is pulled towards the oxygen atom, resulting in a distortion of the bond. This distortion is significant because it contributes to the reactivity of aldehydes and ketones.In contrast, the sigma bond of C and H does not experience such distortion since hydrogen is less electronegative than carbon, allowing the bond to remain relatively unaffected. The sigma bond of C and O is also part of the carbonyl but is not distorted in the same manner as the π-bond, as it is a single bond. Lastly, the sigma bond of C and C does not involve oxygen and therefore is not relevant to the question of distortion in the carbonyl group.
Why the other options are wrong
- B. This bond does not experience distortion towards oxygen, as hydrogen is less electronegative than carbon and does not significantly influence the carbonyl group's electronic structure.
- C. This bond is part of the carbonyl group but does not experience distortion in the same way as the π-bond due to its nature as a single bond.
- D. This bond is unrelated to the carbonyl group and does not undergo distortion due to the absence of electronegativity differences with respect to oxygen.
Q151. In the following structure, which one is an α-carbon atom?
- A. 1
- B. 2✓
- C. 3
- D. 4
Explanation: Alpha carbon is a carbon atom bonded to a functional group in an organic compound.Carbon 2 is considered to be alpha because it has a functional group attached.
Why the other options are wrong
- A. At carbon 1 no functional group is attached.
- C. At carbon 3 no functional group is attached.
- D. At carbon 4 no functional group is attached.
Q152. The specific substances (metabolite) that fits on the enzyme surface and is converted to products is called
- A. Co-factor
- B. Prosthetic group
- C. Isoenzyme
- D. Substrate✓
Explanation: Substrate binds to the active site on the enzyme surface and is converted into products.Co-factors are non-protein molecules or ions that are required for the proper functioning of certain enzymes. They can assist enzymes in carrying out their catalytic functionsProsthetic groups are non-protein components that are tightly bound to enzymes and are essential for their catalytic activity. They can be considered as specialized co-factors that are permanently attached to the enzyme, assisting in the enzyme's function.Isoenzymes are different forms of an enzyme that catalyze the same reaction but differ in their amino acid sequence, subunit composition, or other properties.In enzyme-catalyzed reactions, the substrate is the specific molecule or metabolite that binds to the active site of the enzyme. The active site is a region on the enzyme's surface that is complementary in shape and chemical properties to the substrate. When the substrate binds to the active site, it undergoes a series of chemical reactions facilitated by the enzyme, leading to the conversion of the substrate into a product.
Why the other options are wrong
- A. Co-factors are non-protein molecules or ions that are required for the proper functioning of certain enzymes. They can assist enzymes in carrying out their catalytic functions.
- B. Prosthetic groups are non-protein components that are tightly bound to enzymes and are essential for their catalytic activity. They can be considered as specialized co-factors that are permanently attached to the enzyme, assisting in the enzyme's function.
- C. Isoenzymes are different forms of an enzyme that catalyze the same reaction but differ in their amino acid sequence, subunit composition, or other properties.
Q153. Polyamide is formed due to the condensation of hexane-dioic acid with
- A. Hexane-1,5-diamine
- B. Hexane-1,6-diamine✓
- C. Hexane-1,4-diamine
- D. Hexane-2,5-diamine
Explanation: Hexane-1,6-diamine – ✅ Correct: Matches perfectly with hexane-dioic acid to form nylon-6,6, a common polyamide.
Why the other options are wrong
- A. Hexane-1,5-diamine – ❌ Incorrect: Has amine groups at positions 1 and 5, causing mismatch in chain length and less optimal polymer formation.
- C. Hexane-1,4-diamine – ❌ Incorrect: Not typically used; shorter spacing disrupts standard polyamide structure.
- D. Hexane-2,5-diamine – ❌ Incorrect: Internal placement of amine groups prevents efficient linear polymerization.
Q154. Haemoglobin is a
- A. Genetic protein
- B. Building protein
- C. Transport protein✓
- D. Structural protein
Explanation: Transport protein: This option is correct. Haemoglobin is a transport protein found in red blood cells. Its main function is to transport oxygen from the lungs to the tissues and carbon dioxide from the tissues back to the lungs. It binds to oxygen in the lungs and releases it in the body's tissues.
Why the other options are wrong
- A. Genetic protein: This option is not correct. Genetic proteins are involved in the storage and transmission of genetic information, such as DNA or RNA. Haemoglobin is not directly involved in genetic processes.
- B. Building protein: This option is also not correct. Building proteins are typically involved in the construction and maintenance of cellular structures, such as collagen in connective tissues. While haemoglobin is important for the body, it does not primarily function as a building protein.
- D. Structural protein: This option is not correct. Structural proteins provide support and structure to cells and tissues. Examples of structural proteins include collagen, keratin, and actin. Haemoglobin does not have a primary role in providing structural support.
Q155. Which one of the following polymer is polystyrene?
- A. Option A✓
- B. Option B
- C. Option C
- D. Option D
Explanation: Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Its formula is (C8H8)n.
Why the other options are wrong
- B. this polymer is not polystyrene.Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Its formula is (C8H8)n.
- C. this polymer is not polystyrene. Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Its formula is (C8H8)n.
- D. this polymer is not polystyrene. Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer known as styrene. Its formula is (C8H8)n.
Q156. Out of these, which nitrogen base is NOT present in DNA?
- A. Adenine
- B. Guanine
- C. Uracil✓
- D. Thymine
Explanation: Uracil: Uracil is not found in DNA. It is a nitrogenous base that is specific to RNA (ribonucleic acid) instead. In RNA, uracil replaces thymine as one of the four bases. Uracil forms a complementary base pair with adenine in RNA.
Why the other options are wrong
- A. Adenine: Adenine is one of the four nitrogenous bases found in DNA. It forms a complementary base pair with thymine (T) through hydrogen bonding. Adenine is always paired with thymine in the DNA double helix.
- B. Guanine: Guanine is also one of the four nitrogenous bases found in DNA. It forms a complementary base pair with cytosine (C) through hydrogen bonding. Guanine is always paired with cytosine in the DNA double helix.
- D. Thymine: Thymine is another nitrogenous base found in DNA. It forms a complementary base pair with adenine (A) through hydrogen bonding. Thymine is always paired with adenine in the DNA double helix.
Q157. Which one of the following is an example of a co-polymer?
- A. Polyamide✓
- B. Polystyrene
- C. Polyvinyl acetate
- D. Polyvinyl chloride
Explanation: Copolymer is a polymer derived from more than one species of monomer.polyamide is the only one that is a copolymer. Polyamide is formed by the condensation polymerization of two different monomers: a diacid and a diamine. Examples of polyamides include Nylon-6,6 (hexamethylenediamine and adipic acid) and Nylon-6 (caprolactam).Polyestrene is a homopolymer derived from the polymerization of a single monomer, styrene.Polyvinyl acetate is also a homopolymer formed from the polymerization of vinyl acetate monomers.Polyvinyl chloride (PVC) is a polymer formed from the polymerization of vinyl chloride monomers.
Why the other options are wrong
- B. Polyestrene is a homopolymer derived from the polymerization of a single monomer, styrene.
- C. Polyvinyl acetate is also a homopolymer formed from the polymerization of vinyl acetate monomers.
- D. Polyvinyl chloride (PVC) is a polymer formed from the polymerization of vinyl chloride monomers.
Q158. The biggest source of acid rain is the oxide of:
- A. N
- B. S✓
- C. O
- D. C
Explanation: Acid rain results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents.The biggest source of acid rain is the oxide of sulfur (S).Acid rain is formed when sulfur dioxide (SO2) and nitrogen oxides (NOx), primarily nitrogen (NO2), are released into the atmosphere as pollutants from various human activities, particularly the combustion of fossil fuels. These pollutants can undergo chemical reactions in the atmosphere and sulfuric acid (H2SO4) and nitric acid (HNO3), respectively. These acids can then combine with water vapor in the atmosphere and fall to the ground as acid rain.
Why the other options are wrong
- A. N (Nitrogen): Nitrogen oxide (NOx) emissions, primarily from human activities such as fossil fuel combustion, contribute to acid rain. However, nitrogen oxide emissions are not the biggest source of acid rain.
- C. O (Oxygen): Oxygen is not directly responsible for the formation of acid rain. While oxygen is present in the atmosphere and plays a role in various chemical reactions, it is not the primary source of acidity in rainwater.
- D. C (Carbon): Carbon dioxide (CO2) emissions, a byproduct of fossil fuel combustion, contribute to climate change but are not a direct cause of acid rain.
Q159. Burning of which one of the following waste is considered as useful industrial fuel or to produce electricity:
- A. Metals
- B. Grass
- C. Paper
- D. Plastic✓
Explanation: Burning plastic waste releases a high amount of energy, making it useful as an industrial fuel or for electricity generation, whereas grass has much lower energy content and is not commonly used for such purposes.
