Balochistan Mdcat Mock Paper 5 — Solved Past Paper with Answers

Q1. Select the nearest correct meaning of the word given.Invidious

• A. Unbreakable
• B. Interesting
• C. Unpleasant✓
• D. Fair

Explanation: "Invidious" means (of an action or situation) likely to arouse or incur resentment or anger in others. This is closest in meaning to "unpleasant" which refers to causing discomfort, unhappiness, or revulsion; disagreeable (something that is likely to arouse or incur resentment or anger in others).

Q2. Choose the correct option: Knowledge and wisdom _ no time for connection.

• A. Has
• B. Have✓
• C. Had
• D. Are

Explanation: The context of the sentence firstly requires a verb that satisfies the need to indicate the possession of "no time for connection" by "Knowledge and wisdom." Therefore the verb forms "is/am/are" which indicate "being" are not suitable here - eliminating Option D. Moreover, since the need for "no time" is being stated as a universal statement (everlasting) i.e. started in the past and continues to be true in the present, the tense should be present perfect. Hence, the verb form should include the helping verb "Have" as indicated by Option B.

Q3. Identify the errors and choose the correct option:

• A. Guliver travels was written to Swift.
• B. Guliver travels was written at Swift.
• C. Guliver’s Travels was written by Swift.✓
• D. Gulivers’ Travel was written by Swift.

Explanation: Option A and Option B are incorrect since the apostrophe + ‘s’ (‘s) is absent which is needed after the noun “Gulliver” to indicate the possessive nature of the travels (i.e. to indicates that the travels were of Gulliver). Since Gulliver had more than one travel in the story, the word should be “Travels” and not “Travel”. Hence, Option D is incorrect, and Option C is correct.

Q4. Fill in the blank with appropriate article as required._ umbrella is of no avail against a thunderstorm.

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

Explanation: "An" umbrella is of no avail against a thunderstorm. The indefinite article "an" is used in this sentence because it introduces the general concept of an umbrella without specifying a particular umbrella. It implies that any umbrella in general would not be effective against a thunderstorm.

Q5. Select the option which fits appropriately in the blank:The robber broke into the house and _ (tie) the lone occupant with ropes.

• A. Tied✓
• B. Ties
• C. Tie
• D. Tying

Explanation: This is the correct past tense form of the verb "tie." It matches the sequence of events described in the sentence, where the action of tying the lone occupant with ropes occurred after the robber broke into the house.

Q6. Select the option which fits appropriately in the blank:The dog sprang _ him.

• A. On
• B. Upon✓
• C. In
• D. Over

Explanation: 'Upon' is a preposition. up and on; upward so as to get or be on: He climbed upon his horse and rode off. It means the same as on/onto as is usually interchangeable.

Q7. Find an error in the following sentence:Everyone who was injured in the accident were taken to the hospital.

• A. Everyone who was injured
• B. In the accident
• C. Were taken✓
• D. To the hospital

Explanation: The error in the sentence is subject-verb agreement. The correct version should be:"Everyone who was injured in the accident was taken to the hospital."In this case, "everyone" is a singular pronoun, so the verb "was" should also be singular to match the subject.

Q8. Select the option which fits appropriately in the blank:Everyone _ done his or her homework.

• A. Has✓
• B. Have
• C. Had
• D. None

Explanation: This is the correct form. "Has" is used with the indefinite pronoun "everyone," which is singular. In English, indefinite pronouns like "everyone," "somebody," "anybody," etc., are treated as singular subjects and require a singular verb form. Therefore, "has" agrees with "everyone" in number.

Q9. None of them _ able to solve this question.

• A. is
• B. were✓
• C. will
• D. would

Explanation: "None" is often treated as plural when it refers to more than one person or thing, as in this case: "none of them"."Were" is the plural form of the verb "to be" used with plural subjects

Q10. The diagram shows the four types of human teeth. Which teeth are used for cutting rather than grinding food?

• A. 1 and 2✓
• B. 2 and 3
• C. 3 and 4
• D. 4 and 1

Explanation: Most adults have 32 permanent teeth, including eight incisors, four canines, eight premolars, and 12 molars. Incisors and canines are used to cut and chew. Premolars and molars are used for grinding the food.

Q11. A woman with normal colour vision, whose father was red green colour blind, married a red green colour blind man. What is the probability of her born child being red green colour blind?

• A. 1.0
• B. 0.75
• C. 0.50✓
• D. 0.25

Explanation: Males have 1 X chromosome and 1 Y chromosome, and females have 2 X chromosomes. The genes that can give you red-green colour blindness are passed down on the X chromosome.The woman’s father is red-green colour blind. Since the woman got one of her X chromosomes from her father this means that she is a carrier. As it can be seen from the table the probability of having a colourblind child is 0.5%

Q12. In the juxtamedullary nephron, a network of blood capillaries parallel to the loop of Henle is called:

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

Explanation: The correct answer is Vasa Recta. In juxtamedullary nephrons, the vasa recta are specialized capillaries that extend down into the medulla parallel to the loop of Henle. They play a key role in maintaining the concentration gradient necessary for water reabsorption. The other options are incorrect: Netted Capillaries is not a specific term used in renal physiology; Afferent Capillaries refers incorrectly to afferent arterioles, which supply blood to the glomerulus; and Peritubular Capillaries surround the convoluted tubules of cortical nephrons, not the loop of Henle in juxtamedullary nephrons.

Q13. Chlorosis refers to the lack of:

• A. Growth
• B. Chlorophyll✓
• C. Yellowing of leaf margin
• D. Width of leaf

Explanation: By definition, chlorosis is a condition in which leaves become pale or yellow due to lack of chlorophyll so option B is correct, making the rest of the options incorrect.

Q14. Amniocentesis is performed between:

• A. 16th and 18th week of gestation✓
• B. 1st and 2nd week of gestation
• C. 30th and 32nd week of gestation
• D. 37th and 38th week of gestation
• E. After the delivery of the baby

Explanation: Amniocentesis is a prenatal diagnostic procedure performed between the 16th and 18th weeks of gestation. This timing ensures there is enough amniotic fluid for sampling, which is critical for analyzing the genetic health of the fetus. Performing amniocentesis earlier, such as in the 1st or 2nd week, is not feasible due to insufficient amniotic fluid. Later stages, such as the 30th week onwards, are not ideal for this procedure as the primary aim is to diagnose potential issues earlier in the pregnancy. Conducting this procedure post-delivery is impossible as it is specifically a prenatal test.

Q15. Male and female sea urchins release their sperm and eggs Into the water where fertilization takes place. How can their reproduction be described?

