Etea Mdcat 2006 — Solved Past Paper with Answers

Q1. "Browned off " means:

• A. grilled properly
• B. bored
• C. discouraged✓
• D. cleaned

Explanation: The phrase 'browned off' is an informal British expression meaning to be annoyed, irritated, or dissatisfied. The correct answer is 'discouraged,' which aligns with the sense of frustration and dissatisfaction implied by the expression. 'Grilled properly' and 'cleaned' are unrelated to the emotional state described, and 'bored' only partially captures the meaning, as it lacks the intensity of irritation or dissatisfaction.

Q2. "Blow great trumpet / hom" refers to:

• A. boast✓
• B. violent flow of winds
• C. celebrate enthusiastically
• D. eruption of war

Explanation: The phrase 'blow one's own trumpet' is an idiomatic expression that means to boast or brag about one's own accomplishments. Option A, 'boast', is correct as it aligns with this definition. The other options are incorrect as they do not capture the meaning of this particular idiom. 'Violent flow of winds' and 'eruption of war' are unrelated to the context of self-promotion, and 'celebrate enthusiastically' does not imply the self-focused boasting implied by the expression.

Q3. Many ancient civilizations …………… on the banks of major rivers.

• A. dashed
• B. flourished
• C. sprawled✓
• D. succeeded

Explanation: The correct answer is 'sprawled' because it describes how ancient civilizations expanded and developed along riverbanks, taking advantage of the resources and fertile lands. 'Dashed' implies a swift movement and is not relevant to the context. 'Flourished' indicates prosperity but does not specify how they physically spread. 'Succeeded' refers to achieving success but does not describe the geographical aspect of civilization development.

Q4. Which one is an auxiliary?

• A. With
• B. On
• C. Do✓
• D. For

Explanation: The correct answer is 'Do.' In this question, 'Do' is the only auxiliary verb among the options provided. Auxiliary verbs, also known as helping verbs, are used alongside main verbs to create questions, negative statements, and various verb tenses. The other options, 'With,' 'On,' and 'For,' are prepositions that show the relationship between nouns or pronouns and other elements in a sentence.

Q5. "Homicide"

• A. is a poison
• B. means killing members of one's species
• C. means "munder"✓
• D. means "the murderer of one's own family

Explanation: The correct answer is Option C: means "munder". Homicide is derived from the Latin word "homicidium," which translates to murder. This term encompasses any unlawful killing of another human being. The other options provide incorrect definitions that do not align with the actual meaning of homicide.

Q6. She dresses with great—--------------- and that is how she impresses people.

• A. pride
• B. outrageousness
• C. ostentation✓
• D. panache

Explanation: Ostentation is characterized by pretentious or showy display; designed to impress. Hence option C is correct.

Q7. It is very difficult to relax while working with their new boss because he is a hard

• A. worker
• B. hearted
• C. taskmaster✓
• D. nut crack

Explanation: The correct answer is taskmaster because it describes someone who imposes strict or demanding tasks on others, which aligns with the sentence's implication that the boss is difficult to work with due to their demanding nature. The option 'worker' does not indicate the boss's demanding nature; 'hearted' is not used properly here as it needs an adjective to describe someone's nature; and 'nut crack' is not a recognized term for describing a person.

Q8. AUTOCRACY is the govemment of

• A. One person with absolute power✓
• B. lawyers fraternity
• C. Elected representatives of the masses
• D. intelligentsia

Explanation: Autocracy a system of government by one person with absolute power. Hence option A is correct.

Q9. 'The Bottom line is that we cannot ignore the cultural aspect in education'. The underlined expression means:

• A. most important thing✓
• B. the last line in a essay
• C. conclusion
• D. Trend

Explanation: Bottom line is a noun meaning the fundamental and most important factor. Hence, option A is correct.

Q10. His fondness _ makes his writings difficult to understand because most readers don't know the knewly invented words.

• A. archaic words
• B. sking
• C. advanced words
• D. neologism✓

Explanation: The correct answer is neologism, which means a newly coined word or expression. This matches the phrase 'newly invented words' used in the question. Archaic words are old and rare in modern usage, hence not newly invented. Sking appears to be a spelling error and does not relate to the question's context. Advanced words are complex or sophisticated but not newly invented, making them an incorrect choice here.

Q11. The building with numerous arhes looked _ in the midnight.

• A. Brightly
• B. Splendidly
• C. mysteriously
• D. magnificent✓

Explanation: The correct answer is 'magnificent.' In the sentence, the word needed to describe the appearance of the building is an adjective, not an adverb. 'Magnificent' accurately captures the grand and impressive nature of the building with numerous arches in the moonlight. The other options 'Brightly,' 'Splendidly,' and 'Mysteriously' are adverbs that focus on how something is done rather than describing the building itself.

Q12. The air we —------------ today has many harmful elements in it.

• A. Breathe✓
• B. are breathing
• C. breath
• D. have breathed

Explanation: Breathe is a verb we use for the process of inhaling and exhaling. In this sentence, 'breathe' is the correct verb form that matches the present tense structure. 'Are breathing' is in the present continuous tense, 'breath' is a noun, and 'have breathed' is in the present perfect tense, making them less suitable for this sentence.

Q13. In time of war, government do things which are Epedient. The underlined word means

• A. Endorsed by war council
• B. Concominant
• C. Need of hour✓
• D. Usefull but not necessarily right

Explanation: This option suggests urgency or necessity, which is the exact meaning of 'expedient' as used in the sentence.

Q14. The man sitting next to me on the plane was nervous because he _ before.

• A. had not flown✓
• B. did not fly
• C. has not flown
• D. has not been flown

Explanation: The use of “was” in the first part of the sentence and the word “before” at the end suggest it to be a past sentence. So we can rule out the second last option as it uses present perfect tense. The last option is incorrect itself as “been” is only used with perfect continuous tense. It will be wrong to use “ has been flown”, the correct structure for this will be, “has been flying”. Simple past tense is not a very suitable option as well. The correct use of tense here will be the past perfect tense. Past perfect tense states an action that happened ( had never flown ) before another action took place ( his first flight ). So this implies that he had not flown before his first flight. Now the complete sentence will be as follows:“The man sitting next to me on the plane was nervous because he had not flown before”.

Q15. The role of bacterial population in the large intestine of man is to;

• A. break down of cellulose
• B. synthesize some vitamins✓
• C. produce intestinal juice
• D. absorb water and mineral salts

Explanation: The large intestine is home to trillions of bacteria which are majorly involved in the production of vitamins (vit B1, B9, B7, B2, b5, vitamin K) and controlling growth of harmful bacteria.

Q16. The social organization of howling monkeys was studied by:

• A. Allen
• B. Thorpe
• C. Schjeldeup ebbe
• D. Carpenter✓

Explanation: The social organization of howling monkeys has been studied by several researchers. Among the options you provided, Allen, Thorpe, Schjelderup-Ebbe, and Carpenter, only one of them is directly associated with studying howling monkeys' social organization. The correct answer is Carpenter. Allen: It is unclear which specific Allen you are referring to, as there have been many researchers named Allen in various fields. Without further information, it is difficult to determine if any of them have specifically studied howling monkeys' social organization. Thorpe: Again, without more context, it is challenging to identify which Thorpe you are referring to. There have been multiple researchers with the last name Thorpe. However, it is worth mentioning that the name Thorpe is not commonly associated with studies on howling monkeys' social organization. Schjelderup-Ebbe: Konrad Lorenz is well-known for his work on ethology and animal behavior, including his studies on the pecking order in chickens, which introduced the concept of "dominance hierarchy" and "pecking order." However, Schjelderup-Ebbe is not typically associated with howling monkeys' social organization research. It's possible there may be some connection or reference I am not aware of, but it is not a commonly recognized association. Carpenter: Robert Carpenter is a primatologist known for his extensive research on howling monkeys' social organization. His work has focused on studying the behavior, ecology, and social dynamics of howling monkeys in their natural habitats. Carpenter's research has contributed significantly to our understanding of howling monkey social systems, including their vocalizations, group composition, and mating strategies. In conclusion, among the options provided, Carpenter is the researcher most closely associated with studying the social organization of howling monkeys.

Q17. A cell fails to detoxity the waste substances produced in it because it does not possess enough:

• A. lysosomes
• B. ribosome
• C. rough endoplasmic reticulum
• D. smooth endoplasmic reticulum✓

Explanation: The cell organelle responsible for the detoxification of waste substances is the smooth endoplasmic reticulum. The main functions of the smooth ER include synthesis of lipids/steroid hormones, detoxification of harmful metabolic byproducts and the storage and metabolism of calcium ions within the cell.

Q18. Vertebrate with one occipital condoyle is:

• A. pigeon✓
• B. frog
• C. monkey
• D. rabbit

Explanation: Occipital condyle is a rounded knob-like structure that is present at the base of the skull which articulates with the first vertebra. It helps animals to move their heads.Mammals and amphibians have two occipital condyles, reptiles and birds have only one. As monkeys and rabbits are mammas and frog is an amphibian, they all have 2 Ocs whereas a pigeon is a bird so it has one OC which is why it is the correct answer.

Q19. The flower of family gramineae (poaceae contains two scales below-ovary, which are called:

• A. glumes
• B. lemma & palea
• C. lodicules✓
• D. rochilla

Explanation: In the family Gramineae (Poaceae), the flower structure includes unique components like lodicules, which are small scales located below the ovary. These structures help facilitate the opening of the flower for fertilization. The other options, such as glumes, lemma, and palea, are different types of protective bracts associated with the spikelet but do not serve the same function as lodicules. 'Rochilla' is not a relevant term in this context, making it an invalid option.

Q20. The opening between right atrium and right ventricle is guarded by

• A. semi lunar valve
• B. tricuspid valve✓
• C. bicuspid valve
• D. semicircular valve

Explanation: The opening between the right atrium and right ventricle is guarded by the tricuspid valve.

Q21. The total of all the alleles in a population is called a:

• A. Genetic drift
• B. Genotype
• C. Gene pool✓
• D. Gene mutation

Explanation: The total set of gene copies for all genes in a population is referred to as its gene pool. (A: Genetic drift) is the change in the frequency of an existing gene variant in a population due to random sampling of organisms. (B: Genotype) is an organism's set of heritable genes that can be passed down from parents to offspring. (D: Gene mutation) is a permanent alteration in the DNA sequence that makes up a gene.

Q22. Which one of the following in glycolysis is a hydrogen carrier?