Why the other options are wrong
- A. Metals: Burning metals as a waste is not considered a useful industrial fuel or a common method to produce electricity. While some metals can be used as fuel sources in specific industrial processes (e.g., in metal smelting), it is not a widespread practice.
- B. Burning plastic waste releases a high amount of energy, making it useful as an industrial fuel or for electricity generation, whereas grass has much lower energy content and is not commonly used for such purposes.
- C. Paper: Burning paper waste can also be used as a fuel source in certain contexts. Paper can be transformed into a form of biomass fuel, such as pellets or briquettes, which can be burned to generate heat or electricity. However, the recycling and reuse of paper waste are generally preferred over burning it for energy.
Q160. Which of the following is the correct dot and cross diagram of bonding between two chlorine atoms?
- A. Option A
- B. Option B
- C. Option C✓
- D. Option D
Explanation: Two chlorine atoms will form a covalent bond between shared electrons. Covalent bonds occur between non-metals.
Why the other options are wrong
- A. This is not a correct option. Two chlorine atoms will form a covalent bond between shared electrons. Covalent bonds occur between non-metals.
- B. This is not a correct option. Two chlorine atoms will form a covalent bond between shared electrons. Covalent bonds occur between non-metals.
- D. This is not a correct option. Two chlorine atoms will form a covalent bond between shared electrons. Covalent bonds occur between non-metals.
Q161. The equation that represents standard enthalpy of atomization of hydrogen is:
- A. Option A
- B. Option B
- C. Option C✓
- D. Option D
Explanation: Standard enthalpy of atomization is the enthalpy change that occurs when one mole of a sample is dissociated into its atoms under standard conditions. All bonds in the compound are broken in atomization and none are formed, so enthalpies of atomization are always positive (endothermic). For example, the standard enthalpy of atomization of hydrogen is given below.
Why the other options are wrong
- A. This represents not a standard enthalpy of atomization of hydrogen.
- B. This represents not a standard enthalpy of atomization of hydrogen.
- D. This represents not a standard enthalpy of atomization of hydrogen.
Q162. Standard enthalpy of combustion of graphite at 25 °C is –393.51 kJ mol-1 and that of diamond is –395.41 kJ mol-1. The enthalpy change for graphite is:
- A. -1.91✓
- B. +2.1
- C. -2.1
- D. +1.91
Explanation: -2.1: This option suggests a negative value for the enthalpy change of graphite, and it is the correct answer. Since the standard enthalpy of combustion of graphite is -393.51 kJ mol-1 and that of diamond is -395.41 kJ mol-1, the enthalpy change for graphite can be calculated as the difference between these two values:Enthalpy change for graphite = Standard enthalpy of combustion of diamond - Standard enthalpy of combustion of graphite= (-395.41 kJ mol-1) - (-393.51 kJ mol-1)= -1.90 kJ mol-1Rounding off to two decimal places, the enthalpy change for graphite is approximately -1.91 kJ mol-1.
Why the other options are wrong
- B. +2.1: This option suggests a positive value for the enthalpy change of graphite. However, based on the given information, the enthalpy change for graphite should be negative, as it is less than the standard enthalpy of combustion of diamond. Therefore, this option is incorrect.
- C. -2.1: This option suggests a negative value for the enthalpy change of graphite, and it is the correct answer. Since the standard enthalpy of combustion of graphite is -393.51 kJ mol-1 and that of diamond is -395.41 kJ mol-1, the enthalpy change for graphite can be calculated as the difference between these two values:Enthalpy change for graphite = Standard enthalpy of combustion of diamond - Standard enthalpy of combustion of graphite= (-395.41 kJ mol-1) - (-393.51 kJ mol-1)= -1.90 kJ mol-1Rounding off to two decimal places, the enthalpy change for graphite is approximately -1.91 kJ mol-1.
- D. +1.91: This option suggests a positive value for the enthalpy change of graphite, which is inconsistent with the given information. Therefore, this option is incorrect.
Q163. 10.0 grams of glucose are dissolved in water to make 100 cm3 of its solution, its molarity is:
- A. 0.55✓
- B. 0.1
- C. 10
- D. 1
Explanation: 0.55: This option suggests a molarity of 0.55 for the glucose solution. To determine the molarity, we need to calculate the number of moles of glucose present in the solution. Given that the mass of glucose is 10.0 grams and its molar mass is approximately 180.16 g/mol, we can calculate the number of moles using the formula:Number of moles = Mass of substance / Molar massNumber of moles of glucose = 10.0 g / 180.16 g/mol ≈ 0.0554 molNow, we can calculate the molarity using the formula:Molarity = Number of moles / Volume of solution (in liters)Since the volume of the solution is given as 100 cm3, we need to convert it to liters:Volume of solution = 100 cm3 / 1000 = 0.1 LMolarity = 0.0554 mol / 0.1 L ≈ 0.554 M
Why the other options are wrong
- B. 0.1: This option suggests a molarity of 0.1 for the glucose solution. However, the calculated molarity in option a) is approximately 0.554 M, which is not equal to 0.1 M. Therefore, this option is incorrect.
- C. 10: This option suggests a molarity of 10 for the glucose solution. Since molarity is the number of moles of solute per liter of solution, a molarity of 10 would mean that the number of moles of glucose is 10 times the volume of the solution, which is not possible. Therefore, this option is incorrect.
- D. 1: This option suggests a molarity of 1 for the glucose solution. However, the calculated molarity in option a) is approximately 0.554 M, which is not equal to 1 M. Therefore, this option is incorrect.
Q164. Given solution contains 16.0 g of CH3OH, 92.0 g of C2H5OH and 36 g of water. Which statement about mole fraction of the components is true?
- A. Mole fraction of CH3OH is highest among all components
- B. Mole fraction of C2H5OH and H2O is the same✓
- C. Mole fraction of CH3OH and C2H5OH is same
- D. Mole fraction of H2O is the lowest among all
Explanation: No. of moles of CH3OH = 16/32 = 0.5No. of moles of C2H5OH= 92/46 =2No. of moles of H2O = 36/18 =2Formula to calculate mole fraction,no. of moles of the component/ Total no. of moles of all the components∴ no. of moles of CH3OH = 0.5/4.5 =1/9no. of moles of C2H5OH= 2/4.5no. of moles of H2O = 2/4.5
Why the other options are wrong
- A. Mole fraction of CH3OH is not the highest among all components: Mole fraction is calculated by dividing the number of moles of a component by the total number of moles of all components in the solution. It is incorrect.
- C. Mole fraction of CH3OH and C2H5OH is the same: From the calculations, we can see that the mole fraction of CH3OH is approximately 0.124, while the mole fraction of C2H5OH is approximately 0.498. Therefore, option c) is incorrect.
- D. Mole fraction of H2O is not the lowest among all: From the calculations, we can see that the mole fractions of C2H5OH and H2O are both approximately 0.498, while the mole fraction of CH3OH is approximately 0.124. Therefore, option d) is incorrect.
Q165. Study the following facts:Zn → Zn+2 + 2e― Eo = +0.76 VCu → Cu+2 + 2e― Eo = – 0.34 V
- A. Cu + Zn+2 → Cu+2 + Zn
- B. Cu+2 + Zn+2 → Cu + Zn
- C. Cu+2 + Zn → Cu + Zn+2✓
- D. Cu+2 + Zn+2 → Cu + Zn+2
Explanation: The half cell equation with the lower Eo is the anode. Electrons travel from cathode to anode. (Flip the equation with the lower Eo and then 2e cancel out).the correct redox reaction involving Cu and Zn is: Cu+2 + Zn -> Cu + Zn+2Cu+2 + Zn -> Cu + Zn+2: This equation represents a redox reaction between copper ions (Cu2+) metal (Zn). In this reaction, copper ions gain two electrons to form copper metal, while zinc atoms two electrons to form zinc ions. This reaction is a spontaneous redox reaction because the potential of copper ions (Cu2+) is lower than that of zinc ions (Zn2+). Therefore, copper ions reduced, and zinc metal is oxidized.
Why the other options are wrong
- A. the correct redox reaction involving Cu and Zn is: Cu+2 + Zn -> Cu + Zn+2Cu+2 + Zn -> Cu + Zn+2: This equation represents a redox reaction between copper ions (Cu2+) and zinc metal (Zn). In this reaction, copper ions gain two electrons to form copper metal, while zinc atoms lose two electrons to form zinc ions. This reaction is a spontaneous redox reaction because the reduction potential of copper ions (Cu2+) is lower than that of zinc ions (Zn2+). Therefore, copper ions are reduced, and zinc metal is oxidized.
- B. the correct redox reaction involving Cu and Zn is: Cu+2 + Zn -> Cu + Zn+2Cu+2 + Zn -> Cu + Zn+2: This equation represents a redox reaction between copper ions (Cu2+) and zinc metal (Zn). In this reaction, copper ions gain two electrons to form copper metal, while zinc atoms lose two electrons to form zinc ions. This reaction is a spontaneous redox reaction because the reduction potential of copper ions (Cu2+) is lower than that of zinc ions (Zn2+). Therefore, copper ions are reduced, and zinc metal is oxidized.