• A. Asexual reproduction which results in genetically dissimilar offspring
• B. Asexual reproductlon whlch results In genetically identical offspring
• C. Sexual reproduction which results in genetically dissimilar offspring✓
• D. Sexual reproduction which results in genetically identical offspring

Explanation: A type of reproduction in which gametes join to form a new offspring is called sexual reproduction. Sexual reproduction involves the mixing of two genetic materials resulting in genetically dissimilar offspring.

Q16. The diagram shows some of the organs of the human body. In which organs does the digestion of carbohydrates take place?

• A. P and Q
• B. P and R✓
• C. Q and R
• D. Q and S

Explanation: Digestion of carbohydrates takes place in the mouth (P) with the help of salivary amylase which converts starch to maltose. It also occurs in the intestine(R) with the help of pancreatic amylase, which yields disaccharides from starch by digesting the glycosidic bonds. The disaccharides produced (maltose, maltotriose, and α-dextrins) are all converted to glucose by brush border enzymes. Q is the stomach where protein digestion starts. S is the liver where digestion does not take place, although it does aid in digestion by producing bile and enzymes. So option B is correct (P & R)(Mouth and small intestine).

Q17. Five words are shown below:Labium, Maxillae, Labrum, Mandibles and AntennaeThese words can be used in the spaces P, Q, R, S, and T to complete the sentence below.Cockroaches are omnivorous and can eat any kind of organic matter. They search for their food by their ..P.. Their digestive system is tubular, having a straight slightly coiled digestive tube opening at both the ends. Hence, the digestive system is complete. The mouth lies at the base of the pre-oral cavity which is bounded by the mouth parts, ..Q.. (upper lip), ..R.. (lower lip), mandibles, and maxillae. The ..S.. pick up and bring food to the ..T.. for mastication.

• A. Option A
• B. Option B✓
• C. Option C
• D. Option D

Explanation: Roaches use their antennae to locate food and estimate the distance and height of any obstacles in front of them. The labrum is also known as the upper lip. It consists of a flattened cuticle and helps to hold the food in the correct position when the cockroach feeds. The labium is often called an insect's lower lip. The labium is positioned towards the back of the head and helps hold food in place when the insect feeds. Maxillae are used to hold and manipulate food so that it can be chewed or sliced by the mandibles. The function of mandibles is to grasp, crush, or cut the food (mastication means to grind or crush (food) with or as if with the teeth). Using this information, the only correct option is option B.

Q18. Dietary fibre passes through several structures after leaving the stomach. In which order do the dietary fibres pass through the structures?

• A. Duodenum -> Jejunum -> Ileum -> Rectum -> Colon
• B. Ileum -> Duodenum -> Colon -> Jejunum -> Rectum
• C. Ileum -> Duodenum -> Jejunum ->Rectum -> Colon
• D. Colon -> Duodenum -> Ileum -> Rectum -> Jejunum
• E. Duodenum -> Jejunum -> Ileum -> Colon -> Rectum✓

Explanation: The correct order for dietary fiber passing through the digestive system after leaving the stomach is: duodenum, jejunum, ileum, colon, and finally rectum. This sequence follows the natural progression from the small intestine, where digestion and absorption occur, to the large intestine, where water absorption and feces formation take place. Option E correctly lists this sequence. The other options fail to follow this order, either starting in the middle of the process or misplacing the positions of the colon and rectum.

Q19. In peas, the gene for yellow color (C) is dominant to the gene for green color (c). To determine the genotype of an unknown yellow pea, what kind of pea should you cross with it?

• A. Another unknown green pea
• B. Any genotype
• C. Homozygous dominant
• D. Homozygous recessive (cc)✓

Explanation: A green pea would definitely be homozygous recessive. A is the best option because if the unknown dominant individual is heterozygous, then the offspring of this year's cross will include some recessive individuals. If the unknown is homozygous, then all offspring will be dominant heterozygous. In this way, crossing an unknown dominant phenotype with a recessive individual is the surest way of determining the unknown genotype.

Q20. An embryo of a turtle, mouse, and human show?

• A. Comparative embroyology✓
• B. Distinct differences
• C. Vestigial organs
• D. Analogous structures

Explanation: Comparative embryology is the study of the similarities and differences in the embryos of different species to understand their evolutionary relationships and development. Key insights come from comparing embryonic structures like gill slits and tails, which show evidence of common ancestry, and studying developmental patterns to infer evolutionary history. This field has provided crucial support for evolutionary theory and helps researchers understand fundamental biological processes like gene regulation and morphogenesis.

Q21. Neo-Darwinism was developed in?

• A. Early 1940s✓
• B. Early 1950s
• C. Early 1930s
• D. Early 1960s

Explanation: Neo-Darwinism was introduced by the physiologist Georges Romanes in 1883 and was developed into the Modern Synthesis in 1942 as a gene-centered view of evolution.

Q22. The enzyme which plays an important role in HIV pathogenesis:

• A. RNA polymerase I
• B. DNA polymerase II
• C. Reverse transcriptase I
• D. Reverse transcriptase✓

Explanation: HIV pathogenesis is a condition in which there is a competition between HIV replication and the immune responses of the patient.HIV is a retrovirus. It has an RNA genome. HIV uses reverse transcriptase enzymes to convert its RNA genome to DNA to infect the host cells.

Q23. Which of the following is not isotonic to sea water?

• A. Myxine (Hagfish)
• B. Skates
• C. Sharks
• D. Teleost (Bony Fishes)✓

Explanation: Marine teleosts are hypoosmotic to seawater, so they face osmotic loss of water and diffusional gain of NaCl across the gill.

Q24. Scapula is the bone of:

• A. Skull
• B. Pelvic girdle
• C. Pectoral girdle✓
• D. Vertebral column

Explanation: The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton that connect to the arm on each side. In humans, it consists of the clavicle and scapula. Refer to the image below:

Q25. They are organelles of symbiotic origin:

• A. Nucleolus & Mitochondria
• B. Golgi complex & ER
• C. Chloroplast & Mitochondria✓
• D. Mitochondria & ER

Explanation: Mitochondria and chloroplasts both originated from bacterial endosymbionts and therefore, are organelles of symbiotic origins.

Q26. Which of the following hormones of the pituitary gland regulates the menstrual cycle?