• A. ADP
• B. PGAL
• C. DPGA
• D. NAD✓

Explanation: Option D is correct because NAD (Nicotinamide adenine dinucleotide) functions as a hydrogen carrier in glycolysis. It accepts hydrogen atoms and electrons during the oxidation of glyceraldehyde-3-phosphate, converting into NADH. This is a critical step in energy extraction during glycolysis. The other options, ADP, PGAL, and DPGA, are involved in different roles within glycolysis or other metabolic pathways, but they do not function as hydrogen carriers.

Q23. The cells that play a vital role in the differentiation of various body parts are called:

• A. Ectodermal cells
• B. Mesodermal cells
• C. Endodermal cells
• D. All of the above✓

Explanation: During embryonic development, the cells in the early embryo undergo a process called differentiation, where they become specialized and give rise to different tissues and organs in the body. This process is controlled by specific groups of cells known as germ layers, which are formed during early embryonic development. These germ layers are the ectoderm, mesoderm, and endoderm.Ectodermal cells: The ectoderm is the outermost germ layer in the embryo. Ectodermal cells give rise to various tissues, such as the epidermis (outermost layer of the skin), hair, nails, tooth enamel, and parts of the nervous system, including the brain and spinal cord. They also differentiate into the sensory cells of the eyes, ears, and nose.Mesodermal cells: The mesoderm is the middle germ layer in the embryo. Mesodermal cells give rise to several important tissues and structures in the body, including muscles, bones, connective tissues, blood vessels, kidneys, heart, and reproductive organs. They also contribute to the development of the circulatory, skeletal, and excretory systems. Endodermal cells: The endoderm is the innermost germ layer in the embryo. Endodermal cells give rise to the epithelial lining of various organs, including the digestive tract (stomach, intestines), respiratory system (lungs), liver, pancreas, and urinary bladder. They also contribute to the formation of glands, such as the thyroid and thymus. Therefore, all three germ layers (ectoderm, mesoderm, and endoderm) play a vital role in the differentiation of various body parts during embryonic development.

Q24. Alternation of generations in plants is regarded a mechanism for:

• A. Achieving haploidy
• B. Promoting survival✓
• C. Producing diploidy
• D. Having no significance

Explanation: The concept of alternation of generations in plants involves a life cycle that alternates between a diploid sporophyte stage and a haploid gametophyte stage. This cycle allows plants to utilize both sexual and asexual reproduction, which is crucial for adapting to diverse environmental conditions. Sexual reproduction introduces genetic variation, while asexual reproduction enables rapid colonization. This adaptability is essential for plant survival, especially since plants are immobile and must cope with changing environments. Thus, the primary purpose of this cycle is to promote survival. Options A and C refer to haploidy and diploidy, which are components of the cycle but not its main goal. Option D is incorrect as alternation of generations is indeed significant for plant survival.

Q25. The individual with hare-lip shows which of the following condition?

• A. Cleft palate✓
• B. Polydactyly
• C. Hard-palate
• D. Microcephaly

Explanation: A cleft palate is a congenital condition often associated with a hare lip, involving an opening or split in the upper lip and/or roof of the mouth. This occurs when the developing facial structures in an unborn baby do not completely fuse. The other options are unrelated: Polydactyly involves extra digits; the hard palate is a normal part of the mouth's structure; and microcephaly is a different developmental condition affecting head size.

Q26. Receptors sensitive to smell are

• A. Mechanical
• B. Chemical✓
• C. Photoreceptors
• D. Georeceptors

Explanation: Receptors sensitive to smell are chemoreceptors, specifically olfactory receptors. These receptors detect chemical molecules in the air and translate them into neural signals that are processed as smells. Other types of receptors, such as mechanoreceptors, photoreceptors, and georeceptors, are specialized for detecting different types of stimuli: mechanical displacement, light, and balance, respectively.

Q27. Which hormone prepares the body for situations of stress and emergency?

• A. Adrenaline✓
• B. Non adrenaline
• C. Thyroxin
• D. Insulin

Explanation: Adrenaline triggers the body's fight-or-flight response. This reaction causes air passages to dilate to provide the muscles with the oxygen they need to either fight danger or flee. Adrenaline also triggers the blood vessels to contract to re-direct blood toward major muscle groups, including the heart and lungs.

Q28. Which of the following type of cytochromes is common in photosynthesis and respiration?

• A. Cyt “O”
• B. Cyt “a3”
• C. Cyt “b”✓
• D. Cyt “c”

Explanation: A membrane-bound cytochrome f-b complex participates in both respiratory and photosynthetic elevtron transport.

Q29. Anticodon of AUG will be:

• A. TAC
• B. UAC✓
• C. AUG
• D. CCA

Explanation: Anticodons are as follow:A = U( in case of RNA)A=T ( in case of DNA)C=G( same in both cases)

Q30. Which of the following is a freshwater sponge?

• A. Sycon
• B. Leucosolenia
• C. Euplectella
• D. Spongilla✓

Explanation: Spongilla is a genus of freshwater sponges in the family Spongillidae found in lakes and slow streams. Sycon is a genus of calcareous sponges belonging to the family Sycettidae. These sponges are small and are tube-shaped and often white to cream in color. Euplectella is a genus of glass sponges that includes the well-known Venus flower basket. So, the correct answer is option D.

Q31. In earthworms many Enzymes are present

• A. Typhlosole
• B. Intestinal caeca
• C. Esophagus
• D. Pharyngos mass✓

Explanation: The pharynx of an earthworm, particularly the pharyngeal mass, is where various digestive enzymes are secreted. These include protease, which breaks down proteins into amino acids, and mucin, which aids in softening the food. The other structures mentioned, such as the typhlosole, intestinal caeca, and esophagus, have roles in the digestive process but are not primarily responsible for enzyme production. The typhlosole increases absorptive surface area, the intestinal caeca have a minor role in digestion, and the esophagus is merely a passageway for food.

Q32. Fibrinogen is a protein produced by

• A. Gallbladder
• B. Liver✓
• C. Kidneys
• D. Lungs

Explanation: Fibrinogen is a protein produced by the liver, which plays a crucial role in blood clotting by being converted into fibrin during the clotting process. The gallbladder, kidneys, and lungs do not produce fibrinogen. The gallbladder stores bile, the kidneys filter blood, and the lungs facilitate gas exchange.

Q33. All the flowers come at the same level due to equal size of their pedicels in

• A. corymbs
• B. umbel✓
• C. catkin
• D. panicle

Explanation: The pedicel is a stalk or stem that supports a single flower. It connects the single flower to the inflorescence. It is usually seen in pedicellate flowers (e.g., Roses). The flowers without pedicels are called sessile flowers (e.g., Sunflower).In an umbel, each of the pedicels initiates from about the same point at the tip of the peduncle, giving the appearance of an umbrella-like shape.

Q34. A living tissue which in addition to its regular fianction also provides support to plants is:

• A. Xylem
• B. Collenchyma✓
• C. Sclerenchyma
• D. Parenchyma

Explanation: Collenchyma is living tissue that provides support to the plant as it has extra cellulose deposited in its cell wall the cell wall is non-lignified.

Q35. The control centre of speech is:

• A. Medulla oblongata
• B. Diencephalom
• C. Cerebrum✓
• D. Cerebellum

Explanation: The largest part of the brain, the cerebrum initiates and coordinates movement and regulates temperature. Other areas of the cerebrum enable speech, judgment, thinking and reasoning, problem-solving, emotions, and learning.

Q36. Filter feeders extract food particles from:

• A. Water✓
• B. Soil
• C. Air
• D. Blood

Explanation: Filter feeders primarily extract food particles from water. They possess specialized structures or mechanisms to filter out and capture small organisms or organic particles suspended in the water column. These organisms include various types of plankton, algae, and other microscopic organisms present in aquatic environments. Examples of filter feeders in water include baleen whales, certain species of fish, and many types of invertebrates like clams, mussels, and krill. Filter feeders do not typically extract food particles from soil or air. Soil contains organic matter and nutrients, but filter feeders are not adapted to extract food from this medium. Instead, organisms that feed on soil, such as earthworms, nematodes, and various microorganisms, employ different mechanisms, like ingestion and decomposition, to derive nutrients from organic matter in the soil. Similarly, while some organisms extract small particles from the air, they are not generally referred to as filter feeders. Airborne particles are usually captured through mechanisms such as trapping or sticking to surfaces like hairs or mucus membranes found in the respiratory systems of animals or the surface of plants. These particles may include pollen, dust, or spores. Examples of organisms that capture particles from the air include certain insects, like mosquitoes, which feed on pollen or nectar, and some birds that catch flying insects in flight. Finally, the option of blood does not apply to filter feeders. Filter feeders are not specialized to extract food particles directly from blood. Blood is a fluid found within the circulatory system of animals and is primarily used to transport nutrients, oxygen, and waste products throughout the body. Filter feeders do not target blood as a food source, and their feeding mechanisms are not adapted to extract nutrients from it. In summary, filter feeders primarily extract food particles from water, while soil, air, and blood are not typical sources of nutrition for these organisms.

Q37. On the basis of which of the following ratio we can prove law of independence assortment?

• A. 9:3:3:1✓
• B. 9:3:4
• C. 1:2:1
• D. 2:11

Explanation: The correct ratio for demonstrating the law of independent assortment is 9:3:3:1. This ratio results from a dihybrid cross where two heterozygous parents are crossed, and each trait is inherited independently according to Mendel's second law. This ratio is obtained by considering the combination of two pairs of alleles, each pair segregating independently during gamete formation. The other ratios provided do not demonstrate independent assortment: 9:3:4 is related to epistasis, 1:2:1 is typical of incomplete dominance in a monohybrid cross, and 2:11 does not represent a standard genetic ratio.

Q38. Photorespiration accurs when:

• A. Stomata are opened
• B. Day is humid
• C. Concentration of CO2 inside the leaf is high
• D. Concentration of O2 inside leaf is high✓

Explanation: Photorespiration occurs when Rubisco, an enzyme involved in photosynthesis, binds with O2 instead of CO2. This process is more likely when the concentration of O2 inside the leaf is high, which happens when stomata are closed to prevent water loss in hot and dry climates. Consequently, CO2 levels drop, and O2 levels rise, increasing the likelihood of photorespiration. Thus, option D is correct. The other options are incorrect because open stomata (option A) and high CO2 levels (option C) favor photosynthesis, and humid conditions (option B) typically result in open stomata, reducing the chance of photorespiration.