- D. the correct redox reaction involving Cu and Zn is: Cu+2 + Zn -> Cu + Zn+2Cu+2 + Zn -> Cu + Zn+2: This equation represents a redox reaction between copper ions (Cu2+) and zinc metal (Zn). In this reaction, copper ions gain two electrons to form copper metal, while zinc atoms lose two electrons to form zinc ions. This reaction is a spontaneous redox reaction because the reduction potential of copper ions (Cu2+) is lower than that of zinc ions (Zn2+). Therefore, copper ions are reduced, and zinc metal is oxidized.
Q166. Keeping in mind the electrode potential, which one of the following reactions is feasible?
- A. Zn+2 + Cu → Cu+2 + Zn
- B. Zn + MgSO4 → ZnSO4 + Mg
- C. Fe + CuSO4 → FeSO4 + Cu✓
- D. Cd + MgSO4 → CdSO4 + Mg
Explanation: Fe + CuSO₄ → FeSO₄ + Cu is feasible because iron has a lower reduction potential (–0.44 V) than copper (+0.34 V), meaning iron is more reactive and can displace copper from its salt solution. The positive cell potential (+0.78 V) confirms the reaction is spontaneous.
Why the other options are wrong
- A. Zn²⁺ + Cu → Cu²⁺ + Zn is not feasible because copper has a higher reduction potential (+0.34 V) than zinc (–0.76 V).That means Cu cannot reduce Zn²⁺ — zinc is actually the stronger reducing agent, so the reaction would go in the reverse direction instead.
- B. Zn + MgSO4 → ZnSO4 + Mg: This reaction involves the transfer of electrons from Zn to Mg. The standard electrode potential for Zn is -0.76 V, and for Mg is -2.37 V. Since the electrode potential of Zn is higher than Mg, the reaction is not feasible. Therefore, option b) is not feasible.
- D. Cd + MgSO4 → CdSO4 + Mg: This reaction involves the transfer of electrons from Cd to Mg. The standard electrode potential for Cd is -0.40 V, and for Mg is -2.37 V. Since the electrode potential of Cd is higher than Mg, the reaction is not feasible. Therefore, option d) is not feasible.
Q167. What is the correct relation between pH and pKa?
- A. pH = pKa + log[ Acid/Base ]
- B. pH = pKa - log[ Acid/Base ]✓
- C. pH = pKa - log[ Base/Acid ]
- D. pH = pKa + log[ Base]
Explanation: The Henderson-Hasselbalch equation relates pKa and pH. However, it is only an approximation and should not be used for concentrated solutions or for extremely low pH acids or high pH bases.pH = pKa + log ([conjugate base]/[weak acid])pH = pka + log ([A-] / [HA])pH is equal to the sum of the pKa value and the log of the conjugate base concentration divided by the weak acid concentration.
Why the other options are wrong
- A. pH = pKa + log[ Acid/Base ]: This equation is the Henderson-Hasselbalch equation, which relates the pH of a solution to the pKa of the acid and the ratio of the concentrations of the acid and its conjugate base. The pKa represents the negative logarithm of the acid dissociation constant (Ka). The correct relation should be pH = pKa - log[ Acid/Base ], so option a) is not correct.
- C. pH = pKa - log[ Base/Acid ]: This equation has the logarithm term reversed compared to the correct relation. The ratio of the base to the acid should be in the numerator, not the denominator. Therefore, option c) is not correct.
- D. pH = pKa + log[ Base/Acid ]: This equation has the logarithm term reversed compared to the correct relation. The ratio of the base to the acid should be in the denominator, not the numerator. Therefore, option d) is not correct.
Q168. Which one of the following is the correct presentation for Ksp?
- A. Option A
- B. Option B✓
- C. Option C
- D. Option D
Explanation: The solubility product constant, Ksp , is the equilibrium constant for a solid substance dissolving in an aqueous solution. It represents the level at which a solute dissolves in solution. The more soluble a substance is, the higher the Ksp value it has.
Why the other options are wrong
- A. This is not the correct presentation for Ksp.
- C. This is not the correct presentation for Ksp.
- D. This is not the correct presentation for Ksp.
Q169. The weight of an electron is:
- A. 9.108 × 10−30g
- B. 9.108 × 10−25 g
- C. 9.108 × 10−31 g✓
- D. Too less to be measured
Explanation: 9.108 × 10-30 g: This option represents the approximate weight of an electron. It is in the range of the actual mass of an electron, which is approximately 9.109 × 10-30 kg.
Why the other options are wrong
- A. Electrons are negatively charged particles weighing zero atomic mass units and located in the various orbitals of the energy levels outside the atomic nucleus. The electron actually weighs 9.11x10-30 grams. This means it would take about 1,830 electrons to equal the mass of one proton.
- B. 9.108 × 10−25 g: This option also represents a weight that is too heavy for an electron. Again, the actual weight of an electron is much smaller.
- D. Electrons are negatively charged particles weighing zero atomic mass units and located in the various orbitals of the energy levels outside the atomic nucleus. The electron actually weighs 9.11x10-28 grams. This means it would take about 1,830 electrons to equal the mass of one proton.
Q170. One method of creating an inverted population is known as _ and consists of illuminating the laser material with light.
- A. Optical Pumping✓
- B. Excitation
- C. Bremsstrahlung
- D. Holography
Explanation: Optical pumping suggests that the method of creating an inverted population is called optical pumping. Optical pumping is a technique where the laser material is illuminated with light to excite the atoms or molecules, causing them to populate higher energy levels. This population inversion is necessary for the operation of a laser.
Why the other options are wrong
- B. This option suggests that the method of creating an inverted population is called excitation. Excitation refers to the process of promoting an atom or molecule from a lower energy state to a higher energy state. While excitation is involved in the process of creating an inverted population, it is not the specific method or technique used.
- C. This option refers to a different phenomenon unrelated to creating an inverted population. Bremsstrahlung is the emission of electromagnetic radiation (usually X-rays or gamma rays) when a charged particle, such as an electron, is decelerated or deflected by another charged particle or a nucleus.
- D. This option refers to a different technique used for creating three-dimensional images called holograms. Holography involves the use of interference patterns recorded on photographic plates or other media to reconstruct a three-dimensional image when illuminated with coherent light.
Q171. In population inversion (Ruby Laser) atoms can reside in the excited state for:
- A. 10-11
- B. 10-8
- C. 10-3✓
- D. 10+3
Explanation: In the context of population inversion in a Ruby laser, the correct answer is that atoms can reside in the excited state for a relatively long time, typically in the order of 10^-3 seconds (or 1 millisecond).
Why the other options are wrong
- A. In the context of population inversion in a Ruby laser, the correct answer is that atoms can reside in the excited state for a relatively long time, typically in the order of 10^-3 seconds (or 1 millisecond). Hence this option is incorrect.
- B. In the context of population inversion in a Ruby laser, the correct answer is that atoms can reside in the excited state for a relatively long time, typically in the order of 10^-3 seconds (or 1 millisecond). Hence this option is incorrect.
- D. In the context of population inversion in a Ruby laser, the correct answer is that atoms can reside in the excited state for a relatively long time, typically in the order of 10^-3 seconds (or 1 millisecond). Hence this option is incorrect.
Q172. If electrons of charge ‘e’, with rest mass ‘m’, are accelerated through a potential difference ‘V’ and strike a metal target, then velocity of electrons is:
- A. Ve/m
- B. √(Ve/m)
- C. √(Ve/)2m
- D. √(2Ve/m)✓
Explanation: √(2Ve/m): This option suggests that the velocity of electrons is the square root of twice the potential difference (2V) divided by the rest mass (m). This option introduces a factor of 2 in the numerator, which is incorrect based on the equation for velocity.Based on the correct equation, the velocity of electrons accelerated through a potential difference (V) can be calculated using the formula:velocity = √(2eV/m)Therefore, the correct answer is option d) √(2Ve/m).Please note that 'e' represents the charge of an electron, 'm' represents the rest mass of an electron, and 'V' represents the potential diffe√(2Ve/m): This option suggests that the velocity of electrons is the square root of twice the potential difference (2V) divided by the rest mass (m). This option introduces a factor of 2 in the numerator, which is incorrect based on the equation for velocity.Based on the correct equation, the velocity of electrons accelerated through a potential difference (V) can be calculated using the formula:velocity = √(2eV/m)Therefore, the correct answer is option d) √(2Ve/m).Please note that 'e' represents the charge of an electron, 'm' represents the rest mass of an electron, and 'V' represents the potential difference.
Why the other options are wrong
- A. Ve/m: This option suggests that the velocity of electrons is directly proportional to the potential difference (V) and inversely proportional to the rest mass (m). However, this option does not account for the square root relationship between velocity and potential difference, so it is not the correct answer.