• A. Follicle Stimulating hormone and Estrogen
• B. Luteinizing hormone and Estrogen
• C. Follicle Stimulating hormone and Luteinizing hormone✓
• D. Estrogen and Progesterone

Explanation: Four hormones are primarily active in the menstrual cycle namely; FSH: Secreted by the anterior pituitary gland. In women, FSH helps control the menstrual cycle and stimulates the growth of eggs in the ovaries. LH: Secreted by the anterior pituitary gland. It also triggers the release of an egg from the ovary in the process known as 'ovulation'. (Option C is therefore correct since both; FSH and LH are produced by the pituitary gland)Estrogen: The ovaries, which produce the eggs, are the main source of estrogen from your body. In females, it helps to develop and maintain both the reproductive system and female characteristics, such as the breasts and pubic hair. Estrogen causes the uterine lining to grow and thicken to prepare the uterus for pregnancy. Progesterone: The corpus luteum in the ovaries, and the placenta, after the embedding of the zygote in the uterus lining, tend to release progesterone. The hormone prepares the endometrium lining to receive and nourish a fertilized egg. If pregnancy does not occur, estrogen and progesterone levels decrease. The decrease in progesterone triggers menstruation or shedding of the lining. Once the lining is completely shed, a new menstrual cycle begins.

Q27. How many sperms are produced from fifty secondary spermatocyte?

• A. 200
• B. 100✓
• C. 50
• D. 150

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

Q28. Over eating psychological disorder is called:

• A. Dyspepsia
• B. Septicemia
• C. Anorexia
• D. Bulimia✓

Explanation: Bulimia nervosa is an eating disorder in which a person may eat a lot of food at once and then try to get rid of the food by vomiting, using laxatives, or sometimes over-exercising.

Q29. The first successful surgery of heart was performed by Dr. Ludwig by repairing a wound on which part:

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

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

Q30. The following statement is true for the absorption spectra of photosynthesis:

• A. Chlorophyll a and b have the same absorption spectra.
• B. Chlorophyll a and b have different absorption spectra.✓
• C. Chlorophyll a and carotenoids have the same absorption spectra.
• D. Carotenoids and chlorophyll b have the same absorption spectra.

Explanation: Yes, chlorophyll-a and chlorophyll-b, the two main types of chlorophyll found in photosynthetic organisms, have slightly different absorption spectra. Chlorophyll-a and chlorophyll-b absorb light most efficiently in the blue and red regions of the electromagnetic spectrum, but they have different absorption peaks. While chlorophyll-a is directly involved in the conversion of light energy to chemical energy in the photosystems, chlorophyll-b expands the range of light that can be captured and utilized for photosynthesis.

Q31. The main difference between catalysts and enzymes is:

• A. Enzymes are more specific in action than catalysts
• B. Catalysts are required in larger quantities than enzymes
• C. Catalysts are generally inorganic while enzymes are organic and protein-based✓
• D. Enzymes require specific pH conditions, whereas catalysts do not

Explanation: Enzymes are organic molecules, primarily proteins, whereas most catalysts are inorganic substances.

Q32. Referring to sexual reproduction, humans are:

• A. Hermaphrodites
• B. Vivaparous✓
• C. Oviparous
• D. Self-fertilized

Explanation: The main difference between oviparous and viviparous animals is that oviparous animals do not undergo any embryonic development inside the mother whereas viviparous animals develop into young animals inside the mother. This means oviparous animals lay eggs. These eggs develop and hatch into young individuals.A hermaphrodite is an organism with both male and female genitalia. In sexually reproducing organisms, males have organs that produce male gametes, usually sperm. Sometimes the genders pair off equally, one male for one female. Other times, one male or female will breed with a large group of the other gender.

Q33. Match the hormones listed under column I with their functions listed under the column. Choose the answer which gives the correct combination of the alphabets of the II columns.

• A. A = s, B = r, C = p, D = q✓
• B. A = t, B = p, C = s, D = r
• C. A = s, B = q, C = r, D = t
• D. A = t, B = r, C = p, D = s

Explanation: One of the functions of oxytocin is to stimulate uterine contractions in labor and childbirth, so the correct letter is S for A (A=S), so options B and D are incorrect. Prolactin causes the breasts to grow and make milk during pregnancy and after birth, so the correct letter is R for B (B=R), so option C is also incorrect. LH triggers the release of an egg from the ovary i.e. ovulation. Progesterone helps to prepare the body for pregnancy by stimulating glandular development and the development of new blood vessels. This provides a good environment for implantation by a fertilized egg, so it aids in implantation. So option A is correct.

Q34. Which one of the following represents the changes that occur in the ovary and the uterus approximately every 28 days involving ovulation with the breakdown and loss of the lining of the uterus?

• A. Ovulation
• B. Menstrual cycle✓
• C. Uterine cycle
• D. Embryo formation

Explanation: Changes that occur in females in ovary and uterus every 28 days is collectively referred to as menstrual cycle.

Q35. Testes are structures that produce:

• A. Spores
• B. Sperms✓
• C. Seeds
• D. Ova

Explanation: The testes (or testicles) are critical to the male reproductive system, primarily producing sperm and the hormone testosterone. This makes them essential for both reproduction and secondary sexual characteristics in males. Spores are not relevant to animal reproduction and are associated with fungi and plants. Seeds are a plant reproductive structure, resulting from the fertilization of ovules, while ova are female reproductive cells produced by the ovaries, not the testes.

Q36. Poliomyelitis normally affects the:

• A. Legs
• B. Brain
• C. Spinal cord✓
• D. Both B and C

Explanation: Option A: Legs cannot be the answer as the person's nerve from the spinal cord, which supplies the legs, is affected. Option B: Poliomyelitis does not affect the brain. It affects the spinal cord. Option C: Polio, or poliomyelitis, is a disabling and life-threatening disease caused by the poliovirus. The virus spreads from person to person and can infect a person's spinal cord, causing paralysis (can't move parts of the body). Option D cannot be the answer.

Q37. Based on the peak levels of hormone X, on what day of the cycle is ovulation most likely to occur?

• A. Day 21
• B. Day 14✓
• C. Day 12
• D. Day 25
• E. Day 28

Explanation: Peak of LH hormone occurs at 14th day. So, the ovulation occurs at 14th day.

Q38. Which one of the following types of cell are found in secondary xylem of angiosperms?

• A. Tracheids parenchyma fibres collenchyma but no vessels
• B. Vessels tracheids parenchyma collenchyma but no fibres
• C. Vessels tracheids fibres collenchyma but no parenchyma
• D. Vessels tracheids fibres parenchyma but no collenchyma✓
• E. None of these

Explanation: Option D is the correct answer. Secondary xylem of angiosperms have vessels, tracheids, fibres, parenchyma, but no collenchyma.Conceptual and fact.

Q39. Which of the following conditions is due to a nutritional deficiency?