Q39. In geneaction the gene that mark the expression of another gene is formed as

• A. Hypostatic
• B. Epistatic✓
• C. Hemistatic
• D. Neostatic

Explanation: Epistatic is the gene that masks the expression of an allele at a separate locus.

Q40. Green house effect is NOT produced by the abundance of the gas called

• A. Methane
• B. CO2
• C. Nitrous oxide
• D. Sulphur dioxide✓

Explanation: The greenhouse effect is how heat is trapped close to Earth's surface by “greenhouse gases.” Greenhouse gases include CO2, methane, and nitrous oxide which are options A, B, and C respectively. Option D, SO2, is an atmospheric pollutant produced by volcanic eruptions and combustion engines. It is mainly responsible for acid rain, not the greenhouse effect, making it the correct answer.

Q41. The step in glycolysis in which energy transfer is not involved is:

• A. Glucose phosphate → fructose diphosphate
• B. Fructose diphosphate → DAP✓
• C. PGAL→ PGAP
• D. PGAP→ PGA

Explanation: Energy transfer here occurs by the transfer of phosphate group from one compound to another.

Q42. Which one among the following is in fact a fruit, but is available in a vegetable shop?

• A. Capsicum annuum✓
• B. Solanum tuberosum
• C. Medicago denticulata
• D. Bauhinia variegata

Explanation: The correct answer is Capsicum annuum. It is classified as a fruit because it develops from the ovary of a flower and contains seeds. Despite this, it is commonly sold in vegetable shops due to its culinary uses. On the other hand, Solanum tuberosum is a potato, a root vegetable. Medicago denticulata is a type of plant used as fodder, and Bauhinia variegata is a flowering tree, neither of which are typically found in a vegetable shop or classified as fruits.

Q43. How much energy will be fixed by the primary carnivores?

• A. 2317 Kcal
• B. 232 kcal
• C. 1564 kcal
• D. None of above.✓

Explanation: The correct answer is 'None of above.' This is because as organisms move up trophic levels, there is a significant loss of energy, with only a small percentage being transferred to the next trophic level. Without specific information on the number of herbivores or primary carnivores, it is impossible to determine the exact amount of energy that will be fixed by the primary carnivores. Therefore, the correct answer is 'None of above.'

Q44. The word SEISMOLOGY stands for:

• A. An instrument for detecting earthquakes
• B. Study of sea creatures
• C. A branch of Astrology
• D. A scientific study of earthquakes✓

Explanation: The correct answer is that seismology is the scientific study of earthquakes. The term originates from the Greek word 'seismos' meaning 'earthquake' and 'logia' meaning 'study'. Other options are incorrect because: A seismograph is an instrument, not a field of study; marine biology involves sea life, not seismic activity; and astrology is concerned with celestial phenomena, not geological events.

Q45. Blood cells are produced by:

• A. Liver
• B. Spleen
• C. Bone marrow✓
• D. Heart

Explanation: Blood cells are produced in the red bone marrow from hematopoietic stem cells. These stem cells differentiate into various types of blood cells, including red blood cells, white blood cells, and platelets. The liver and spleen are involved in the breakdown and recycling of old or damaged red blood cells but do not produce them. The heart's function is to pump blood, not to produce blood cells.

Q46. Organs of locomotion in earth worm are:

• A. Papillae
• B. Setae✓
• C. Pseudopodia
• D. Cuticle

Explanation: Organs of locomotion in earth worms are setae. Setae are present on parapodia on the body wall or embedded in sacs.

Q47. Gonorrhea is a sex disease caused by:

• A. Bacteria✓
• B. Virus
• C. Parasite
• D. None of the above

Explanation: Gonorrhea is a sexually transmitted infection caused by the gram-negative bacterium Neisseria gonorrhoeae. This bacterium infects the mucous membranes of the reproductive tract, mouth, throat, eyes, and rectum. Option A is correct because it identifies the type of microorganism responsible for the infection. Option B is incorrect because viruses, such as the ones causing HIV or herpes, are not responsible for gonorrhea. Option C is incorrect as parasites cause different diseases, such as trichomoniasis. Option D is incorrect as it suggests none of the options are correct when, in fact, one is.

Q48. Which of the following is an inactive enzyme without its cofactor?

• A. Coenzyme
• B. Apoenzyme✓
• C. Holoenzyme
• D. Denatured enzyme

Explanation: The correct answer is apoenzyme. An apoenzyme is the protein part of an enzyme that is inactive on its own. It requires the presence of a cofactor to become a holoenzyme, which is the active form. In contrast, a coenzyme is a type of cofactor, not an enzyme, and a holoenzyme is an enzyme with its cofactor attached, making it active. A denatured enzyme is one that has lost its functional shape and activity due to external factors, not due to the absence of a cofactor.

Q49. Laiba is trying to determine the percentage of protein in bears because she is a

• A. Biochemist✓
• B. Microbiologist
• C. Physiologist
• D. Mycologist

Explanation: Laiba is a biochemist who is trying to determine the percentage of protein, a biomolecule, in beans. Moreover, a biochemist deals with the branch of science concerning the chemical processes taking place within an organism.

Q50. Which of these are carriers of genetic information?

• A. rRNA
• B. mRNA
• C. DNA✓
• D. Nucleotides

Explanation: A DNA molecule is a double helix carrying the genetic information of an organism. It encodes all the genetic instructions involved in the growth and development of an individual. Genes, which are fragments of DNA, are basic hereditary units.

Q51. Genome of which of the following consists of a single molecule of DNA?

• A. HAV
• B. HBV✓
• C. HCV
• D. HIV

Explanation: The correct answer is HBV. HBV, also known as Hepatitis B Virus, has a single circular double-stranded DNA genome. This genetic makeup sets it apart from the other options, which either have single-stranded RNA genomes (HAV, HCV, HIV) or undergo reverse transcription from RNA to DNA (HIV). Understanding the genetic material of each virus is crucial in identifying the correct answer.

Q52. Lithotripsy is a technique to:

• A. Remove kidney stones without surgery✓
• B. Remove kidney stones with surgery
• C. Treat kidney with medicines
• D. Remove appendix

Explanation: Lithotripsy involves the treatment of stones in the kidneys or ureters by using high-energy shock waves, breaking the stones which can then be passed by urine. It is a non-invasive, nonsurgical method and is highly effective for kidney stones that are very large to be passed in the urine.

Q53. Which one of the following plants feeds on water mites?

• A. Nepenthes
• B. Utricularia✓
• C. Dionea
• D. Sundew

Explanation: Drosera or sundew is a carnivorous plant found in moist, acidic, and nutrient-deficient soils. Such places are home to mosquitos and other insects and drosera feed on these to fulfill their nitrogen needs.

Q54. Goiter is caused by a deficiency of

• A. Sodium in water
• B. Calcium in water
• C. Iodine in water✓
• D. Sugar in water

Explanation: Goiter is caused by an iodine deficiency, which is vital for the production of thyroid hormones. The thyroid gland enlarges in an attempt to capture more iodine from the bloodstream. Iodine is found in various food sources, including iodized salt, seafood, and certain types of seaweed. Sodium, calcium, and sugar do not directly affect thyroid hormone production and are not related to the development of goiter.

Q55. Which one of the following is found in plant cells only?

• A. Peroxisomes
• B. Lysosomes
• C. Glyoxisomes✓
• D. Ribosomes

Explanation: Glyoxisomes are specialized organelles found only in plants. These contain enzymes for the glyoxylate cycle, through which fats are converted into carbohydrates (gluconeogenesis). These are found in germinating seeds and are responsible for fat metabolism.

Q56. Neuron that carries messages from sense organ to the central nervous system is:

• A. Afferent neuron✓
• B. Efferent neuron
• C. Associative neuron
• D. Interneuron

Explanation: Afferent neurons, also known as sensory neurons are responsible for establishing a link between the sensory organ and the central nervous system by conducting impulses toward the brain and spinal cord.

Q57. Corpuscular animals are active during:

• A. Night
• B. Day
• C. Twilight✓
• D. Spring

Explanation: Crepuscular animals are active during the twilight period, which is the time between day and night. Nocturnal animals are active during the night, diurnal animals are active during the day, and spring is a season rather than a time of day. Therefore, the correct answer is option C:Twilight.

Q58. Red tides in oceans are produced by:

• A. Diatoms
• B. Dinoflagellates✓
• C. Water molds
• D. Myxomycota

Explanation: The rapid increase in the population of red dinoflagellate (a type of algae), causes the sea to appear red, which is responsible for the occurrence of red tides.

Q59. The cartilage present in trachea is:

• A. Fibrous
• B. Hyaline✓
• C. Elastic
• D. Neurotic

Explanation: Hyaline cartilage is found at the ends of long bones and in the nose at the larynx and trachea.

Q60. Rabbits, pabulus, rats grasshoppers and grasses constitute a

• A. Habitat
• B. Biome
• C. Community✓
• D. Population

Explanation: A community is a group or association of populations of two or more different species occupying the same geographical area at the same time.

Q61. Size of the flower of chrysanthemum may be enlarged by removing

• A. All leaves
• B. A few leaves
• C. All branches except one
• D. All floral bud except one✓

Explanation: Removing all floral buds except one is the correct method to promote the growth of larger chrysanthemum flowers. By focusing the plant's energy on a single bud, it can develop into a larger flower. The other options either hinder the plant's growth or do not effectively promote larger flower size.

Q62. A peptide bond is formed between:

• A. An aldehyde group and an amino group
• B. An aldehyde group and an ester group
• C. An aldehyde group and a carboxyl group
• D. A carboxyl group and an amino group✓

Explanation: A peptide bond is a covalent bond that forms between the carboxyl group of one amino acid and the amino group of another amino acid. This bond formation results in the release of a molecule of water (a condensation reaction). None of the incorrect options involve the carboxyl and amino groups necessary for peptide bond formation. Instead, they incorrectly mention aldehyde and ester groups, which do not participate in this specific type of bonding.

Q63. The opening and closing of stomata are controlled by which of the following factor(s)?

• A. Sugar✓
• B. pH
• C. Potassium
• D. All of the above

Explanation: The opening and closing of stomata are primarily controlled by the conversion of starch to sugar and vice versa in guard cells. During the daytime, sugar increases osmotic pressure, leading to stomata opening, while at night, starch reduces osmotic pressure, causing stomata closure. While pH and potassium are important factors in plant physiology, they are not the main drivers of stomata regulation through the starch-sugar interconversion mechanism.