- B. √(Ve/m): This option suggests that the velocity of electrons is the square root of the potential difference (V) divided by the rest mass (m). This option correctly incorporates the square root relationship between velocity and potential difference, so it is a valid choice.
- C. √(Ve/2m): This option suggests that the velocity of electrons is the square root of the potential difference (V) divided by twice the rest mass (2m). This option introduces a factor of 2 in the denominator, which is incorrect based on the equation for velocity.
Q173. In X-ray tube, electrons after being accelerated through velocity ‘v’ strike the target, then the wavelength of emitted X-rays is:
- A. Not greater than hc/eV
- B. . Not less than hc/eV
- C. Equal to the h/mV
- D. Greater than or equal to hc/eV✓
Explanation: Greater than or equal to hc/eV: This option suggests that the wavelength of emitted X-rays is at least equal to the value of hc/eV. This option is correct because the wavelength of X-rays emitted from the X-ray tube is directly related to the energy of the X-rays, which is determined by the accelerating voltage.Based on the correct understanding of X-ray emission in an X-ray tube, the correct answer is option d) Greater than or equal to hc/eV.Please note that 'h' represents Planck's constant, 'c' represents the speed of light, 'e' represents the electron charge, 'V' represents the accelerating voltage, and 'm' represents the electron mass.
Why the other options are wrong
- A. Not greater than hc/eV: This option suggests that the wavelength of emitted X-rays is limited and cannot exceed the value of Planck's constant (h) times the speed of light (c) divided by the product of the electron charge (e) and the accelerating voltage (V). This option implies that the wavelength cannot be longer than hc/eV, which is a valid statement.
- B. Not less than hc/eV: This option suggests that the wavelength of emitted X-rays is limited and cannot be shorter than the value of hc/eV. This option is incorrect because the wavelength can indeed be shorter than hc/eV depending on the energy levels involved in the X-ray emission process.
- C. Equal to h/mV: This option suggests that the wavelength of emitted X-rays is directly proportional to Planck's constant (h) divided by the product of the electron mass (m) and the electron velocity (V). This option is incorrect because the velocity of electrons is not directly related to the wavelength of X-rays emitted from the X-ray tube.
Q174. In the reaction, 234Th92 → 234Y91 + 0e-1, the electron 0e-1 emits from the:
- A. Z – 6, A – 12
- B. Z – 2, A – 4
- C. Z + 1, A✓
- D. Z + 3, A
Explanation: Z + 1, A: This option suggests that the electron is emitted from the electron cloud, resulting in a change in the atomic number (Z) but no change in the mass number (A) of the nucleus. This option is correct because the emission of an electron does not affect the number of protons and neutrons in the nucleus.
Why the other options are wrong
- A. Z – 6, A – 12: This option suggests that the electron is emitted from the nucleus of the atom, resulting in a change in both the atomic number (Z) and the mass number (A) of the nucleus. However, in nuclear reactions, electrons are not emitted from the nucleus itself but are instead emitted from the electron cloud surrounding the nucleus. Therefore, this option is incorrect.
- B. Z – 2, A – 4: This option suggests that the electron is emitted from the nucleus, resulting in a change in both the atomic number (Z) and the mass number (A) of the nucleus. As explained earlier, electrons are not emitted from the nucleus in nuclear reactions, so this option is also incorrect.
- D. Z + 3, A: This option suggests a significant change in both the atomic number (Z) and the mass number (A) of the nucleus. However, the emission of an electron does not result in such a drastic change in the nucleus. Therefore, this option is incorrect.
Q175. A certain radioactive nuclide of mass number ‘x’ decays by β-emission and α-emission to a second nuclide of mass number ‘t’. Which of the following correctly relates ‘x’ and ‘t’?
- A. x = t + 4✓
- B. x = t – 4
- C. x – 3 = t
- D. x – 1 = t
Explanation: x-4 = tx = t + 4x = t + 4: This option suggests that the initial nuclide with mass number 'x' decays by β-emission and α-emission, resulting in a final nuclide with mass number 't' that is four units less than the initial nuclide. This option is correct because α-emission results in the loss of an α particle, which has a mass number of 4. Therefore, the mass number of the final nuclide would be four units less than the initial nuclide.
Why the other options are wrong
- B. x = t - 4: This option suggests that the initial nuclide with mass number 'x' decays by β-emission and α-emission, resulting in a final nuclide with mass number 't' that is four units greater than the initial nuclide. This option is incorrect because α-emission results in the loss of an α particle, which has a mass number of 4. Therefore, the mass number of the final nuclide would be four units less than the initial nuclide.
- C. x - 3 = t: This option suggests that the initial nuclide with mass number 'x' decays by β-emission and α-emission, resulting in a final nuclide with mass number 't' that is three units less than the initial nuclide. This option is incorrect as it does not accurately represent the typical changes in mass number during β and α decay.
- D. x - 1 = t: This option suggests that the initial nuclide with mass number 'x' decays by β-emission and α-emission, resulting in a final nuclide with mass number 't' that is one unit less than the initial nuclide. This option is incorrect because α-emission typically results in the loss of an α particle, which has a mass number of 4. Therefore, the mass number of the final nuclide would be four units less than the initial nuclide.
Q176. During the decay of radioactive isotopes 232X90 to a stable isotope, six α-particles and four β - particles are emitted, what is the atomic number ‘Z’ and mass number ‘A’ of the stable isotopes?
- A. Z = 70, A = 220
- B. Z = 78, A = 212
- C. Z = 82, A = 212
- D. Z = 82, A = 208✓
Explanation: Z = 82, A = 208: This option suggests that during the decay of the radioactive isotope 232 90X, six α-particles and four β-particles are emitted, resulting in a stable isotope with atomic number (Z) of 82 and mass number (A) of 208. This option is correct as it accurately represents the resulting stable isotopes from the given decay process.
Why the other options are wrong
- A. Z = 70, A = 220: This option suggests that during the decay of the radioactive isotope 232 90X, six α-particles and four β-particles are emitted, resulting in a stable isotope with atomic number (Z) of 70 and mass number (A) of 220. However, this option is incorrect as the stable isotopes resulting from the given decay process do not match the values provided.
- B. Z = 78, A = 212: This option suggests that during the decay of the radioactive isotope 232 90X, six α-particles and four β-particles are emitted, resulting in a stable isotope with atomic number (Z) of 78 and mass number (A) of 212. This option is incorrect as it does not accurately represent the resulting stable isotopes from the given decay process.
- C. Z = 82, A = 212: This option suggests that during the decay of the radioactive isotope 232 90X, six α-particles and four β-particles are emitted, resulting in a stable isotope with atomic number (Z) of 82 and mass number (A) of 212. This option is incorrect as it does not accurately represent the resulting stable isotopes from the given decay process.
Q177. Cobalt 60 is used in medicine and is an intense source of:
- A. α-particles
- B. β-particles
- C. γ-rays✓
- D. Neutrons
Explanation: γ-rays: γ-rays are high-energy photons emitted during radioactive decay or nuclear reactions. They have no charge and are similar to X-rays but with higher energy. Cobalt-60 is an intense source of γ-rays. It is commonly used in medicine for radiation therapy and imaging.
Why the other options are wrong
- A. α-particles: α-particles are helium nuclei consisting of two protons and two neutrons. They have a positive charge and are relatively large and heavy. Cobalt-60 is not a source of α-particles.
- B. β-particles: β-particles are high-energy electrons or positrons emitted during certain radioactive decays. They have a negative charge and are much smaller and lighter than α-particles. Cobalt-60 does not emit β-particles.
- D. Neutrons: Neutrons are subatomic particles with no charge and a mass similar to that of a proton. They are not emitted by Cobalt-60.
Q178. In fluid flow, for the equation of continuity A1v1 = A2v2. If the velocity of the fluid at one end is doubled, then what will be the cross-sectional area at this end?
- A. Double
- B. Half✓
- C. (Half)2
- D. (Double)2
Explanation: Half: This is the correct answer. According to the equation of continuity (A1v1 = A2v2), if the velocity of the fluid at one end is doubled, the cross-sectional area at that end will be halved to maintain the constant product.
Why the other options are wrong
- A. Double: If the velocity of the fluid at one end is doubled, according to the equation of continuity (A1v1 = A2v2), the product of the cross-sectional area and velocity should remain constant. Therefore, if the velocity is doubled, the cross-sectional area at that end should be halved (not doubled).
- C. (Half)2: Squaring the value of half does not result in the correct relationship. The area should be halved, not squared.
- D. (Double)2: Squaring the value of double does not result in the correct relationship. The area should be halved, not squared.
Q179. The value of least distance vision for a normal eye is:
- A. 20 cm
- B. 30cm
- C. 25cm✓
- D. 40cm
Explanation: This option suggests that the least distance of distinct vision for a normal eye is 25 cm. This is the correct value. The least distance of distinct vision refers to the minimum distance at which the human eye can focus on an object and see it clearly without any strain.