• A. Hepatitis
• B. Cholera
• C. Malaria
• D. Beriberi✓
• E. Alzheimer's Disease

Explanation: Beriberi is, nutritional disorder caused by a deficiency of thiamin (vitamin B1) and characterized by impairment of the nerves and heart. General symptoms include loss of appetite and overall lassitude, digestive irregularities, and a feeling of numbness and weakness in the limbs and extremities. All other diseases mentioned do not apply.

Q40. Identify the bones in which the connecting joints are freely movable?

• A. Ankle
• B. Wrist
• C. Vertebrae
• D. Elbow
• E. All of the above except vertebrae✓

Explanation: There are six types of freely movable joints. Namely, ball and socket joint, hinge joint, pivot joint, condyloid joint, saddle joint, and gliding joint. The ankle joint is a hinge-type joint. The wrist is a condyloid joint. Joints of the vertebrae are cartilaginous joints that allow gliding. The elbow joint is a hinge joint. Thus, all the options are examples of freely movable joints except vertebrae.

Q41. The optimum pH for the action of pepsin and salivary amylase is

• A. 3.5 and 7.7 respectively
• B. 1.8 and 6.8, respectively✓
• C. 6.8 and 7.4 respectively
• D. 1.8 and 7.4 respectively

Explanation: The stomach has a pH between 1.5 and 3.5 generally, and this is due to the cells in the stomach releasing hydrochloric acid, which is where pepsin is present, so it has a low optimum pH of around 2, so options A and C are incorrect. Saliva has a pH normal range of 6.2-7.6, with 6.7 being the average pH, which means salivary Amylase should have an optimum pH around the same range. Amylase has an optimal pH between 6.4 and 7.0.

Q42. In protein synthesis the initiator tRNA carrying amino acid methionine land on which site of ribosome:

• A. E site
• B. P site✓
• C. A site
• D. C site

Explanation: In protein synthesis, the initiator tRNA molecule carrying chemically modified initial amino acid, methionine (known as N-formyl methionine) binds to a small ribosomal subunit at P-site (peptidyl site) where a peptide bond will form. This binding is controlled by an enzyme called initiation factors (IF1 and IF2).

Q43. Short life cycle is a plant adaptation to survive in:

• A. High temperature
• B. Low temperature✓
• C. High soil pH
• D. Low soil pH

Explanation: Plants growing in low temperatures may suffer from ill effects. To manage low temperatures, they possess well-developed bark for protection and short life cycles. Such plants bring changes in the composition of solutes in the cell to prevent ice crystal formation. The leaves and stems are hardy to withstand low temperatures. Most of them possess scale leaves, and the rate of transpiration is low to retard cooling.

Q44. How many meninges cover the human brain?

• A. 5
• B. 4
• C. 3✓
• D. 2
• E. 1

Explanation: There are three layers of meninges around the brain and spinal cord. The outer layer, the dura mater, is tough, white fibrous connective tissue. The middle layer of meninges is the arachnoid, a thin layer resembling a cobweb with numerous threadlike strands attaching it to the innermost layer.

Q45. Which of the following region in alimentary cannal produces no enzyme?

• A. Oesophagus✓
• B. Duodenum
• C. Stomach
• D. Jejunum

Explanation: The oesophagus does not produce any digestive enzyme; it only transports food to the stomach.

Q46. Digestion of _ starts in oral cavity due to the action of enzyme present in :

• A. Starch.✓
• B. Fatty Acids
• C. Cellulose
• D. Polypeptides

Explanation: Starch digestion begins in the mouth with the help of salivary amylase.

Q47. Food is diverted into the eoesophagus by:

• A. Glottis
• B. Cheeks
• C. Tongue
• D. Epiglottis✓

Explanation: The epiglottis is a flap-like structure located at the base of the tongue. Its primary function is to cover the opening of the trachea (windpipe) during swallowing, preventing food and liquids from entering the airway. Instead, it directs food and liquids into the esophagus, ensuring that they reach the stomach without entering the respiratory system.

Q48. Salivary Amylase begins to digest Starch to shorter polysaccharides and then to:

• A. Glucose
• B. Maltose✓
• C. Sucrose
• D. Lactose

Explanation: Salivary amylase breaks down starch into maltose, a disaccharide made of two glucose units.

Q49. Type of salivary glands found in human oral cavity:

• A. 3✓
• B. 6
• C. 4
• D. 2

Explanation: Humans have three pairs of salivary glands. parotid, submandibular, and sublingual.

Q50. Removal of calcium from freshly collected blood would:

• A. Cause delayed clotting
• B. Prevent clotting✓
• C. Cause immediate clotting
• D. Prevent destruction of hemoglobin.

Explanation: The correct answer is Option B: prevent clotting. Calcium ions play a critical role in the blood clotting process by enabling the conversion of prothrombin to thrombin and fibrinogen to fibrin, which are essential steps in forming a blood clot. Therefore, if calcium is removed from blood, these reactions cannot occur, effectively preventing clot formation. Option A is incorrect because delayed clotting implies that clotting will still occur, which is not the case when calcium is removed. Option C is incorrect because calcium removal will not cause immediate clotting; it will stop clotting altogether. Option D is incorrect because calcium removal does not relate to hemoglobin destruction or preservation.

Q51. The tricuspid valve is found in between:

• A. Sinus venous and right atrium
• B. The right atrium and right ventricle✓
• C. left ventricle and left atrium
• D. left ventricle and aorta.

Explanation: The tricuspid valve is found between the right atrium and the right ventricle.

Q52. Lymph differs from blood in having:

• A. No WBCs
• B. No proteins
• C. No RBCs✓
• D. None of the above

Explanation: The lymph is a whitish fluid which is derived from the interstitial fluid that circulates throughout the lymphatic system. It contains a variety of substance like proteins, glucose, water, salts, fats and white blood cells. It does not have RBCs.

Q53. RBCs do not occur in:

• A. Frog
• B. Cow
• C. Camel
• D. Cockroach✓

Explanation: Cockroaches have an open circulatory system with hemolymph but no RBCs, as oxygen transport is via tracheae.

Q54. Four events in the transmission of nerve impulses across synapses are:I. Depolarisation of the presynaptic membraneII. Propagation of postsynaptic action potentialIII. Reabsorption of the transmitter substanceIV. Release of transmitter substance into the synaptic cleftIn which sequence do these events occur?FIRST -> LAST

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

Explanation: The sequence of transmission of nerve impulses is as follows:1. Depolarisation occurs at the presynaptic terminal.2. This leads to the release of the transmitter substance to the cleft.3. This leads to the depolarization at the postsynaptic membrane.4. Then the transmitter substance is reabsorbed back to the presynaptic membrane.So, from the above summary, it shows that the sequence in the transmission of nerve impulses across synapses is 1, 4, 2, and then 3.