Q64. At constant temperature, as the pressure of a gaseous mixture in equilibrium increases, the equilibrium constant

• A. remains constant✓
• B. increase
• C. decrease
• D. varies

Explanation: When the pressure of a gaseous mixture in equilibrium increases at constant temperature, the equilibrium constant remains constant. This is because changes in pressure do not affect the equilibrium constant, which is determined solely by the concentrations of the reactants and products. The other options are incorrect because pressure changes do not cause the equilibrium constant to increase, decrease, or vary; it stays the same due to the equilibrium position being unaffected by pressure changes at constant temperature.

Q65. Na+ is isoelectronic with:

• A. Mg
• B. He
• C. Fe
• D. Ne✓

Explanation: Isoelectronic species have the same number of electrons. In this case, Na+ has 10 electrons after losing one to become an ion. Among the options, only Neon (Ne) also has 10 electrons, making it isoelectronic with Na+. Mg, He, and Fe have different electron counts, so they are not isoelectronic with Na+.

Q66. Fruit juices are often sold in aluminum cans. What is the most important reason?

• A. Aluminium can be recycled
• B. Aluminium is light
• C. Aluminium is cheaper
• D. Aluminium is resistant to corrosion✓

Explanation: It is because aluminium is resistant to corrosion by organic acids.

Q67. Consider the following equation: N2+O2 _ 2NO. The partial pressure (ln atm) of N2 under normal atmospheric pressure

• A. 0.05
• B. 0.25✓
• C. 0.35
• D. 0.45

Explanation: Partial pressure = moles of substance/total moles * total pressure =moles of N2/total moles * total pressure =1/4 * 1 atm = 0.25

Q68. Compounds that tend to donate electron pairs are known as Lewis acid or nucleophiles. Which one of the following is not a Lewis acid?

• A. CH3-NH2
• B. PH3
• C. AlCl3✓
• D. H2O

Explanation: A Lewis base is a substance that can donate an electron pair. Option C, AlCl3, is the correct answer as it acts as a Lewis acid due to its ability to accept electron pairs to complete its octet. In contrast, CH3-NH2, PH3, and H2O all have lone pairs of electrons that can be donated, classifying them as Lewis bases.

Q69. Which of the following reagents can be used to identify Ni+2 ions in solution?

• A. Ethylenediamine
• B. potassium ferrocyanide
• C. dimethylglyoxime✓
• D. potassium permanganate

Explanation: When identifying Ni+2 ions, dimethylglyoxime is the reagent of choice. Adding dimethyl glyoxime to a solution of Ni+2 ions along with ammonium hydroxide results in the formation of a bright red precipitate. This distinctive color change indicates the presence of Ni+2 ions. The other options, such as ethylenediamine, potassium ferrocyanide, and potassium permanganate, do not react in a way that specifically identifies Ni+2 ions, making them incorrect choices.

Q70. Which one of the following molecules does not contain nitrogen?

• A. Aniline
• B. Pyridine
• C. Hydrazine
• D. Naphthalene✓

Explanation: Option D is correct as it is an aromatic hydrocarbon containing two fused benzene rings with the formula C10H8 hence it does not contain nitrogen.

Q71. What product is obtained when methyl magnesium chloride reacts with ammonia?

• A. Methane✓
• B. Methylamine
• C. Ethylamine
• D. Methyl chloride

Explanation: When methyl magnesium chloride reacts with ammonia, the product obtained is methane. This is because Grignard reagents, such as methyl magnesium chloride, are basic and can accept protons from ammonia, resulting in the formation of methane and H2NMgCl. The other options, methylamine, ethylamine, and methyl chloride, are not the correct products formed in this reaction and can be eliminated based on the properties of the reactants.

Q72. Which of the following cannot be displaced from their salt solution by cell?

• A. Ag
• B. Au
• C. Al
• D. Zn✓

Explanation: In a displacement reaction, a more reactive metal can displace a less reactive metal from its salt solution. Zinc (Zn) is more reactive than copper, which is often used as a reference point in the reactivity series. Therefore, zinc cannot be displaced by copper from its salt solution. Conversely, metals like silver (Ag), gold (Au), and platinum are less reactive than copper and can be displaced from their salt solutions by copper or other more reactive metals. This understanding is based on the reactivity series, which orders metals by their ability to displace others from solutions.

Q73. For the atomic numbers given below, which pair of elements will have the same chemical properties?

• A. 13,22
• B. 3,11✓
• C. 4,24
• D. 2,4

Explanation: Option B is correct as the elements with atomic numbers 3 and 11 are Lithium and sodium, respectively which are both in the same group, hence they have the same chemical properties.Elements in the same group have the same number of valence electrons and thus have similar chemical properties.

Q74. 74g of calcium hydroxide will yield OH ions:

• A. 178
• B. 34g✓
• C. 51g
• D. 40g

Explanation: 74g of Ca(OH)2 equals 1 mole since the molar mass is 74 g/mol. The dissociation of Ca(OH)2 produces 2 moles of OH ions for every mole of Ca(OH)2. Each OH ion has a molar mass of 17g/mol, so 2 moles produce 34g of OH ions (17g/mol x 2). Thus, the correct answer is 34g. Options 178g, 51g, and 40g do not match the stoichiometric calculation for the amount of hydroxide ions produced from the dissociation of 74g of Ca(OH)2.

Q75. Which of the following pairs has the same electronic structure?

• A. Ar & Cl-✓
• B. Ca & Ar
• C. Mg and Na
• D. Ag & Sn

Explanation: Argon has 18 electrons. The chloride ion also has 18 electrons.

Q76. Which one of the Grignard reactions below could give rise to CH3CH3CH(OH)CH2CH3?

• A. Propane and methyl Grignard
• B. Methyl ethyl ketone and methyl
• C. Propanaldehyde and ethyl Grignard✓
• D. None of these

Explanation: The addition of Grignard reagent to aldehydes leads to the production of secondary alcohol, and the addition of ketone leads to the production of tertiary alcohol. As the alcohol produced in the question is secondary, the correct option would be the one with the reaction of aldehyde with grignard reagent, hence option C.Option A is incorrect as alkanes do not directly react with grignard to form alcohol; grignard reacts with alcohol to produce alkane.Option B is incorrect, as with ketone, a tertiary alcohol is formed, which is not the case in the question.

Q77. In glass manufacturing process, annealing is done for the prevention of

• A. Relieving internal stress✓
• B. Removing air bubbles
• C. Eliminating impurities
• D. Enhancing surface shine

Explanation: Annealing is a vital process in glass manufacturing aimed at relieving internal stresses that develop during cooling. This controlled cooling allows the glass to stabilize, reducing the risk of shattering under thermal stress. While removing air bubbles is essential, it occurs earlier in the production stages, not during annealing. Similarly, eliminating impurities takes place during the refining stage, and enhancing surface shine is achieved through separate polishing or coating processes, making those options incorrect.

Q78. If 28.0g nitrogen gas is reacted with 8.0g of hydrogen gas to form ammonia, the limiting reactant among the two will be:

• A. N2✓
• B. H2
• C. both (a) & (b)
• D. None of these

Explanation: The balanced chemical equation for the production of ammonia is: N2 + 3H2 → 2NH3. From this equation, 1 mole of nitrogen reacts with 3 moles of hydrogen. Calculate the moles of each reactant: 28.0g of N2 is 1 mole (since the molar mass of N2 is 28.0 g/mol), and 8.0g of H2 is approximately 4 moles (since the molar mass of H2 is 2.0 g/mol). Given this, the reaction requires 3 moles of H2 for every mole of N2. Hence, the 4 moles of H2 are in excess, making N2 the limiting reactant. Option A is correct. Options B, C, and D are incorrect because hydrogen is in excess, and only one reactant can be the limiting reactant.

Q79. The unit f Kc or the system N2O4 g ----------- 2NO2 g

• A. dimension (i.e., with no unit)
• B. mole dm3
• C. mole dm-3✓
• D. mole2 dm3

Explanation: The correct unit for the reaction N2O4 g → 2NO2 g is mole dm-3, as it represents the concentration of the substances involved in the reaction. This unit accounts for the balanced equation and the stoichiometry of the reaction. The other options are incorrect because they either wrongly assume no unit, combine units incorrectly, or misapply the units based on the reaction's stoichiometry.

Q80. What is the trade name of tetralluoroethylene polymer?

• A. Polystyrene
• B. Bakelite
• C. Nylon
• D. Teflon✓

Explanation: The correct answer is Option D:Teflon. The trade name of tetralluoroethylene polymer is PTFE, which is commonly known as Teflon. Polystyrene, Bakelite, and Nylon are different types of polymers with their specific chemical compositions and properties, but they are not related to tetralluoroethylene polymer.

Q81. In a closed room of 1000m 'a perfume boiler is opened up. The room develops a smell. This is due to which property of gases?

• A. diffusion✓
• B. viscosity
• C. density
• D. none of the above

Explanation: Diffusion is the net movement of gases from a region of higher concentration to a region of lower concentration. Gases spread due to diffusion down the diffusion gradient.

Q82. The emf of a galvonic cell can be calculated from:

• A. The size of the electrode
• B. The pH of the solution
• C. The amount of metal in the anode
• D. The values of the half cell✓

Explanation: For a galvanic cell, emf can be calculated by standard reduction potentials for two half cells. Emf is independent of pH except for the reactions involving H+ or OH- ions.Emf is independent of shape and size of electrodes,distance between electrodes and the amount of electrolyte.

Q83. Which of the following is NOT correct in case of carboxylic acids?

• A. they are polar molecules
• B. they form H-bonds
• C. they are stronger than mineral acids✓
• D. they have higher boiling points than their corresponding alcohols

Explanation: Mineral acids are stronger acids than carboxylic acids because mineral acids are completely ionized, whereas carboxylic acids are partially ionized.

Q84. The total energy of a H-atom in its ground state is:

• A. Negative (-Ve)✓
• B. Positive (+Ve)
• C. Zero
• D. None

Explanation: In the hydrogen atom, the force we are primarily referring to is the attractive force acting between the nucleus and the electron and this is obviously electrical in natureWe know for a fact from Coloumb’s Law, that the electrostatic force between two like charges is positive in sign, while that between two unlike charges is negative in sign; Hence negative force means that it is attractive in nature;Therefore, this negative force vector and its multiplied value with the displacement vector (which is always considered positive since the nucleus is the origin) gives the value of the electron’s energy in the negative sign hence option A is correct.

Q85. When ethanol is treated with fehling's solution. It gives a precipitate of:

• A. Cu
• B. CuO
• C. Cu2O✓
• D. Cu2O + Cu2O3

Explanation: Fehling solution is reduced by aldehydes and a red precipitate of Cu2O is obtained.