Why the other options are wrong
- A. This option suggests that the least distance of distinct vision for a normal eye is 20 cm. However, this is not the correct value.
- B. This option suggests that the least distance of distinct vision for a normal eye is 30 cm. However, this is not the correct value.
- D. This option suggests that the least distance of distinct vision for a normal eye is 40 cm. However, this is not the correct value.
Q180. The distance between two dark adjacent fringes is mathematically written as:
- A. ∆Y = λL/d✓
- B. ∆Y = λ/dL
- C. ∆Y = λd/L
- D. ∆Y = d/λL
Explanation: This option represents the mathematical expression for the distance between two dark adjacent fringes. It states that the fringe spacing (∆Y) is equal to the product of the wavelength of light (λ), the distance from the source to the screen (L), divided by the separation between the slits (d). This is the correct mathematical representation for the fringe spacing in interference patterns.
Why the other options are wrong
- B. This option is not the correct mathematical expression for the distance between two dark adjacent fringes. The numerator and denominator are reversed, which would lead to an incorrect calculation.
- C. This option is not the correct mathematical expression for the distance between two dark adjacent fringes. The division is performed between the separation between the slits (d) and the distance from the source to the screen (L), which would lead to an incorrect result.
- D. This option is not the correct mathematical expression for the distance between two dark adjacent fringes. The numerator and denominator are reversed, and there is an additional division by the wavelength (λ), which would give an incorrect value for the fringe spacing.
Q181. In Young’s Double Slit Experiment, slit separation x = 0.05 cm, the distance between screen and slit D = 200 cm, fringes separation x = 0.13 cm, then the wavelength ‘λ’ of light is:
- A. λ = 1.23 x 10-2 m
- B. λ = 3.25 x 10-4 m✓
- C. λ = 4.55 x 10-5 m
- D. λ = 5.1 x 10-7 m
Explanation: In Young’s Double Slit Experiment, the fringe separation (β) is given by:β=λD/xGiven:β=0.13 cm=0.0013 mx=0.05 cm=0.0005 mD=200 cm=2 mλ=0.0013×0.0005/2=3.25×10−7 m
Why the other options are wrong
- A. This option is not the correct value for the wavelength of light in Young's Double Slit Experiment. The given value is relatively large, and it does not match the typical range of visible light wavelengths.
- C. This option is not the correct value for the wavelength of light in Young's Double Slit Experiment. The given value is relatively large, and it does not match the typical range of visible light wavelengths.
- D. . This option is incorrect as per explanations and calculations .
Q182. In the normal adjustment of a compound microscope, the eyepiece is positioned so that the final image is formed at
- A. Optical Center
- B. Infinity✓
- C. Principle Focus
- D. Near Point
Explanation: This option is the correct position for the final image in the normal adjustment of a compound microscope. In the normal adjustment, the eye piece of the microscope is positioned in such a way that the final image formed by the objective lens is at infinity. This allows the viewer to observe the image comfortably and clearly.
Why the other options are wrong
- A. This option is not the correct position for the final image in the normal adjustment of a compound microscope. The optical center refers to the central point of an optical element, such as a lens, and it does not determine the position of the final image in a microscope.
- C. This option is not the correct position for the final image in the normal adjustment of a compound microscope. The principle focus refers to the focal point of a lens or mirror, and it does not determine the position of the final image in a microscope.
- D. This option is not the correct position for the final image in the normal adjustment of a compound microscope. The near point refers to the closest distance at which an individual can see objects clearly without any visual aid, and it is not directly related to the position of the final image in a microscope.
Q183. When two slightly different frequency waves superimpose _ is formed.
- A. Stationary waves
- B. Sounds waves
- C. Beats✓
- D. Light waves
Explanation: When two sound waves of different frequency approach your ear, the alternating constructive and destructive interference causes the sound to be alternatively soft and loud - a phenomenon which is called "beating" or producing beats.When two slightly different frequency waves superimpose, beats are formed. Beats occur when two waves with slightly different frequencies interfere with each other. The resulting pattern consists of alternating regions of constructive and destructive interference, resulting in a periodic variation in the amplitude (loudness) of the combined wave.Stationary waves, also known as standing waves, are formed when two waves of the same frequency and amplitude traveling in opposite directions superimpose.Sound waves are longitudinal waves that result from the mechanical vibrations of particles in a medium, such as air or water.Beats occur when two waves with slightly different frequencies interfere with each other.Light waves are electromagnetic waves that consist of oscillating electric and magnetic fields.
Why the other options are wrong
- A. Stationary waves, also known as standing waves, are formed when two waves of the same frequency and amplitude traveling in opposite directions superimpose.
- B. Sound waves are longitudinal waves that result from the mechanical vibrations of particles in a medium, such as air or water.
- D. Light waves are electromagnetic waves that consist of oscillating electric and magnetic fields.
Q184. A body is having weight 20 N, when the elevator is descended with a = 0.1 ms-2, then the value of tension ‘T’ is:
- A. 196 N
- B. 19.8 N✓
- C. 1.98 N
- D. 2 N
Explanation: 19.8 N: This option is the correct value for the tension 'T' when the elevator is descended with an acceleration of 0.1 m/s². The tension in the cable can be calculated using the equation T = mg - ma, where 'm' is the mass of the body, 'g' is the acceleration due to gravity, and 'a' is the acceleration of the elevator. Substituting the given values, T = (20 N) - (0.1 m/s²) = 19.8 N.
Why the other options are wrong
- A. 196 N: This option is not the correct value for the tension 'T' when the elevator is descended with an acceleration of 0.1 m/s². The weight of the body is given as 20 N, which represents the force exerted by gravity. The tension 'T' in the elevator cable will be less than the weight of the body due to the opposing force provided by the acceleration of the elevator.
- C. 1.98 N: This option is not the correct value for the tension 'T' in this scenario. It is much smaller than the weight of the body and does not account for the acceleration of the elevator.
- D. 2 N: This option is not the correct value for the tension 'T' when the elevator is descended with an acceleration of 0.1 m/s². It is smaller than the weight of the body but does not account for the acceleration of the elevator.
Q185. Sodium 24 has a half-life of 15 hours and it is used in medicine to estimate:
- A. Kidney Function
- B. Plasma Blood Volume✓
- C. Iron in Plasma
- D. Thyroid Function
Explanation: The sodium-24 isotope is used to study the circulation of blood. Sodium-24 (Na-24) IS commonly used in medicine for estimating plasma blood volume.
Why the other options are wrong
- A. Kidney Function: Sodium-24 (Na-24) is not typically used to estimate kidney function. Kidney function is usually assessed using other methods such as blood tests, imaging techniques, or urine analysis.
- C. Iron in Plasma: Sodium-24 is not used to estimate iron levels in plasma. Iron levels in the blood are typically measured using specific iron tests or blood tests such as serum ferritin, transferrin saturation, or total iron-binding capacity.
- D. Thyroid Function: Sodium-24 is not used to estimate thyroid function. Thyroid function is typically assessed using specific thyroid function tests such as measuring levels of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and triiodothyronine (T3).
Q186. The unit of temperature in base unit is:
- A. Celsius
- B. Degree
- C. Kelvin✓
- D. Fahrenheit
Explanation: Kelvin: Kelvin (K) is the base unit of temperature in the International System of Units (SI). It is an absolute temperature scale where 0 Kelvin represents absolute zero, the theoretical lowest possible temperature where all molecular motion ceases. Kelvin is commonly used in scientific and technical applications, particularly in physics and chemistry.
Why the other options are wrong
- A. Celsius: Celsius (°C) is a unit of temperature commonly used in everyday life and scientific measurements. It is based on the Celsius scale, where 0°C represents the freezing point of water and 100°C represents the boiling point of water at standard atmospheric pressure. However, Celsius is not considered a base unit of temperature in the International System of Units (SI).
- B. Degree: The term "degree" by itself is not a specific unit of temperature. It is often used as a modifier along with a specific temperature scale, such as degrees Celsius (°C) or degrees Fahrenheit (°F), to indicate the unit of measurement.
- D. Fahrenheit: Fahrenheit (°F) is a temperature scale commonly used in the United States and a few other countries. It is based on the Fahrenheit scale, where 32°F represents the freezing point of water and 212°F represents the boiling point of water at standard atmospheric pressure. Fahrenheit is not considered a base unit of temperature in the International System of Units (SI).