Q55. Goblet cells are:

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

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

Q56. Baroceptors are the sensors in body responsible for determination of:

• A. Blood Glucose
• B. Blood Ammonia
• C. Blood 𝑝H
• D. Blood Pressure✓

Explanation: Baroreceptors are mechanoreceptors located in blood vessels near the heart that provide the brain with information about blood volume and pressure by detecting the level of stretch on vascular walls.

Q57. A decrease in blood pressure/volume will not cause the release of:

• A. Atrial natriuretic factor✓
• B. Aldosterone
• C. ADH
• D. Renin

Explanation: The correct answer is Atrial natriuretic factor (ANF). ANF is secreted by the atria of the heart in response to increased blood volume and pressure, not a decrease. It works to reduce blood volume and pressure by promoting sodium excretion and decreasing the release of aldosterone. On the other hand, Aldosterone, ADH, and Renin are all released in response to a decrease in blood pressure or volume. Aldosterone increases sodium reabsorption, ADH reduces water excretion, and renin triggers the renin-angiotensin-aldosterone system to increase blood pressure.

Q58. The external solution having more concentration than the cell sap is known:

• A. Hypertonic solution✓
• B. Hypotonic solution
• C. Isotonic solution
• D. None of these

Explanation: The correct answer is a hypertonic solution. In osmoregulation, when a cell is placed in a hypertonic solution, the external environment has a higher concentration of solutes compared to the inside of the cell. This concentration difference causes water to move out of the cell through osmosis, leading to a decrease in cell volume and potential plasmolysis. Conversely, a hypotonic solution would cause water to move into the cell, and an isotonic solution would result in no net water movement. None of these is incorrect because the correct term for a solution with higher solute concentration than the cell sap is indeed a hypertonic solution.

Q59. Which kind of therapy was given in 1990 to a four­ year­ girl with Adenosine Deaminase (ADA) enzyme deficiency?

• A. Gene therapy✓
• B. Chemotherapy
• C. Immunotherapy
• D. Radiation therapy

Explanation: Gene therapy is a technique of genetic engineering which involves the replacement of a faulty/disease-causing gene by a normal healthy functional gene. The first clinical ex-vivo gene therapy was given in 1990 to a 4­-year old girl with adenosine deaminase (ADA) enzyme deficiency. This enzyme is very important for the immune system to function and the deficiency of this enzyme can lead to severe combined immune deficiency (SCID).

Q60. Homeostasis is the _

• A. Tendency to change with environmental changes
• B. Tendency to resist change and maintain stability✓
• C. Disturbance in regulatory control
• D. Use of plants and animal extracts in homeopathy

Explanation: Homoeostasis is the regulation, by an organism, of the chemical composition of its body fluids and other aspects of its internal environment so that physiological processes can proceed at optimum rates. It involves monitoring changes in the external and internal environment by means of receptors and adjusting the composition of the body fluids accordingly; excretion and osmoregulation are important in this process. Example of homeostatic regulation are the maintenance of the acid-base balance and body temperature.

Q61. Which of the following does NOT favour the formation of large quantities of dilute urine?

• A. Renin✓
• B. Atrial Natriuretic Factor (ANF)
• C. Alcohol
• D. Caffeine

Explanation: Renin promotes sodium/water retention, reducing dilute urine formation.

Q62. What is correct about myoglobin?

• A. It is an iron-containing protein pigment
• B. It is found in muscle fibers
• C. It stores oxygen
• D. All of these✓

Explanation: Myoglobin is indeed an iron-containing protein pigment, which is what gives muscle tissues their reddish color. It is found in muscle fibers, where it plays a vital role in storing oxygen. This oxygen storage is crucial for muscle function, as it allows for sustained energy production during muscle contraction. Each of the individual options describes a true characteristic of myoglobin, making 'All of these' the correct choice.

Q63. Which of the following causes an increase in sodium reabsorption in the distal convoluted tubule?

• A. Increase in Aldosterone levels✓
• B. Increase in Antidiuretic Hormone (ADH) levels
• C. Decrease in aldosterone levels
• D. Decrease in Antidiuretic Hormone (ADH) levels

Explanation: Aldosterone, a hormone produced by the adrenal cortex, plays a crucial role in regulating sodium and potassium balance in the body. It enhances sodium reabsorption in the distal convoluted tubule and collecting duct of the nephron by increasing the number of sodium channels and sodium-potassium pumps. This process helps retain sodium in the body, contributing to increased blood pressure and reduced urine volume. In contrast, antidiuretic hormone (ADH) primarily focuses on water reabsorption, and changes in its levels do not directly affect sodium reabsorption. Therefore, the correct answer is an increase in aldosterone levels, which specifically targets sodium reabsorption.

Q64. Which one of the following characteristics is common both in humans and adult frogs?

• A. Four chambered heart
• B. Internal fertilization
• C. Nucleated RBCs
• D. Ureotelic mode of excretion✓

Explanation: Excretion of urea is known as ureotelism and the animals which excrete urea are called ureotelic. Ureotelic animals include Ascaris, earthworm (both are ammonotelic and ureotelic), cartilaginous fishes like sharks and sting rays, semiaquatic amphibians such as frogs and toads, aquatic or semiaquatic reptiles like turtles, terrapins and alligators, and man and all other mammals. Urea is less toxic and less soluble in water than ammonia. Hence, it can stay for some time in the body. Amphibian tadpole (e.g., tadpole of frog) excrete ammonia but after metamorphosis frog excretes urea.

Q65. Uric acid is the chief nitrogenous component of the excretory products of:

• A. Earthworm
• B. Cockroach✓
• C. Frog
• D. Man

Explanation: Cockroach shows uricotelism. Excretion of uric acid is known as uricotelism and the animals which excrete uric acid are called uricotelic. Animals which live in dry conditions have to conserve water in their bodies.Therefore, they synthesize crystals of uric acid from ammonia.Uric acid crystals are nontoxic and almost insoluble in water. Hence, these can be retained in the body for a considerable time. Uricotelic animals include most insects,(e.g., cockroach), land reptiles (e.g. lizards and snakes) and birds.

Q66. In sufficient or excess supply of water, reabsorption of water from filtrate is:

• A. Increased
• B. Maintained
• C. Reduced✓
• D. Stopped

Explanation: When sufficient or excess supply of water is available to our body, reabsorption from the glomerular filtrate will be reduced, and more and more water will be allowed to leave the body in the form of urine.