Q86. The Cl Atom attached to benzene ring is:

• A. m-directing
• B. o-directing
• C. o -& p -directing & deactivating✓
• D. o -& p -directing & activating

Explanation: Chlorine has a lone pair, so it can donate electrons to the benzene ring. Chlorine has high electronegativity, so it can withdraw the electron density from the ring. Chlorine increases electron density at the ortho and Para positions and decreases at the meta position, so it is ortho-para-directing.

Q87. Acetic anhydride is obtained from acetyl chloride in the reaction with:

• A. P2O5
• B. H2SO4
• C. +CH3COONa✓
• D. CH3COOH

Explanation: Acetyl chloride reacts with sodium acetate to give acetic anhydride.

Q88. Which form of matter possesses a higher magnitude of internal energy?

• A. Gaseous matter✓
• B. Solid matter
• C. Liquid matter
• D. all have the same magnitude

Explanation: Internal energy is defined as the sum of kinetic and potential energies associated with the random motion of atoms in a substance, and consequently, it depends on temperature and the state of matter. As can be seen from the image, it can be deduced that Temperature effects the kinetic energy of atoms, while change of state effects their potential energy. Hence, as substance changes from Solid to liquid and from liquid to gas, its particles move apart, potential energy increases, and internal energy increases.

Q89. A bottle of dry NH3 and a bottle of dry HCI connected through a long tube are opened simultaneously of both ends. The white NHCl ring formed will be

• A. at the center of the tube
• B. near the NH3 bottle
• C. near the HCl bottle✓
• D. throughout the length of the same tube

Explanation: When connecting the two bottles, the two gases will diffuse into each other.The rate of diffusion is inversely proportional to the square root of molecular mass.Considering the molecular masses (NH3 = 17 and HCl = 36.5), HCl, being the heavier gas, will diffuse slower (cover less distance), while the lighter gas NH3 will diffuse faster (cover more distance). So the white ring of NH4Cl (formed by the reaction of two gases) will be closer to the HCl bottle.This case is explained in option C.A, B, and D do not fit the relation between rate of diffusion and Molecular mass.

Q90. When β -particle is emitted from lead(82Pb212), the mass number and charge number of bismuth formed are

• A. 83Bi212✓
• B. 81Bi210
• C. 85Bi210
• D. None of these

Explanation: When a β-particle, which is an electron, is emitted from the nucleus during beta decay, a neutron is transformed into a proton. As a result, the atomic number (proton number) of the element increases by 1, but the mass number remains unchanged. Therefore, when a β-particle is emitted from lead (82Pb212), the resulting element is bismuth with an atomic number of 83 and a mass number of 212, denoted as 83Bi212. Option A correctly reflects these changes. Option B has an incorrect atomic number and mass number, while Option C incorrectly increases the atomic number by more than 1. Option D is incorrect as there is a valid answer among the provided options.

Q91. Acetadeftyde on oxidation by Na, Cr,O/H SO, gives:

• A. CH3COOH✓
• B. C2H5OH
• C. OHC.OHC
• D. None of the above

Explanation: An aldehyde on oxidation with an oxidizing agent (such as one given in qs) gives its respective carboxylic acid. A is a carboxylic acid.

Q92. Which is the correct formula of ammonium carbamate?

• A. H2NCONH2
• B. NH4COONH4
• C. H2NCOONH2
• D. NH2COONH4✓

Explanation: Ammonium carbamate is a salt formed by the reaction of ammonia with carbon dioxide or carbamic acid. It has formula [NH₄][H₂NCO₂].The reaction for its formation is 2NH 3 + CO 2 → [NH 2CO 2][NH 4]

Q93. Uncertainly principle can be expressed as:

• A. Momentum-position uncertainty: px = h
• B. Energy-time uncertainty: ET = h
• C. Both (a) and (b) together✓
• D. None of the above

Explanation: The uncertainty principle arises from the wave-particle duality.A quite accurate measurement of one observable involves a relatively large uncertainty in the measurement of the otherIt is expressed in terms of a particle's momentum and position, i.e.p x=h and can alternatively be expressed in terms of Energy and time, i.e., E T=h, so option C is correct.

Q94. The lowest vapor pressure is exerted by:

• A. Water
• B. Kerosene oil
• C. Mercury✓
• D. rectified spirit

Explanation: Vapor pressure is determined by the strength of intermolecular forces, with weaker forces leading to higher vapor pressure. In this case, mercury has the lowest vapor pressure because it has the strongest intermolecular forces compared to water, kerosene oil, and rectified spirit. This is why mercury is the correct answer. Water has stronger intermolecular forces than kerosene oil, rectified spirit, and mercury, resulting in higher vapor pressure. Kerosene oil has weaker intermolecular forces than water and mercury, leading to higher vapor pressure. Rectified spirit falls between kerosene oil and water in terms of intermolecular forces, resulting in higher vapor pressure than mercury.

Q95. 1 atomic mass unit (amu) in terms of energy is nearly equal to:

• A. 931 KeV
• B. 931 MeV✓
• C. 39 MeV
• D. 139 KeV

Explanation: The correct answer is Option B: 931 MeV. By utilizing the mass-energy equivalence formula E=mc^2, we calculate that 1 atomic mass unit (amu) is equal to 931 MeV. This conversion is based on the speed of light and the mass of an atomic unit.Option A, C, and D are incorrect as they do not represent the accurate energy equivalent of 1 amu, as calculated through the mass-energy equivalence formula.

Q96. Which of the following reaction show nucleophilic substitution of alkyl halideR-X?

• A. RX+H
• B. RH+HX✓
• C. 2RX+2Na-R-R+2NX
• D. R-X Mg-RMX

Explanation: The reaction of RX with KCN is a neucleophilic substitution reaction, as CN is a nucleophile that attacks the electrophilic carbocation.

Q97. A metal form strong base salts and stable carbonates. The metal is:

• A. Transition metal
• B. Alkali metal✓
• C. Alkaline earth metal
• D. None of above

Explanation: Group 1 elements, known as Alkali metals, fit the criteria of forming strong base salts and stable carbonates due to their low polarizing power. This is why Option B is the correct answer. The other options, such as Transition metals and Alkaline earth metals, do not exhibit the same characteristics as described in the question.

Q98. Which of the following oxy acids of chlorine is least oxidizing in nature"?

• A. HOCl✓
• B. HCIO2
• C. HClO3
• D. HClO4

Explanation: The oxidizing power of oxy acids of halogens increases as the oxidation number of the halogen in the compound increases. HOCl has the lowest oxidation number of Chlorine in it (+1), so it is the least oxidizing agent.Oxidation numbers for chlorine in B, C, and D are HClO2 = +3, HClO3 = +5, and HClO4 = +7, which are all higher than +1, so A is the correct option.

Q99. Which one is non-polar but contains polar bonds:

• A. HCl
• B. HF
• C. H2O
• D. CO2✓

Explanation: CO2 is the correct answer because even though it contains polar bonds between C and O, its linear molecular geometry results in the dipoles cancelling out, making the molecule non-polar overall. HCl, HF, and H2O are polar molecules with polar bonds due to the electronegativity differences between the atoms.

Q100. Which of the following is correct?

• A. Molecularity of a reaction is always the same as the order of reaction
• B. In some cases, the molecularity of a reaction is the same as the order of reaction✓
• C. Molecularity of a reaction is always greater than the order of reaction
• D. All statements above are correct

Explanation: True for elementary reactions, where the rate law can be written directly from the stoichiometry.Example: A→productsA → productsA→products (unimolecular) → order = 1, molecularity =1.

Q101. O2 gas is chemically inert at room temperature because:

• A. Atoms in the O2 molecules are held by a double bond✓
• B. 0-0 bonds are strong
• C. The amount of metal in the anode
• D. All of the above

Explanation: Atoms in an Oxygen molecule are held together by a double bond. O-O single bonds have a bond length of 1.48 angstrom, while O-O double bonds have a bond length of 1.21 angstrom. Double bonds are stronger because they hold the atoms closer together and make them difficult to break. Hence, more energy is required to break multiple bonds as compared to single bonds. This stability of the oxygen molecule makes it chemically inert at room temperature. Option A provides the correct explanation based on this concept. Options B, C, and D are incorrect as they do not address the specific reason for the inertness of O2 gas.

Q102. 2% solution by weight of sodium chloride solution is prepared. The molality of the solution is:

• A. 0.34 molal✓
• B. 0.25 molal
• C. 2 molals
• D. 0.02 mol

Explanation: 2% solution by weight means 2 grams of NaCl is dissolved per 100 grams of water. No. of moles = given mass/ molar mass = 2/58.5= 0.034Molality = no of moles / mass of solution in kg= 0.034/0.1= 0.34 Molal

Q103. For a reversible reaction to reach on equilibrium state the reaction said to be carried out in

• A. Glass vessel
• B. Iron vessel
• C. Open vessel
• D. Closed vessel✓

Explanation: At equilibrium, the rate of forward reaction equals the rate of reverse reaction. There is no net change in the concentration of the substances involved. This must happen in a closed vessel so that no reactant or product is allowed to escape and the total concentration of the reaction mixture remains constant. If any of the reactants or products manage to escape, the reaction will no longer be in equilibrium.

Q104. Which of the following is a cycloalkane?

• A. C6H14
• B. C6H12✓
• C. C6H10
• D. C6H0

Explanation: C6H12 follows the formula CnH2n, which is the general formula for cycloalkanes. Cycloalkanes have two Hydrogen atoms less than their parent alkane. Cycloalkanes share the same general formula with alkenes.

Q105. The uncertainty principle can be expressed as:

• A. Apax-h
• B. AEA-h
• C. both (a) and (b)✓
• D. None

Explanation: The uncertainty principle arises from the wave-particle duality.A quite accurate measurement of one observable involves a relatively large uncertainty in the measurement of the otherIt is expressed in terms of a particle's momentum and position, i.e.p x=h and can alternatively be expressed in terms of Energy and time, i.e., E T=h, so option C is correct.

Q106. Reason for alkali metals to be soft is that

• A. They are less metallic in nature
• B. There is only one valency
• C. They do not having tightly packed structures✓
• D. They have high IE

Explanation: Alkali metals are soft because of their large atomic size and single valence electron, leading to weaker metallic bonds between atoms. This results in a less tightly packed structure and softer texture. The other options are incorrect because they do not address the specific atomic properties that contribute to the softness of alkali metals.