Q187. The dimensions of pressure is:
- A. A
- B. B
- C. C
- D. D✓
Explanation: The following is the solution:𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 = 𝐹𝑜𝑟𝑐𝑒/𝐴𝑟𝑒𝑎By dimensional analysis: 𝑃𝑟𝑒𝑠𝑠𝑢𝑟𝑒 = 𝑘𝑔. 𝑚. 𝑠−2/𝑚2 Therefore, by simplification we get out answer:[MLT−2]/[L2]=ML-1T-2The correct dimension of pressure: [MLT−2]/[L2]=ML-1T-2
Why the other options are wrong
- A. Incorrect as per the formula
- B. Incorrect as per the formula
- C. Incorrect as per the formula
Q188. Mass flow per second of the fluid is given by:
- A. ρAv✓
- B. Av
- C. ρv
- D. Av/ρ
Explanation: 𝑀𝑎𝑠𝑠/𝑡𝑖𝑚𝑒 = ρ × 𝑉/𝑇 = ρ × 𝐴 × 𝑑/𝑇 = ρ × 𝐴 × 𝑣Where T is time, V is volume, A is area, v is velocity.Mass flow per second of fluid is given by: pAv
Why the other options are wrong
- B. Av: This option represents the volumetric flow rate of a fluid. Here, A represents the cross-sectional area through which the fluid is flowing, and v represents the velocity of the fluid. Multiplying the cross-sectional area and velocity gives you the volume flow per second of the fluid.
- C. ρv: This option represents the momentum flow rate of a fluid. Here, ρ represents the density of the fluid, and v represents the velocity of the fluid. Multiplying the density and velocity gives you the momentum flow per second of the fluid.
- D. Av/ρ: This option represents the inverse of the density. It does not directly represent a flow rate or a quantity related to fluid flow.
Q189. The dimension of coefficient of viscosity is:
- A. A
- B. B
- C. C
- D. D✓
Explanation: η = 𝐹×𝑑 𝐴×𝑣 Where F is the tangential force, d is the distance between two layers skidding over each other, A is the area and v is the velocity. By dimensional analysis, η = 𝑘𝑔.𝑚.𝑠 −2×𝑚 𝑚 2×𝑚𝑠 −1
Why the other options are wrong
- A. This is not correct dimension of coefficient of viscosity.
- B. This is not correct dimension of coefficient of viscosity.
- C. This is not correct dimension of coefficient of viscosity.
Q190. What should be the length of a simple pendulum whose period is 6.28 seconds at a place where g = 10 ms-2?
- A. 0.28 m
- B. 10.8 m
- C. 6.28 m
- D. 10 m✓
Explanation: 10 m: This option represents the correct length for the simple pendulum. The period of a simple pendulum is given by the formula T = 2π√(L/g), where T is the period, L is the length of the pendulum, and g is the acceleration due to gravity. Rearranging the formula, we have L = (T^2 * g) / (4π^2), where T = 6.28 s and g = 10 ms^-2. Plugging in these values, we get L = (6.28^2 * 10) / (4π^2) ≈ 9.99 m, which can be approximated as 10 m.
Why the other options are wrong
- A. 0.28 m: This option represents a specific length for the simple pendulum. However, it does not correspond to the correct length required for a period of 6.28 seconds.
- B. 10.8 m: This option represents another specific length for the simple pendulum. However, it does not correspond to the correct length required for a period of 6.28 seconds.
- C. 6.28 m: This option represents a length equal to the desired period of 6.28 seconds. However, it is not the correct length for a simple pendulum at a place where g = 10 ms^-2.
Q191. What should be the ratio of kinetic energy to total energy for simple harmonic oscillator?
- A. 1 − (x 2 / xo 2 )✓
- B. 1
- C. (xo 2 − x 2 )
- D. ½ (x 2)
Explanation: 𝐾𝐸 = 1 2 𝑚ω 2 (𝑥 0 2 − 𝑥 2 ) 𝑇𝑜𝑡𝑎𝑙 𝐸𝑛𝑒𝑟𝑔𝑦 = 1 2 𝑚ω 2 𝑥 0 2 Dividing the two terms gives us the ratio and the solution to the equationKE/E = 1 - (x^2/xo^2)Where x is the displacement from the equilibrium position and xo is the amplitude of the oscillation.This means that the ratio of kinetic energy to total energy is given by 1 minus the square of displacement divided by the square of the amplitude.Therefore, the correct answer is:1 - (x^2/xo^2)
Why the other options are wrong
- B. 1: This option represents a ratio of 1, indicating that the kinetic energy is equal to the total energy for a simple harmonic oscillator. However, this is not the correct ratio.
- C. (xo^2 - x^2): This option represents the difference between the square of the amplitude (xo^2) and the square of the displacement (x^2). However, this is not the correct ratio of kinetic energy to total energy.
- D. 1/2 * (x^2): This option represents half of the square of the displacement (x^2). This expression is not the correct ratio of kinetic energy to total energy.
Q192. An observer moves with velocity ‘vO’ towards a stationary source, then the number of waves received in one second is:
- A. A
- B. B
- C. C✓
- D. D
Explanation: For a stationary source and an observer moving towards the source the equation is: 𝑓 ' = 𝑓( 𝑣+𝑣 0 𝑣 )
Why the other options are wrong
- A. Incorrect as per formula
- B. Incorrect as per formula
- D. Incorrect as per formula
Q193. Strain energy in deformed energy is stored in the form of:
- A. Elastic Energy
- B. Potential Energy✓
- C. Plastic Energy
- D. Kinetic Energy
Explanation: For an object that is deformed energy as stored as the potential energy and is known as the Strain energy.Elastic energy is the energy stored in a deformed object when it undergoes elastic deformation. This energy is stored in the form of potential energy within the object's molecular or atomic bonds.Potential energy is a type of energy associated with the position or configuration of an object. In the case of a deforming train, potential energy is stored as the train's shape changes. This potential energy can be released or converted into other forms of energy, such as kinetic energy, when the train returns to its original shape or undergoes further deformation.Plastic energy Is not a correct term.Kinetic energy is the energy of motion. While a deforming train may have some kinetic energy due to its motion.
Why the other options are wrong
- A. Elastic energy is the energy stored in a deformed object when it undergoes elastic deformation. This energy is stored in the form of potential energy within the object's molecular or atomic bonds.
- C. Plastic energy Is not a correct term.
- D. Kinetic energy is the energy of motion. While a deforming train may have some kinetic energy due to its motion.
Q194. A wire of area of cross-section ‘A’ and original length ‘l’ is subjected to a load ‘L’. A second wire of the same material with an area is ‘2A’ and a length of ‘2l’ is subjected to the same load ‘L’. If the extension in the first wire is ‘X’ and the second wire is ‘Y’, find the ratio ‘X/Y’.
- A. 1:4
- B. 1:2
- C. 1:1✓
- D. 2:1
Explanation: To determine the correct ratio, we can use the formula for the extension of a wire under an applied load, which is given by Hooke's Law:Extension (ΔL) = (Load (L) * Length (l)) / (Area of Cross Section (A) * Young's Modulus (E))For the first wire: X = (L * l) / (A * E)For the second wire: Y = (L * 2l) / (2A * E)By simplifying the expressions, we find that X = Y, which means the extension in the first wire is equal to the extension in the second wire. Therefore, the correct ratio is 1:1.Hence, the correct option is c) 1:1, which represents the ratio of X/Y as 1:1.
Why the other options are wrong
- A. 1:4: This ratio implies that the extension in the first wire (X) is one-fourth of the extension in the second wire (Y).
- B. 1:2: This ratio implies that the extension in the first wire (X) is half of the extension in the second wire (Y).
- D. 2:1: This ratio implies that the extension in the first wire (X) is twice the extension in the second wire (Y).
Q195. Two sample of gases ‘1’ and ‘2’ are taken at same temperature and pressure but the ratio of number of their volume is V1:V2 = 2:3. What is the ratio of the number of moles of the gas sample?
- A. 3:2
- B. √2 :√3
- C. 4:9
- D. 2:3✓
Explanation: To determine the correct ratio, we can use the Avogadro's Law, which states that equal volumes of gases at the same temperature and pressure contain an equal number of molecules.Since the volumes of the gases are given as V1:V2 = 2:3, the ratio of the number of moles (n1:n2) will also be 2:3. This means that the correct option is d) 2:3, which represents the ratio of the number of moles of the gas sample.Hence, the correct option is d) 2:3, which represents the ratio of the number of moles of the gas sample.
Why the other options are wrong
- A. 3:2: This ratio implies that the number of moles of gas sample 1 (n1) is three times the number of moles of gas sample 2 (n2).
- B. √2 : √3: This ratio implies that the square root of 2 is the ratio of the number of moles of gas sample 1 (n1) to the square root of 3, which is the ratio of the number of moles of gas sample 2 (n2).
- C. 4:9: This ratio implies that the number of moles of gas sample 1 (n1) is four times the number of moles of gas sample 2 (n2).
Q196. Root mean square velocity of a gas having pressure ‘P’ and density ‘ρ’ is given by:
- A. √(3P/ρ)✓
- B. 3Pρ
- C. 3ρ/P
- D. √3ρ/P
Explanation: √3P/ρ: This option represents the correct equation for the root mean square velocity of a gas. The RMS velocity is given by the formula √(3ρ/P), where ρ is the density of the gas and P is the pressure.
Why the other options are wrong
- B. 3Pρ: This option does not represent the correct equation for the root mean square velocity. It is not a valid formula for calculating the RMS velocity of a gas.