Q67. In restricted supply of water, concentration of the filtrate is increased by the following except :

• A. Counter Current
• B. Hormonal Mechanism
• C. Antidiuretic Hormone
• D. Aldosterone✓

Explanation: Aldosterone is associated with active reabsorption of salts not of water. Whereas, rest of the choices are associated with concentration of urine and conservation of water.

Q68. Conservation of water is the principal function of the body in:

• A. Surplus Supply of Water
• B. Restricted Supply of Water✓
• C. Sufficient Supply of Water
• D. Excess Supply of Water

Explanation: When the supply of water to the body is restricted, the water inside the body is conserved to compensate it and vice versa. Thus, the volume of the urine is reduced, and it becomes concentrated.

Q69. The deficiency of which of the following causes severe combined immunodeficiency?

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

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

Q70. Genes of interest can be selected from a genomic library by using:

• A. Cloning vectors
• B. DNA probes✓
• C. Gene targets
• D. Restriction enzymes

Explanation: A gene bank or genomic library is a complete collection of cloned DNA fragments that comprises the entire genome of an organism. Molecular probes are small DNA segments that are used to detect the presence of complementary sequences in nucleic acid samples in the genomic library. These are usually formed of 200­500 nucleotide sequences. These segments or probes are labeled either with radioactive or nonradioactive compounds. Probes with DNA sequences complementary to the gene to be isolated are used. They bind with the desired gene, making it visible and help in isolating it from the library.

Q71. Nucleotides sequence that is identical to its complementary strand when each is read in the same chemical direction for example i-e; 5'GATC3' 3'CATG5' these are called as:

• A. Flanking sequences
• B. Nucleotide order
• C. Palindromic sequences✓
• D. Antagonistic sequences

Explanation: Palindromic sequences occur when a sequence of base pairs reads the same in both directions on complementary strands, like 5' GATC 3' and 3' CTAG 5'. Such sequences play a crucial role in genetic engineering, particularly in restriction enzyme recognition and cutting of DNA. The other options do not fit this definition: Flanking sequences are adjacent to DNA regions of interest, Nucleotide order refers to the sequence without implying symmetry, and Antagonistic sequences is not a concept in DNA sequence terminology.

Q72. A technique used for correcting defective genes responsible for disease development:

• A. Gene therapy✓
• B. Cloning
• C. Tissue culture
• D. Gene sequencing

Explanation: Gene therapy is a technique that uses a gene(s) to treat, prevent or cure a disease or medical disorder.

Q73. Microscopic vesicles that spontaneously form when lipoproteins are put into a solution, are called:

• A. Liposomes✓
• B. Lysosomes
• C. Nucleosomes
• D. Peroxisomes

Explanation: Liposomes are spherical vesicles of of phospholipid bilayer which are used as a vehicle for administration of nutrients and pharmaceutical drugs and for insertion of desired genes. into cells or tissues.

Q74. The maximum amount of electrolytes and water (70 – 80 %) from the glomerular filtrate is reabsorbed in which part of the nephron?

• A. Ascending limb of loop of Henle
• B. Distal convoluted tubule
• C. Proximal convoluted tubule✓
• D. Descending limb of loop of Henle

Explanation: During glomerular filtration in kidneys, ultrafiltration of blood occurs i.e: almost all the constituents of plasma except proteins pass onto the Bowman’s capsule.Then nearly 99% of the filtrate is reabsorbed by renal tubules.The proximal convoluted tubules show maximum reabsorption and nearly all the essential nutrients and 70-80% of electrolytes and water are reabsorbed by this segment.

Q75. For defense against a virus attack, the body produces:

• A. Antibodies
• B. Histamines
• C. Antigens
• D. Interferons✓

Explanation: The correct answer is Interferons. Interferons are proteins produced by host cells in response to viral infections. They play a crucial role in the immune response by inhibiting viral replication within host cells and activating immune cells. While antibodies are essential for neutralizing viruses outside cells, they are not the primary defense against viruses that have already entered cells. Histamines are related to allergic responses, and antigens are not produced by the body but are targets for the immune system.

Q76. Phragmoplast is formed during:

• A. Metaphase
• B. Anaphase
• C. Telophase
• D. Cytokinesis✓

Explanation: Phragmoplast is a plant cell structure that plays a crucial role during cytokinesis. It consists of microtubules, actin filaments, and other molecules that facilitate the formation of the cell plate, which becomes the new cell wall separating the daughter cells. This structure is not involved in earlier phases of mitosis such as metaphase or anaphase, where the focus is on chromosome alignment and separation. It begins to form during telophase but is primarily associated with cytokinesis.

Q77. In the pancreas, lipase production is regulated by:

• A. Gastrin
• B. Secretin✓
• C. Insulin
• D. Lipids

Explanation: Secretin is the correct answer as it is a hormone produced by the intestinal mucosa in response to acidity in the duodenum, promoting the secretion of bicarbonate from the pancreas. This helps to neutralize stomach acid and create an optimal pH for pancreatic enzymes, including lipase, to function effectively. Gastrin primarily affects gastric acid secretion, insulin is responsible for glucose regulation, and lipids are substrates for digestion, not regulators of enzyme production.

Q78. A psychological condition usually seen in girls and young women, with loss of appetite, is:

• A. Obesity
• B. Malnutrition
• C. Anorexia Nervosa✓
• D. Dyspepsia
• E. Peptic ulcer

Explanation: Anorexia nervosa is a psychological disorder primarily affecting girls and young women, characterized by an intense fear of gaining weight and a distorted body image, leading to severe food intake restriction and loss of appetite. Unlike the other conditions listed, anorexia is specifically psychological and affects the demographic in question. Obesity is more about excessive weight gain, malnutrition is a broad term for nutrient deficiencies, dyspepsia is a digestive issue, and peptic ulcers are physical conditions of the digestive system.

Q79. Both T and B cells get maturation by the involvement of gene called:

• A. Phenyl alanine hydroxylase
• B. ADA✓
• C. Homogentisic acid dehydrogenase
• D. Phospho hexokinase

Explanation: ADA (adenosine deaminase) is involved in the maturation of T and B cells and therefore, the person lacking it are subjected to life threatening infection.

Q80. Although each cell contains a copy of all the genes of that genome, certain genes are:

• A. Amplified in mature specialized cells
• B. Turned off in mature specialized cells✓
• C. Lost in mature specialized cells
• D. Mutated in mature specialized cells

Explanation: When a cell is assigned a specialized job, only those genes remain active which are associated with that particular job, rest are turned off, however, they can be switched on again if needed.