Q107. If water samples are taken from a sea, river, cloud, lake, or snow, they will be found to contain hydrogen and oxygen in the ratio of 1:8 by weight. This indicates the law of:

• A. Definite proportion✓
• B. Multiple proportion
• C. Reciprocal proportion
• D. None of above

Explanation: The law of constant composition states that a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source or method of preparation. A sample of H₂O from any source will have hydrogen and oxygen in a ratio of 1:8 by mass. (Mass ratio in H2O = 2:16 = 1:8).

Q108. If the pressure and temperature (k) of two liters of CO2 are doubled the volume of CO2 would become:

• A. 5 liters
• B. 4 liters
• C. 8 liters
• D. 2 liters✓

Explanation: As PV=nRT or V =nRT/PUsing P’=2P and T’=2T, we getV’= 2nRT/2PV’= nRT/PV’= VSo , the volume will be 2 litres.

Q109. How many atoms are contained in one mole of Ca(OH)2?

• A. 5 x 6.02 x 1023 atoms✓
• B. 30 x 6.02 x1023
• C. 3x x 6.02 x 1023
• D. 6 x 6.02 x 1023

Explanation: The number of atoms in one mole of substance can be calculated byNo. Of atoms = atomicity X Avogadro's no.As a molecule of Ca(OH)2 contains 5 atoms (1Ca, 2O, and 2H), its atomicity is 5.So number of atoms in one mole of Ca(OH)2 will be 5 x 6.022 x 1023 atoms.

Q110. Lowering in vapour pressure is the highest for:

• A. 0.2 M urea
• B. 0.1 M Glucose
• C. 0.1 M MgSO4
• D. 0.1 M BaCl2✓

Explanation: The higher the vanthoff factor, the greater the lowering of vapor pressure. The highest van der hoff factor is for BaCl2On dissociation, it gives 3 moles of ions (2 chloride and one barium). So the highest lowering of vapor pressure will be for BaCl2.

Q111. The oxidation number of chlorine in Ca(ClO3)2

• A. -1
• B. +3
• C. +5✓
• D. -6

Explanation: This has to be calculatedThe oxidation state of Ca is +2, and oxygen is -2, so:(+2) + (2x) + (6 x -2) = 0; calculating this gives x = +5

Q112. Fast neutrons can be slowed down by collisions with:

• A. Electrons
• B. Protons✓
• C. Phonons
• D. Photons

Explanation: A nuclear reactor is a device in which nuclear reactions are initiated,maintained,and controlled.It works on the principle of controlled chain reactions and provides energy at a constant rate.The moderator in a nuclear reactor slows down fast-moving secondary neutrons produced during fission.These moderators are rich in protons.When fast-moving neutrons collide head-on with the protons of moderator substances,their energies are interchanged, and thus the neutrons are slowed down.

Q113. CH3CH2l reacts with dry Ag2O to give

• A. Diethyl ether
• B. Ethane
• C. Ethanal
• D. Ethanol✓

Explanation: When CH3CH2l reacts with dry Ag2O, the correct product formed is ethanol. This reaction involves the substitution of the iodine atom in the compound with a hydroxyl group from Ag2O, leading to the formation of ethanol. The other options, diethyl ether, ethane, and ethanal, are not the products formed in this specific reaction.

Q114. The constancy of the e/m ratio of electrons shows that:

• A. Electron mass is 1/87th of proton
• B. Electron are universal particles of all matter✓
• C. Electrons are produced in discharge
• D. None of the above

Explanation: The constancy of the e/m ratio for electrons despite variations in the gas present in the discharge tube or in the material of the cathode shows that electrons are universal constituent particles. Electrons are present in all elements in their standard state, and the individual properties of electrons are the same for every element.

Q115. Which one of the following acids has the highest PH value?

• A. HCl(aq)
• B. HNO3 (aq)
• C. HF (aq)✓
• D. H2SO4(aq)

Explanation: As the pH of an acid increases, the strength of the acid decreases. Acid strength describes the tendency of an acid to dissociate (split into its ionic constituents in an aqueous solution). HF has the highest pH (about 3). It is a weak acid as it fails to completely dissociate in aqueous solution as the bond between H+ and F- is very strong since F is highly electronegative. HCl has a very low pH (close to 1). HNO3 also has a Low pH around 1.6. H2SO4 pH is around 2.3. HCl has the lowest pH as it is the strongest acid. It completely dissociates in an aqueous solution.

Q116. When a wave is reflected while entering from rarer medium to a denser medium, then at the boundary, the reflected wave undergoes a phase change of

• A. 0°
• B. 180°✓
• C. 90°
• D. 45°

Explanation: When the transverse wave travels from the rarer medium to the denser medium, it gets reflected from the denser medium, where a phase change of π radian or 1800 occurs.

Q117. The magnitude of the resultant of two forces is F. The magnitude of each force id F. The angle between the forces must be:

• A. 20°
• B. 60°
• C. 120°✓
• D. 45°

Explanation: If we know the magnitude of two forces and the angle between them, we can find the magnitude of the resultant force by applying the following formula:R=√A2+B2+2ABcosθ​ Given that the two forces are of equal magnitude =F and the resultant of these forces =F F=√F2+F2+2F2cosθF2=2F2(1+cosθ)cosθ=−1/2θ=120∘Final answer:120∘

Q118. The maximum KE of an emmitted photoelectrons depends on:

• A. Intensity of the incident light
• B. Frequency of the incident light✓
• C. Temperature of the photosensitive surface
• D. None of the above

Explanation: The maximum KE of emitted photoelectrons depends on the frequency of incident lightThis can be represented by the photoelectric equationEk = hf + wWhere Ek is the maximum kinetic energy of emitted photoelectrons, h is the Planck's constant, f is the frequency of incident light and w is the work functionFor a given material, w remains constant, so the maximum kinetic energy is dependent on the frequency.

Q119. The half-life of a radioactive source is 2.3 days. Its decay constant per day will be:

• A. 0.1
• B. 0.2
• C. 0.3✓
• D. 2.3

Explanation: T1/2 = 0.693/λ.Where T1/2= half life and λ= decay constant When half life= 2.3 daysSo λ = 0.693/T1/2= 0.693/2.3=0.30 per day

Q120. The first law of thermodynamics can be expressed mathematically as:

• A. Δθ = Δu + Δw✓
• B. Δθ = Δu
• C. Δθ = Δw
• D. None

Explanation: First law of thermodynamics states “ energy can neither be created nor destroyed, it can only be altered/changed into different forms”. Δθ= Δu + Δw is one of the mathematical expression for first law of thermodynamics which explains that heat supplied to the system(Δθ) is equal to change in internal energy of the system(Δu) plus work done by the system on the surrounding(Δw).

Q121. The frequency of the fundamental mode of a string stretched by a tension / and having mass m and length l is given by:

• A. f = ½ √T/ml
• B. f = 1/2l √T/m✓
• C. f = 1/2l√T/m
• D. f = 1/2√T/m

Explanation: The fundamental frequency of a string stretched by tension T, with mass m and length l, is given by the formula f = 1/2l √T/m. This formula considers the tension's impact on wave speed and the string's physical properties. Option B correctly represents this formula. Option A misplaces the square root and factors, leading to an incorrect expression. Option C closely resembles the correct formula but contains a typographical error, which makes it incorrect. Option D omits the factor of length, which is critical in determining the frequency.

Q122. What will be the effect on the speed of transverse waves on a string if the tension in the string remains constant but the diameter of the string becomes double?

• A. Remains constant
• B. Becomes Half✓
• C. Becomes double
• D. Becomes four times

Explanation: As v=sqrt(T/d),Where T is tension and d is linear density of the stringAlso,d=m/l(mass per unit length)And mass is directly proportional to Area which is directly proportional to square of diameterThus,doubling diameter quadruples the linear density.As v=1/sqrt(d),The speed will be cut in half by doubling diameter.

Q123. A laser is a device that can produce:

• A. Intense beam of light
• B. Coherent beam of light
• C. Monochromatic beam of light
• D. All of the above✓

Explanation: A laser is a device that produces an intense, coherent, and monochromatic beam (made of rays) of light. Laser light is different from typical light sources as the beam produced is coherent and monochromatic. Coherent refers to the fact that all the light rays in the beam are in phase, i.e., the troughs of all the light waves in the beam line up together, as do all the crests. Laser light is monochromatic, which means all of the light produced by the laser is of a single wavelength.

Q124. A particle is moving in a circle of radius r with a constant angular speed . Its acceleration directed towards the center of the circle is:

• A. w/r
• B. w2/r
• C. w2r✓
• D. wr2

Explanation: The formula for angular acceleration is a= = w2r RCentripetal acceleration = V2/r, whereby V=rW, thus (rW)2 / r is = w2 r

Q125. A string passes over a smooth pulley and carries a 3kg mass at one end and a 5kg mass at the other end. The acceleration of the masses is:

• A. 2.45 ms-2✓
• B. 0.25 ms-2
• C. 4.9 ms-2
• D. 2.8 ms-2

Explanation: F=ma F is resultant force Force by 3 kg mass is 3 x 9.81 = 29.43 N BY 5 kg mass is 5 x 9.81 = 49.05 NThe resultant force is 49.05-29.43 = 19.62N19.62/8 (total mass ) =2.45 ms^-2

Q126. Rest mass energy of an electron is:

• A. 0.511 MeV✓
• B. 1 MeV
• C. 8.0x10 J
• D. None of the above

Explanation: Eo=moc^2Where,c2= velocity of light which is 3×10^8 m/smo=rest mass of an electron which is 9.11×10−31 kgEo=rest mass energyPut value of rest mass of an electron and velocity of light in above equation,We get,Eo=9.11×10−31 × (3×10^8)^2Solve this we get,Eo=8.91×10^−14 JWe can convert joule into eV, as our options are also in eV.We know that, 1J=1.6×10−19 eVEo= (8.91×10^−14) / (1.6×10^−19 eV)Eo =0.511MeV

Q127. As compared to a stationary clock, a moving dock clicks: rate as stationary clicks

• A. Slower✓
• B. Faster
• C. Same
• D. Clicks negative time

Explanation: According to Einstein’s Special Theory of Relativity, Time for a moving reference frame actually slows down compared to a “stationary” observer. This works in principle no matter what kind of clock is used, e.g., a wrist watch, crystal oscillator, atomic clock, an hourglass filled with sand, or even a clock made from bouncing light in a mirror setup (which served as Einstein’s original thought experiment). All of this is possible because time itself slows, regardless of how it is measured. According to Einstein’s theory, the amount that time slows is more pronounced the faster an object travels through space (especially as its velocity gets closer to the speed of light); however, at typical speeds encountered in our everyday lives, there is essentially no change in time due to Relativity. For clocks that move at a constant speed, the time change (time dilation) is constant, whereas when clocks are being accelerated (whether linearly or in a gravitational field), the amount of time dilation is governed by Einstein’s General Theory of Relativity. Both Einstein’s Special Theory of Relativity and General Theory of Relativity have been confirmed in every single experiment performed (within the margins of error), except they aren’t compatible with Quantum Mechanics.