- C. 3ρ/P: This option does not represent the correct equation for the root mean square velocity. It is not a valid formula for calculating the RMS velocity of a gas.
- D. √3ρ/P: This option represents the correct equation for the root mean square velocity of a gas. The RMS velocity is given by the formula √(3ρ/P), where ρ is the density of the gas and P is the pressure.
Q197. When the rate of a gas changes without a change in temperature, the gas is said to haveundergone:
- A. Isothermal Process✓
- B. Adiabatic Process
- C. Isochoric Process
- D. Isobaric Process
Explanation: An isothermal process is one in which there is no change in temperature. An adiabaticprocess is one in which there is no transfer of heat energy between the system and thesurroundings. An isochoric process is one in which the volume stays constant. An isobaricprocess is one in which the pressure is kept constant. Therefore, the answer is A.The term isothermal refers to as same temperature or no change in temperature, so according to statement the correct option will be option A isothermal process.An adiabatic process is one in which there is no transfer of heat energy between the system and the surroundings.isochoric process is one in which the volume stays constant.An isobaric process is one in which the pressure is kept constant.
Why the other options are wrong
- B. An adiabatic process is one in which there is no transfer of heat energy between the system and the surroundings
- C. isochoric process is one in which the volume stays constant.
- D. An isobaric process is one in which the pressure is kept constant.
Q198. What is 273 K on the Celsius scale of temperature?
- A. 0.15 °C
- B. 273.15 °C
- C. -0.15 °C✓
- D. -273.15 °C
Explanation: The explanation is given below:
Why the other options are wrong
- A. 0.15 °C: This option represents the temperature 273 K converted to the Celsius scale. However, the correct conversion for 273 K is not 0.15 °C.
- B. 273.15 °C: This option is incorrect.
- D. -273.15 °C: This option is not the correct conversion of 273 K to the Celsius scale. The correct conversion yields a positive value.
Q199. If heat ‘Q1 is absorbed in temperature ‘T’ and heat ‘Q2 is absorbed at temperature of the triple point of water, then the unknown temperature of the system (in K) is :
- A. 273.16
- B. 273.16 Q2/Q1
- C. 273.16 Q
- D. 273.16 Q1/Q2✓
Explanation: 𝑇 1 𝑇 2 = 𝑄1 𝑄2 The triple point of water is 0.01C or 273.16K. Inputting this value as T2 in equation above we get the answer.
Why the other options are wrong
- A. 273.16: This option represents the temperature 273.16 K. However, it does not account for the heat transfer (Q1 and Q2) mentioned in the question.
- B. 273.16 Q2/Q1: This option involves the ratio of Q2 to Q1. It suggests that the unknown temperature is calculated by multiplying the ratio of Q2 to Q1 with 273.16 K. However, this option does not provide a specific value for the unknown temperature.
- C. 273.16 Q: This option involves the heat transfer Q. It suggests that the unknown temperature is directly proportional to the heat transfer Q. However, this option does not provide a specific value for the unknown temperature.
Q200. If the fundamental logic gates are connected as:
- A. A
- B. B✓
- C. C
- D. D
Explanation: There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
Why the other options are wrong
- A. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
- C. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
- D. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
Q201. Which combinations of ten identical resistors each of 2 Ω gives rise to the resultant of 10.4 Ω?
- A. 5 Parallel, 5 Series✓
- B. 4 Parallel, 3 Series
- C. 3 Parallel, 4 Series
- D. 2 Parallel, 5 Series
Explanation: Use Ohm's Law to add parallel resistors. The equation is 1/RTotal = 1/R1 + 1/R2 + 1/R3 + … + 1/RLast. Hence 5 X ½ = 5/2. Total Resistance through parallel is ⅖. When resistors are in series their individual resistance is added to get the total resistance. So 5 X 2= 10 Ω. Adding this gives 10.4 Ω.
Why the other options are wrong
- B. it is incorrect.
- C. it is incorrect.
- D. it is incorrect.
Q202. If a resistor having resistance ‘R’ is cut into three equal parts, then theequivalent of parallel combination is:
- A. 6/R
- B. 3/R
- C. . R/9✓
- D. R/3
Explanation: Since wire with resistance R is cut in 3 equal parts therefore each part will have resistance R/3. Using: 1 𝑅 𝑇 = 1 𝑅 1 + 1 𝑅 2 +... 1 𝑅 𝑛 When we input R/3 as R1 , R2 and R3 we get the answer as RT = R/9.The original resistor is cut into three equal parts, so each part has a resistance of R/3.Now, we can calculate the equivalent resistance of the three parts in parallel:1/Req = 1/(R/3) + 1/(R/3) + 1/(R/3) = 3/R + 3/R + 3/R = 9/RTaking the reciprocal of both sides:Req = R/9
Why the other options are wrong
- A. As per the solution, this is an incorrect option.
- B. As per the solution, this is an incorrect option.
- D. As per the solution, this is an incorrect option.
Q203. A bar of length ‘L’ pivoted at ‘O’ is acted by a force ‘F’ at an angle ‘ϴ’ with vertical line. What is the moment of force?
- A. L sinϴ
- B. L cosϴ
- C. LF cosϴ✓
- D. LF sinϴ
Explanation: This option suggests that the moment of force is LF cosϴ. This is the correct answer. The moment of force, also known as torque, is calculated by multiplying the magnitude of the force (F) by the perpendicular distance (L) from the point of rotation (pivot) to the line of action of the force. The angle ϴ represents the angle between the force and the vertical line. The expression LF cosϴ correctly represents the moment of force in this scenario.
Why the other options are wrong
- A. This option suggests that the moment of force is L sinϴ. However, this is not the correct expression for the moment of force.
- B. This option suggests that the moment of force is L cosϴ. However, this is not the correct expression for the moment of force.
- D. This option suggests that the moment of force is LF sinϴ. However, this is not the correct expression for the moment of force.
Q204. The resistance of a piece of wire is 12 Ω. It is bent to form an equilateral triangle. What is the equivalent resistance between any two corners of the triangles?
- A. 1.3 Ω
- B. 2.0 Ω
- C. 4.0 Ω
- D. 2.7 Ω✓
Explanation: 2.7 Ω: This option suggests that the equivalent resistance between any two corners of the triangle is 2.7 Ω. This is the correct answer.When a wire is bent to form an equilateral triangle, each side of the triangle has the same resistance as the original wire.
Why the other options are wrong
- A. 1.3 Ω: This option suggests that the equivalent resistance between any two corners of the triangle is 1.3 Ω. However, this is not the correct answer.
- B. 2.0 Ω: This option suggests that the equivalent resistance between any two corners of the triangle is 2.0 Ω. However, this is not the correct answer.
- C. 4.0 Ω: This option suggests that the equivalent resistance between any two corners of the triangle is 4.0 Ω. However, this is not the correct answer.
Q205. Magnetic field strength is measured in:
- A. Wbm-1
- B. Wbm-2✓
- C. Wbm2
- D. Wb
Explanation: Wbm-2: This option suggests that magnetic field strength is measured in Wbm-2. The unit "Wbm-2" represents webers per meter square, which is correct.
Why the other options are wrong
- A. Wbm-1: This option suggests that magnetic field strength is measured in Wbm-1. The unit "Wbm-1" represents webers per meter squared, which is incorrect.
- C. Wbm2: This option suggests that magnetic field strength is measured in Wbm2. The unit "Wbm2" represents Weber squared per meter, which is incorrect.
- D. Wb: This option suggests that magnetic field strength is measured in Wb (weber). However, magnetic field strength is not measured in webers. Weber is the unit of magnetic flux, not magnetic field strength.
Q206. Force on the current carrying conductor per unit length is given by:
- A. IL sinϴ
- B. ILB
- C. IL
- D. IB sinϴ✓
Explanation: IB sinϴ: This option suggests that the force on a current-carrying conductor per unit length is given by IB sinϴ. This is the correct expression. The force on a current-carrying conductor is proportional to the product of the current (I), the magnetic field strength (B), and the sine of the angle (ϴ) between the current direction and the magnetic field direction.
Why the other options are wrong
- A. IL sinϴ: This option suggests that the force on a current-carrying conductor per unit length is given by IL sinϴ. However, this expression is incorrect.
- B. ILB: This option suggests that the force on a current-carrying conductor per unit length is given by ILB. This expression is also incorrect. The correct expression includes the sinϴ term, representing the component of the magnetic field perpendicular to the current direction.
- C. IL: This option suggests that the force on a current-carrying conductor per unit length is given by IL. However, this expression is incorrect. The force on a current-carrying conductor is dependent on both the current and the magnetic field, and the expression should include both terms.
Q207. In the case when the electrons lose all their kinetic energy (K.E.) in the first collision, the X-ray photon emitted has the following set of frequency and wavelength?