Q81. The primary oocyte in mammals has which of the following structures around it?

• A. Zona Pellucida✓
• B. Zona Vasculosa
• C. Zona radiata
• D. None of them

Explanation: Among the given options, the correct structure that surrounds the primary oocyte in mammals is the Zona Pellucida.Zona Pellucida: The Zona Pellucida is a thick glycoprotein-rich layer that surrounds the mammalian oocyte. It is formed by the secretions of the oocyte itself and the surrounding follicle cells. The Zona Pellucida plays a crucial role in fertilization by mediating the interaction between sperm and oocyte and preventing polyspermy (fertilization by more than one sperm).Zona Vasculosa: The term "Zona Vasculosa" typically refers to the vascular zone found in the embryonic chick blastoderm, which is different from the structures surrounding the primary oocyte in mammals. It is responsible for supplying nutrients and oxygen to the developing embryo.Zona Radiata: The term "Zona Radiata" is often used to describe the outermost layer of the mammalian ovarian follicle. It consists of several layers of follicular cells that surround the Zona Pellucida. The Zona Radiata provides structural support and aids in the maturation and release of the oocyte during ovulation.In summary, the correct structure that surrounds the primary oocyte in mammals is the Zona Pellucida. The Zona Vasculosa refers to a vascular zone in the embryonic chick blastoderm, and the Zona Radiata describes the outermost layer of the ovarian follicle in mammals.

Q82. Among the following, which acid is an unsaturated acid:

• A. Butyric Acid
• B. Oleic Acid✓
• C. Palmitic Acid
• D. Both Oleic Acid and Palmitic Acid

Explanation: •A saturated fatty acid is one that lacks double bonds. Animal fat is commonly composed of saturated fatty acids. They are solid at room temperature.•Unsaturated fatty acid is one that has one or more double bonds in them. They are commonly found in plants and exist in liquid form at room temperature. Oleic acid has a double bond between C9 and C10, making it unsaturated.

Q83. Backbone of amino acids comprises of

• A. R group
• B. Amino group
• C. Carboxylic group
• D. Amino group, carboxylic group, hydrogen atom and R group.✓
• E. None of these

Explanation: Amino acids are molecules that combine to form proteins.Each amino acid contains an amino group,a carboxylic group,an r group and a hydrogen atom which is attached to the central alpha carbon.All of them form the basic skeleton of amino acids.

Q84. What is the subunit of DNA:

• A. Phosphoric Acid
• B. Base
• C. Nucleotide✓
• D. Sugar

Explanation: A nucleotide is the basic building block of nucleic acids(DNA and RNA).•It is composed of pentose sugar,phosphate and a nitrogenous base.•The four nitrogenous bases in DNA are Adenine,Guanine,Cytosine and Thymine.Options A,B and D are incorrect because all of them are subunits of the nucleotide itself,not DNA.

Q85. The type of bonding in 𝛼-Helix;

• A. 1,2 Glycosidic Linkage
• B. Ionic Bond
• C. Disulfide Bond
• D. Hydrogen Bond✓

Explanation: The alpha helix is basically found in secondary protein structures.•It is stabilized by hydrogen bonds between the carbonyl oxygen of one amino acid to the amino group of the second amino acid.•Ionic bonds are formed when a positively charged ion forms a bond with a negatively charged ion,one atom transfers the electron to the other one.For Example:Bond between sodium and chlorine.•A disulphide bond is a covalent bond between 2 sulfur atoms (-S-S-).Example:Cysteine,one of the 20 amino acids contains this kind of linkage. •Hydrogen bond is formed when a hydrogen atom forms a bond with a highly electronegative atom (N,O,F).For Example:Bonding between H2O molecules,HF etc.•1,2-Glycosidic linkage is found in sucrose which is a carbohydrate,but alpha helix is included in proteins.

Q86. Enzymes have what effect on the end-product?

• A. They alter the product
• B. The nature of the product is completely changed
• C. No effect✓
• D. The end product is not obtained

Explanation: Enzymes are biocatalysts that speed up chemical reactions by lowering activation energy. Due to this, the products are formed at a faster rate. But enzymes only affect the rate of reaction without being used up, they can't alter the structure of the final product. Options A, B, and D are incorrect because enzymes function as catalysts only in biochemical reactions.

Q87. Which of the following is not part of the first line of defense?

• A. Sebum
• B. Perspiration
• C. Interferon✓
• D. Epidermis

Explanation: The first line of defense includes physical and chemical barriers like the skin (including the epidermis), sebum, and perspiration, which help prevent pathogens from entering the body. Sebum and perspiration are secretions that support these barriers. Interferon, however, is part of the second line of defense. It is a protein that aids in the immune response by inhibiting viral replication and activating immune cells. This distinction makes interferon not a component of the first line of defense.

Q88. What are the functions of the inter, motor and sensory neurons in a reflex response?

• A. Option A✓
• B. Option B
• C. Option C
• D. Option D

Explanation: To relay nerve impulses from within the CNS, interneurons are used. To conduct the nerve impulses from the CNS to the effector, motor neurons are used. To conduct the nerve impulses from the receptors to the CNS, sensory neurons are used.

Q89. Blood group A negative can be donated to:

• A. O negative
• B. O positive
• C. A positive✓
• D. B positive

Explanation: If you have A negative blood you can donate to anyone with a blood type of A or AB regardless of the positive or negative. So only option C is consistent with this statement.

Q90. The region where the impulse moves from one neuron to another is called _.

• A. Axon
• B. Dendrites
• C. Synapse✓
• D. Thalamus
• E. Cerebellum

Explanation: Synapse, also called a neuronal junction, is the site of transmission of electric nerve impulses between two nerve cells (neurons) or between a neuron and a gland or muscle cell (effector).

Q91. Ascorbic acid (vitamin C) contains 40.92% carbon, 4.58% hydrogen and 54.5% of oxygen by mass. What is the empirical formula of ascorbic acid?