Q128. The net change in entropy in the Carnot cycle is:

• A. Zero✓
• B. Positive
• C. Negative
• D. None of the above

Explanation: The Carnot Cycle is a thermodynamic cycle that consists of four subsequent reversible processes: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression.Entropy does not change during adiabatic processes because dQ is 0.

Q129. Which of the following has the high energy photon?

• A. Visible light
• B. X-rays
• C. Ultraviolet light
• D. γ-rays✓

Explanation: Gamma rays have the highest energy because they are at the extreme end of the electromagnetic spectrum, characterized by very short wavelengths and high frequencies. Visible light, ultraviolet light, and X-rays all have lower energy levels compared to gamma rays. Visible light has the least energy among the options, followed by ultraviolet light, then X-rays, with gamma rays having the most energy.

Q130. Two boats moving parallel in the same direction:

• A. Will be pulled towards each other✓
• B. Will drift apart from each other
• C. Will have no effect on each other
• D. Will experience random motion

Explanation: As the speed of water between the ships is greater than outside them, pressure between them gets reduced, and pressure outside is greater, so the excess pressure pushes the ships closer to each other, therefore they get attracted to each other and are pulled towards each other.

Q131. A well-stoppered thermos flask containing some ice cubes is an example of:

• A. closed system
• B. open system
• C. isolated system✓
• D. None of the above

Explanation: Thermoflask will not allow the exchange of matter and energy with the surrounding environment. Hence, it is an example of an isolated system.

Q132. Two parallel wires are carrying current in opposite directions. These two wires

• A. will attract each other
• B. will repel each other✓
• C. will have no effect on each other
• D. None of the above

Explanation: If two parallel wires carry current in opposite directions, they repel each other, whereas if two parallel wires carry current in the same direction, they attract each other.

Q133. The applied force that the solid can withstand without breaking is called:

• A. Stiffness of solids
• B. Strength of solid✓
• C. Ductility of solids
• D. Toughness of solid

Explanation: Strength measures how much stress can be applied to an element before it deforms permanently or fractures.

Q134. As the temperature of the black body increases, the wavelength of maximum intensity radiation increases:

• A. will shift towards the longer wavelength
• B. will shift towards the shorter wavelength✓
• C. will not change
• D. None of these

Explanation: As the temperature of the blackbody increases, the peak wavelength decreases (Wien's Law). The intensity (or flux) at all wavelengths increases as the temperature of the blackbody increases.

Q135. The decay of one radioactive atom per second is equal to

• A. one Becquerel
• B. One curie✓
• C. One-half life
• D. None of above

Explanation: One becquerel is the quantity of a radioactive element in which there is one atomic disintegration per second.

Q136. If a shell explodes in the air, its fragments fly in different directions. The total momentum of the fragments

• A. Increases
• B. Decreases
• C. Remains constant✓
• D. None of the above

Explanation: Initially the shell will be stationary and hence have zero momentum. After explosion the fragments of shell will fly apart in different directions and the sum of their momenta will also be equal to zero so as to obey Law of conservation of momentum.The law of conservation of momentum states that the total linear momentum of an isolated system remains constant.Since the momentum before and after are both zero, options A and B are wrong (as they talk about an increase or decrease in momentum).Option C says it remains constant, which is the correct answer.

Q137. IF a material particle starts motion with speed equal to the speed of light, then mass of the moving particle will:

• A. Remain constant
• B. Become zero
• C. Become equal to rest mass of particle
• D. Become infinite✓

Explanation: Using the formula for mass dilationWhen an object travels at v = c, the factor becomes equal to zero.Dividing mo by zero leads to mass becoming equal to infinity.

Q138. The range of the projectile is the same for two angles which are mutually:

• A. Orthogonal
• B. Supplementary
• C. Complementary✓
• D. Sum is 450

Explanation: Complementary angles are angles that add up to 90 degrees (e.g., 30 degrees and 60 degrees). In the context of projectile motion, if you launch a projectile at two complementary angles, their ranges will be the same. This is because: sin(180∘−2θ). This relationship holds true due to the properties of the sine function.

Q139. The vectoral form of centripetal force is:

• A. Fc = mv2/r
• B. Fc = (mv2/r)r̂✓
• C. Fc = (mv2/r2)r̂
• D. Fc = (mv2/r2)γ

Explanation: Magnitude of centripetal force Fc=mv2/rFor vector form, we multiply it with unit vector ^r to get Fc = (mv)2/r)^γ

Q140. A 50-m coil carries a current of 2 amperes. The energy stored in a magnetic field is:

• A. 10 joule
• B. 0.1 joule✓
• C. 0.01 joule
• D. 1.0 joule

Explanation: Using the formula for energy stored in magnetic field of a coil (E = ½ × L × I²)E = ½ × L × I² E = ½ × (50 × 10-3) × (2)² = 0.1 J

Q141. A body of mass 1 kg is suspended from a balance in the elevator, which is accelerating downward with an acceleration of 4ms-1 the reading of the balance will be:

• A. 9.8 N
• B. 13.8 N
• C. 5.8 N✓
• D. Zero

Explanation: Reading = mg - ma = (1)(9.8) - (1)(4)=9.8 - 4=5.8N

Q142. The radio waves of constant amplitude are called:

• A. Modulated waves
• B. Carrier waves✓
• C. Standing waves
• D. Rectified waves

Explanation: Such waveforms are used in modulation. Modulation is the process of converting data into radio waves by adding information to an electronic or optical carrier signal. A carrier wave is the continuous electromagnetic radiation of constant amplitude and frequency that is given out by a transmitter.

Q143. The resolving power of the lens can be improved by using

• A. Lens of short focal length
• B. Lens of large focal length
• C. Light of short wavelength✓
• D. Light of large wavelength

Explanation: Resolution depends on the wavelength of the light source. The smaller the wavelength, the greater the resolution. Hence, option D is wrong, and option C is the correct answer here.It is independent of focal length, so options A and B are wrong.

Q144. If the length of second pendulum becomes four times, then its time period will become:

• A. Four times
• B. Two times✓
• C. Half
• D. one fourth

Explanation: By understanding the relationship between the length of a pendulum and its time period, we can deduce that if the length becomes four times, the time period will become two times. This is because the time period is proportional to the square root of the length.

Q145. A close surface contains equal and opposite charges. The net electric flux through the close surface is

• A. maximum
• B. minimum
• C. Zero✓
• D. positive as well as negative

Explanation: The surface has an equal number of positive and negative charges, so the net charge will be zero. Guass’s law suggests that Ф = net charge / ∈₀, by using Q = 0, then Ф = 0. Hence, C is the correct option.

Q146. Critical angle of a medium depends upon the:

• A. Speed of light
• B. wavelength of light
• C. Refractive index of the medium✓
• D. intensity of light

Explanation: The critical angle is the angle of incidence, which corresponds to an angle of refraction of 90 degrees when light travels from a denser to a rarer medium.

Q147. The phase change of 180 is equivalent to a path difference:

• A. λ/2✓
• B. λ
• C. 2λ
• D. 4λ

Explanation: A phase change of 180 degrees is equivalent to a path difference of λ/2. This is because a full cycle (360 degrees) corresponds to a path difference of one full wavelength (λ). Therefore, half of that phase change (180 degrees) corresponds to half a wavelength path difference (λ/2), which is the correct answer. Option B (λ) is incorrect because it represents a full wavelength path difference, not half. Option C (2λ) and Option D (4λ) are incorrect because they represent multiple full wavelength path differences, corresponding to phase changes far exceeding 180 degrees.

Q148. The unit of conductance is

• A. Ohm
• B. Ohm-meter-1
• C. Ohm - meter
• D. mho✓

Explanation: The SI unit for conductance is siemen or mho. This is also written as 1/ohm or ohm-1. Ohm is the unit of resistance while ohm-meter is the unit of electrical resistivity.

Q149. At what place will the motion of the bob of the simple pendulum be the slowest?

• A. At the poles of the Earth
• B. At the equator of the Earth✓
• C. Anywhere on the surface of the Earth
• D. None of these

Explanation: The value of “g” is lowest at the equator. As T = 2π √L/g, so the Time period will be maximum hence the it would take more time to complete one oscillation.

Q150. If the resultant of two vectors each of magnitude A is the ,angle between the vectors will be:

• A. 30°
• B. 45°
• C. 60°
• D. 120°✓

Explanation: It is given that two vectors are equal in magnitude i.e. if A and B are two vectors then ∣A∣=∣B∣. It is also mentioned that the magnitude of resultant is equal to the magnitude of either of them i.e. ∣A∣=∣B∣=∣A+B∣…… Eq(1)

Q151. The current gain of a transistor having a collector current of 10 mA and a base current of 40 A is:

• A. 2.5
• B. 25
• C. 250✓
• D. 2500

Explanation: Current gain is the ratio of the change in the collector current to the change in the emitter current in a transistor. Mathematically α=△Ic/△Ie. Current gain = 1X10 -3 / 4X10 -6 =250

Q152. LASER light is the result of

• A. Spontaneous emission
• B. Ordinary emission
• C. Absorption of radiation
• D. Stimulated emission✓

Explanation: Laser stands for Light Amplification by Stimulated Emission of Radiation. Laser light utilizes stimulated emission. Stimulated emission requires the presence of a photon. An “incoming” photon stimulates a molecule in an excited state to decay to the ground state by emitting a photon. The stimulated photons travel in the same direction as the incoming photon. As a result a coherent, monochromatic and intense beam of laser light is created. For stimulated emission to be the dominant process, the excited state population must be larger than the lower state population. This is achieved by excitation of the lasing atoms or molecules - this is called PUMPING.

Q153. If there are coplanar forces acting on a body to keep it in equilibrium, then these forces are:

• A. Concurrent✓
• B. Non-concurrent
• C. Parallel
• D. Anti-parallel

Explanation: “A group of forces acting on an object is called a coplanar system of forces if the line of action of all the forces lies in the same plane.”A coplanar force system is considered a concurrent coplanar force system if the line of action of all the forces passes through the same point. For the given case of three forces, when three or more coplanar forces are acting at a point and the vector diagram closes, there is no resultant. The forces acting at the point are in equilibrium. When three or more coplanar forces are acting at a point and the vector diagram closes, there is no resultant. The forces acting at the point are in equilibrium.