- A. fmax , λmin✓
- B. fmax , λmax
- C. fmin , λmax
- D. fmin , λmin
Explanation: fmax , λmin : This option suggests that when electrons lose all their kinetic energy in the first collision, the emitted X-ray photon will have maximum frequency ( fmax ) and minimum wavelength ( λmin ). According to the relationship between frequency and wavelength (c = λf, where c is the speed of light), as frequency increases, wavelength decreases. So, if the frequency is maximum, the wavelength should be minimum, and vice versa.
Why the other options are wrong
- B. fmax , λmax: This option suggests that when electrons lose all their kinetic energy in the first collision, the emitted X-ray photon will have maximum frequency ( fmax ) and maximum wavelength ( λmax ). This is also incorrect. As mentioned earlier, frequency and wavelength are inversely proportional, so they cannot both be maximum at the same time.
- C. fmin , λmax : This option suggests that when electrons lose all their kinetic energy in the first collision, the emitted X-ray photon will have minimum frequency ( fmin ) and maximum wavelength (λmax ). When the electrons lose all their kinetic energy, the emitted X-ray photon will have the minimum possible frequency and the maximum possible wavelength.
- D. fmin , λmin : This option suggests that when electrons lose all their kinetic energy in the first collision, the emitted X-ray photon will have minimum frequency ( fmin ) and minimum wavelength ( λmin ). However, this is incorrect. If the frequency is minimum, the wavelength should be maximum, as per the relationship between frequency and wavelength.
Q208. If ‘A’ is the fundamental dimension of ampere, then the dimension of magnetic field strength is:
- A. [MT2A-2]
- B. [MT-²A-1]✓
- C. [MT2A-2]
- D. [MT-2A-2]
Explanation: The following is the solution:
Why the other options are wrong
- A. Incorrect as per the formula.
- C. Incorrect as per the formula.
- D. Incorrect as per the formula.
Q209. The potential difference between the target and cathode of an X-ray tube is 20 kV and the current is 20 mA. What is the λmin of the emitted X-ray?
- A. 6.19 x 10-4 m
- B. 6.19 x 10-14 m
- C. 6.19 x 10-11 m✓
- D. 6.19 x 10-19 m
Explanation: Following is the correct solution:
Why the other options are wrong
- A. Calculations show that the correct value of wavelength is 6.19x10^-11. Hence this option is incorrect.
- B. Calculations show that the correct value of wavelength is 6.19x10^-11. Hence this option is incorrect.
- D. Calculations show that the correct value of wavelength is 6.19x10^-11. Hence this option is incorrect.
Q210. Which of the following spectra is most typical of the output of an X-ray tube?
- A. A✓
- B. B
- C. C
- D. D
Explanation: The graph, shown in option A, comprises of two types of X-rays, labeled in the graph presented below;1. Characteristic X-rays;These X-rays are produced on instances when outer-shell electrons fill a vacancy in the inner shell of an atom, releasing X-rays.2. Bremsstrahlung/Braking Continnuum;This release of X-ray is exclusive to instances where a charged, accelerated particle i.e. Electrons is decelerated, upon striking against a metal surface or any surface. The outcome is the release of electromagnetic radiation, in the form of photons.
Why the other options are wrong
- B. It is against the characteristics of X-rays.
- C. It is against the characteristics of X- rays.
- D. It is against the characteristics of X- rays.
Q211. Which of the following is the truth table for the logic gate:
- A. A✓
- B. B
- C. C
- D. D
Explanation: This a truth table of OR logic gate and the logic gate corresponds to OR gate. option A is correct.
Why the other options are wrong
- B. This a truth table of OR logic gate and the logic gate corresponds to AND gate. it is incorrect.
- C. it is incorrect option.
- D. it is incorrect option.
Q212. If the fundamental logic gates are connected as:
- A. A
- B. B✓
- C. C
- D. D
Explanation: There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
Why the other options are wrong
- A. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
- C. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
- D. There are 3 inputs/ gates in the given lohic gate. Two are NOR (OR+NOT) gates with an output of (Ā+B) and the third gate is an AND gate with an output of A.B.So, the answer should be B.
Q213. In Wilson Cloud Chamber which of the following tracks represented β-particles?
- A. A
- B. B✓
- C. C
- D. None of these
Explanation: Beta-particles produced 'two or three absolutely straight thread-like lines' from the direction of an impure radium salt source. The tracks produced by beta-particles were less clear than those produced by alpha-particles. Less energetic particles would spiral in the earth's field.The charged particles which produce tracks in a cloud chamber are alpha and beta particles (from radioactive atoms), and protons and muons (from space). Alpha and beta particles come from radioactive materials in our environment so the OPTION B represents Beta particles in wilson cloud chambers.
Why the other options are wrong
- A. The charged particles which produce tracks in a cloud chamber are alpha and beta particles (from radioactive atoms), and protons and muons (from space). Alpha and beta particles come from radioactive materials in our environment so OPTION B represents Beta particles in Wilson cloud chambers.
- C. The charged particles which produce tracks in a cloud chamber are alpha and beta particles (from radioactive atoms), and protons and muons (from space). Alpha and beta particles come from radioactive materials in our environment so OPTION B represents Beta particles in Wilson cloud chambers.
- D. This is not correct. Option B is correct
Q214. Identify the type of sentence Without a doubt, may he get the first position!
- A. Declarative Sentence
- B. Imperative Sentence
- C. Optative Sentence✓
- D. Exclamatory Sentence
Explanation: The sentence expresses a wish or desire specifically hoping that someone gets the first position. The phrase "may he" is a characteristic of optative sentences which express a wish or desire for someone or something.
Why the other options are wrong
- A. A declarative sentence states a fact but this sentence expresses a wish.
- B. An imperative sentence gives a direct command or instruction but this sentence expresses a desire not a command.
- D. An exclamatory sentence expresses strong emotions but while the sentence expresses a strong desire it's specifically a wish making it optative.
Q215. Identify the type of sentence Should I call or email you?
- A. Declarative Sentence
- B. Imperative Sentence
- C. Interrogative Sentence✓
- D. Exclamatory Sentence
Explanation: The sentence asks a question specifically inquiring about the preferred method of communication. The word "should" is used to seek advice or guidance, making it an interrogative sentence.
Why the other options are wrong
- A. A declarative sentence states a fact but this sentence asks a question.
- B. An imperative sentence gives a direct command or instruction but this sentence seeks guidance.
- D. An exclamatory sentence expresses strong emotions but this sentence is a neutral question.
Q216. Identify the type of sentence God showers his blessings.
- A. Declarative Sentence✓
- B. Imperative Sentence
- C. Optative Sentence
- D. Exclamatory Sentence
Explanation: The sentence states a fact or describes a situation, specifically that God showers his blessings. It's a neutral statement, simply declaring or asserting that something is the case.
Why the other options are wrong
- B. An imperative sentence gives a direct command or instruction, but this sentence doesn't tell anyone to do something.
- C. An optative sentence expresses a wish or desire, but this sentence states a fact, not a wish.
- D. An exclamatory sentence expresses strong emotions, but this sentence is a neutral statement.
Q217. Identify the type of sentence Mister, can you spare us for a while?
- A. Declarative Sentence
- B. Imperative Sentence
- C. Interrogative Sentence✓
- D. Exclamatory Sentence
Explanation: The sentence asks a question, specifically requesting permission or asking if someone is available to talk or meet. The word "can" is used to inquire about ability or willingness making it an interrogative sentence.
Why the other options are wrong
- A. A declarative sentence states a fact, but this sentence asks a question.
- B. An imperative sentence gives a direct command or instruction but this sentence asks for permission or availability.
- D. An exclamatory sentence expresses strong emotions but this sentence is a polite request.
Q218. Identify the type of sentence Wish you a happy journey together.
- A. Declarative Sentence
- B. Imperative Sentence
- C. Optative Sentence✓
- D. Exclamatory Sentence
Explanation: The sentence expresses a wish or desire, specifically hoping that someone has a happy journey together. The phrase "wish you" is a characteristic of optative sentences, which express a desire or wish for someone or something.
Why the other options are wrong
- A. A declarative sentence states a fact, but this sentence expresses a wish.
- B. An imperative sentence gives a direct command or instruction, but this sentence expresses a desire, not a command.
- D. An exclamatory sentence expresses strong emotions, but while the sentence expresses a positive sentiment, it's specifically a wish, making it optative.
Q219. Identify the type of sentence Please stop!
- A. Declarative Sentence
- B. Imperative Sentence✓
- C. Optative Sentence
- D. Exclamatory Sentence
Explanation: The sentence "Please stop!" is an imperative sentence, giving a direct command or instruction to the listener, telling them to stop what they are doing. Imperative sentences often begin with a verb, and sometimes include words like "please" to make the command more polite.
Why the other options are wrong
- A. A declarative sentence states a fact, but this sentence is giving a command, not stating a fact.
- C. An optative sentence expresses a wish or desire, but this sentence is giving a direct instruction, not expressing a wish.
- D. An exclamatory sentence expresses strong emotions, but this sentence is giving a command, not expressing emotion.
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