Q154. The dimensions of angular acceleration are:

• A. T-2✓
• B. LT-2
• C. LT-1
• D. M1T-2

Explanation: Angular acceleration (α) is defined as the rate of change of angular velocity (ω) with respect to time (t). Therefore, α = Δω/Δt. The dimension of angular velocity is T-1, so when divided by time (T), the dimension of angular acceleration becomes T-2. This is why the correct answer is T-2.Option B (LT-2) is incorrect because it describes linear acceleration, which involves change in linear velocity rather than angular velocity. Option C (LT-1) is incorrect as it describes velocity, which is a linear measure, not angular. Option D (M1T-2) is incorrect since it is the dimension of force, not relevant to angular acceleration.

Q155. The resistance of the three arms of the balanced wheat stone bridge is 50 ohms. The resistance in the 4 ohm range is:

• A. 25 ohm
• B. 50 ohm✓
• C. 75 ohm
• D. 100 ohm

Explanation: In a balanced Wheatstone bridge, the ratio of the resistances in one arm is equal to the ratio of the resistances in the other arm, expressed as X = (R * Q) / P. With all three known resistances being 50 ohms, the unknown resistance X also calculates to be 50 ohms, thereby maintaining the balance. The other options do not satisfy this relationship and would unbalance the bridge.

Q156. Which of the following is/are conservative fields:

• A. Gravitational
• B. Electric field
• C. Magnetic field
• D. All the above✓

Explanation: A conservative field is a type of vector field in physics where the work done by a force in moving an object from one point to another is independent of the path taken. In other words, it depends only on the initial and final positions of the object. A. Gravitational field is conservative because the work done in moving an object from one position to another depends only on the initial and final positions, not the path taken. B. Electric field is conservative for the same reason as the gravitational field. The work done by an electric field in moving a charged particle depends only on the initial and final positions. C. Magnetic field is not a conservative field. The work done by a magnetic field on a charged particle depends on the path taken, not just the initial and final positions. So, option D, "All," is correct because gravitational and electric fields are conservative, while the magnetic field is not.

Q157. Newton's rings are formed due to:

• A. Diffraction of light
• B. Interference of light✓
• C. Polarisation of light
• D. Reflection of light

Explanation: Newton's rings are formed due to the interference of light. When a plano-convex lens is placed on a flat glass surface, a thin film of air is created between them. Light reflects off both the top and bottom surfaces of this air film. The two reflected light waves can constructively and destructively interfere with each other, depending on the thickness of the air film at various points, resulting in the characteristic pattern of concentric rings. Diffraction, polarisation, and simple reflection do not lead to the specific pattern seen in Newton's rings, making interference the correct explanation.

Q158. The number of photoelectrons emitted per second from the metal surface depends upon

• A. Intensity of light✓
• B. Frequency of light
• C. Wavelength of light
• D. Speed of light

Explanation: According to Planck's quantum theory, the intensity of the incident beam is directly related to the number of photons in the beam. If the intensity of the beam increases, the number of photons will also increase. As the number of photons incident on the metal surface increases, the number of photoelectrons emitted from the metal will also increase.

Q159. The process in which heat neither enters nor leaves the system but still changes the temperature of the system is

• A. Isobaric process
• B. Isothermal process
• C. Adiabatic process✓
• D. Isochor process

Explanation: Adiabatic is a process in which heat neither enters nor leaves a system, but the temperature of the system still changes.

Q160. The transition from n = 4,5,6,.......... To n+3 in hydrogen spectrum gives

• A. Balmer series
• B. Lyman series
• C. Paschen series✓
• D. Pfund series

Explanation: When an electron transitions from a higher energy state to a lower energy state, it releases electromagnetic radiation that falls into certain series. The series are determined by what level of n the e transitions to, such that:Transitions ending in n = 1 fall into the Layman series, while transitions ending in n = 2 fall into the Balmar series.Those transitions that end in n = 3 fall into the Paschen series.

Q161. The applied force which the solid can withstand without breaking is called

• A. Stiffness of solids
• B. Strength of solid✓
• C. Ductility of solids
• D. Toughness of solid

Explanation: Strength measures how much stress can be applied to an element before it deforms permanently or fractures.

Q162. If the moveable mirror is displaced through distance of 0.05 mm, 200 fringes are observed shifted. The wavelength of light used is:

• A. 5x100
• B. 5x10m
• C. 500 nm✓
• D. 50mm

Explanation: This question deals with a Michaelson interferometer. The Michelson interferometer produces interference fringes by splitting a beam of light so that one beam strikes a fixed mirror and the other a movable mirror. When the reflected beams are brought back together, an interference pattern results.For a Michaelson interferometer:nλ=2Δxλ = 2Δx/nλ = 2* 0.05/200 = 0.0005 mm or 5x10-4 mm1 mm = 1x10 +6 nm5x10-4 mm = 5x10 +2 nm or 500 nm

Q163. The resultant of a 6N force and an 8N force acting at right angles to each other is of the magnitude:

• A. 14 N
• B. 2N
• C. 10N✓
• D. 48 N

Explanation: When two forces are acting at right angles to each other, the resultant can be calculated by using the Pythagorean Theorem.One of the forces represents the base (B) of a right-angled triangle, and the other force represents the perpendicular (P). The result of the forces is the hypotenuse (H).Acc to Pythagoras' theroem, H2= P2+ B2H2= 6X6 + 8X8H2= 36+64H2=100Taking sq root, H=10N which is the resultant.

Q164. An important site for formation of glycoproteins and glycolipids is

• A. Vacuole
• B. Golgi apparatus✓
• C. Plastid
• D. Lysosome

Explanation: The correct answer is the Golgi apparatus. This organelle is key in modifying, sorting, and packaging proteins and lipids for secretion or use within the cell. It is specifically involved in the formation of glycoproteins and glycolipids by attaching carbohydrate and lipid moieties to proteins and lipids. In contrast, vacuoles are for storage, plastids are primarily for photosynthesis and pigment storage, and lysosomes are involved in the breakdown of cellular waste.

Q165. Which one of the following is not considered as a part of the endomembrane system?

• A. Golgi complex
• B. Peroxisome✓
• C. Vacuole
• D. Lysosome

Explanation: The correct answer is Peroxisome. Peroxisomes are not part of the endomembrane system because their functions are not coordinated with the other components, such as the endoplasmic reticulum, Golgi complex, lysosomes, and vacuoles. These organelles work together in processes like protein synthesis, modification, and transport. On the other hand, peroxisomes operate independently to carry out specific tasks like lipid metabolism and detoxification.The Golgi complex, vacuole, and lysosome are all components of the endomembrane system, each contributing to the processing and transport of cellular materials.

Q166. The figure below shows the structure of a mitochondrion with its four parts labelled A, B, C and D. Select the part correctly matched with its function.

• A. A (outer membrane) – regulates molecule passage
• B. B (inner membrane) – forms infoldings called cristae✓
• C. C (crista) – site of Glycolysis.
• D. D (matrix) – site of Anaerobic fermentation.

Explanation: The correct answer is B (inner membrane) – forms infoldings called cristae. The inner membrane of the mitochondrion is folded into cristae, which increase the surface area and allow for efficient ATP production via the electron transport chain and ATP synthase. Option A is incorrect because the outer membrane does not give rise to the inner membrane; instead, it serves as a protective barrier. Option C is incorrect as cristae are not associated with possessing DNA; they are associated with ATP synthesis. Option D is incorrect because while the matrix is the site of the citric acid cycle, the respiratory chain enzymes are actually located in the inner membrane.

Q167. The plasma membrane consists mainly of:

• A. Phospholipids embedded in a protein bilayer
• B. Proteins embedded in a phospholipid bilayer✓
• C. Proteins embedded in a polymer of glucose molecules
• D. Proteins embedded in a carbohydrate bilayer

Explanation: Plasma membrane consists of lipids (20-­40%), proteins (60­-80%), carbohydrates (1-­5%) and water . Lipid molecules possess both hydrophobic and hydrophilic ends and are thus arranged in the form of lipid bilayer. The most common lipids of the bilayer are phospholipids. Protein molecules occur at places both inside (intrinsic proteins) and on the outer side (extrinsic proteins) of the phospholipid bilayer.

Q168. The main area of various types of activities in a cell is the:

• A. Plasma membrane
• B. Mitochondrion
• C. Cytoplasm✓
• D. Nucleus

Explanation: The correct answer is Cytoplasm. The cytoplasm is the main area of various cellular activities because it houses the organelles and provides the medium where many metabolic processes occur, such as glycolysis, protein synthesis, and intracellular transport. The plasma membrane is involved in protecting the cell and regulating what enters and exits, but it is not the site of intracellular activities. The mitochondrion is crucial for energy production, but it is just one of the many organelles within the cytoplasm. The nucleus stores genetic information and controls activities through gene expression, but it is not the site where most cellular processes take place.

Q169. Which one of the following has its own DNA?

• A. Mitochondria✓
• B. Dictyosome
• C. Lysosome
• D. Peroxisome

Explanation: Mitochondria are the only organelles among the options listed that contain their own DNA, which is crucial for their role in energy production. This DNA allows them to produce some of the proteins needed for their functions independently from the cell's nuclear DNA. In contrast, dictyosomes, lysosomes, and peroxisomes are all organelles that do not contain their own genetic material. Dictyosomes function in the modification and packaging of proteins, lysosomes are involved in the digestion of cellular waste, and peroxisomes play roles in lipid metabolism and detoxification. Thus, mitochondria stand out because of their unique genetic capability, which is essential for their energy-producing activities.

Q170. The equilibrium constant for a reaction N2 (g)+O2 ------ 2NO is 4 x 10 at 2000 k in the presence of a catalyst. Equilibrium is attained 10 times faster. The equilibrium constant in the presence of a catalyst at 2000 k

• A. 10×10
• B. 4x10
• C. 40 x 10✓
• D. 4x10

Explanation: The equilibrium constant for a reaction remains constant at a specific temperature, regardless of the presence of a catalyst. In this case, the equilibrium constant remains at 4 x 10 even with the catalyst present. Option C is correct because the constant does not change. Options A, B, and D are incorrect because they erroneously suggest a change in the equilibrium constant due to the catalyst.