• A. C3H4O3✓
• B. C3H4O6
• C. CH4O3
• D. C6H4O3
• E. C2H5O3

Explanation: The empirical formula is the ratio between the number of atoms of different elements which is present in the molecule of the given compound. Empirical formulas usually give the proportion of the elements present in the molecule of the given compound but not the actual number of the atoms or how the atoms are arranged. Complete step by step answer: If the mass of the compound is given then the empirical formula is calculated by changing the mass of every element to moles and then by dividing every mole value by the lowest value of mole computed and then the value of mole is rounded off to the closest whole number. Given in the question: 100% of vitamin C contains 40.92% carbon by mass, 4.58% hydrogen, and 54.50% oxygen Or we can say that 100 g of vitamin C contains 40.92 g carbon by mass, 4.58 g hydrogen, and 54.50 g oxygen. The atomic mass of carbon = 12 g/mol The atomic mass of hydrogen = 1 g/mol The atomic mass of oxygen = 16 g/mol The number of moles is calculated by the ratio of the given mass to the molar mass. Number of moles of carbon = 40.92\12 = 3.4 mole Number of moles of hydrogen = 4.58\1 = 4.58 mole Number of moles of oxygen = 54.50\16= 3.40 mole The molar ratio of carbon, hydrogen, and oxygen is: C:H:O 3.4 : 4.58 : 3.4 = 3:4:3 C3H4O3 So, the correct answer is “Option A”. Note: If the molecular formula of a compound is given then to calculate the empirical formula from the molecular formula we have to divide all the subscripts in the empirical formula by the simplest whole number. The molecular formula is the actual whole number ratio of the elements present in the molecule of the compound.

Q92. 2 grams of H2 molecules contain _ molecules.

• A. 12.04 x 1023
• B. 6.02 x 1023✓
• C. 3.01 x 1023
• D. 1.008
• E. 2

Explanation: 1 mole of hydrogen contains = 2×1 = 2g2g of H2 contain = 2/2 × avogadro number = 1 × 6.022 × 10²³ = 6.022 × 10²³ molecules.

Q93. If we take 2.2g of CO2, 6.02 x 1021 atoms of nitrogen and 0.03g atoms of sulfur, then the molar ratio of CO2, N and S atoms will be:

• A. 1:2:5
• B. 5:1:2
• C. 2:5:3
• D. 5:1:3✓

Explanation: We have to calculate moles for each of the elements givenFor CO2 mass if given so use the formulamoles = mass/mr (Mr = 12 + 32 = 44)moles = 2.2/44 moles = 0.05Nitrogen atoms are given so using the formulaatoms = moles x avogadros constantmoles = atoms/ avogadros constant moles = 6.02 x1021 / 6.02x1023moles = 0.01For sulfur, gram atoms are given and gram atoms = molesSo, moles = 0.03Now calculating the molar ratioCO2 : N : S0.05 : 0.01 : 0.03 (Multiply by 100 to convert to whole numbers ratios already in lowest form)5 : 1 : 3 This is the following solution:

Q94. Equal weights of methane and hydrogen are mixed in an empty container at 25°C. The fraction of total pressure exerted by hydrogen is:

• A. ½
• B. 8/9✓
• C. 1/9
• D. 16/17

Explanation: According to Dalton's law of partial pressure, the total pressure of a mixture of gases is the sum of the partial pressure of the gases in the mixture. We can calculate the partial pressure by the following formula: Partial pressure H₂/ Partial pressure CH4 =Moles of H2/ Moles of CH4 pH2/ pCH4 = nH2/nCH4 We assume that x is the mass of hydrogen and methane each. The molecular mass of H2=2 The molecular mass of CH4=16 Mole = mass/Mr Moles of H2= x/2 Moles of CH4= x/16 Total moles= x/2 + x/16 = 9x/16 The partial pressure of H2= moles of H2/total moles =(x/2)÷(9x/16) =(x/2) x (16/9x) =8/9 so option B is the right answer.

Q95. Solid CO2 dry ice has a structure just like:

• A. Diamond
• B. NaCl
• C. Graphite
• D. None of the above✓

Explanation: Molecular crystals are substances that have relatively weak intermolecular binding, such as dry ice (solidified carbon dioxide), solid forms of noble gases (e.g., argon, krypton, and xenon), and crystals of numerous organic compounds.

Q96. Choose the correct statement:

• A. Ultraviolet radiation from sun causes a reaction that produces ozone✓
• B. Ozone hole is depletion in total amount of O
• C. A single chlorine free radical can destroy 10000 ozone molecules
• D. AII of above

Explanation: Ultraviolet radiations cause photochemical splitting of oxygen molecules in the stratosphere. The nascent oxygen combines with molecular oxygen to form ozone. In troposphere nascent oxygen comes from nitrogen dioxide. Option B is incorrect because ozone depletion does not reduce the amount of oxygen atoms, however it reduces the amount of ozone (O3) by converting it to oxygen gas O2.Option C is incorrect because a single chloride free radical can destroy upto 100,000 ozone molecules.

Q97. The enthalpy of certain reactions at 273 K is -20.75 kJ. The enthalpy of the same reaction at 373 K (if heat capacities of reactants and products are the same) will be:

• A. －20.75 kJ✓
• B. -2075 kJ
• C. Zero
• D. －20.75 x 373/273 kJ

Explanation: As it is provided in the given statement that heat capacities of reactants and products are the same, therefore there will be no energy change in the reaction. By Kirchoff's Rule; ∆Cp=∆H2-H1/T2-T1∆Cp(T2-T1)=∆H2-H1As, ∆Cp= 0 , ∆H2=H1 , therefore;H2= -20.75KJ

Q98. The compression factor (compressibility factor) for one mole of a Van der Waals gas at 00 C and 100 atmosphere pressure is found to be 0.5. Assuming that the volume of the gas molecule is negligible, calculate the Van der Waals constant 'a'.

• A. 1.254✓
• B. 2.87
• C. 3.76
• D. 1.34

Explanation: This is the following solution.

Q99. The relative abundance of isotopes of elements are measured by?

• A. Atomic Spectroscopy
• B. Ionic Spectroscopy
• C. Mass Spectroscopy
• D. Mass Spectrometry✓

Explanation: Atomic spectroscopy is a technique used to study the interaction of electromagnetic radiation with atoms.There is no such thing as "ionic spectroscopy" as a distinct technique or field of study. Mass spectroscopy isn't a termThe relative abundance of isotopes is measured by using mass spectrometry. Mass spectrometry is a technique used to determine the molecular weight and elemental composition of a sample by measuring the mass-to-charge ratio (m/z) of ions in the sample

Q100. Limiting reactant controls the amount of _ ?

• A. Reactant
• B. Products✓
• C. Both A & B
• D. None of these

Explanation: he limiting reactant controls the amount of products formed in a chemical reaction. The limiting reactant is the reactant that is completely consumed first, and it determines the maximum amount of product that can be formed. The other reactants, called excess reactants, are not completely consumed and are left over at the end of the reaction.So the answer is products.Here is an example. Let's say we have the following chemical reaction:2H2+ O2 → 2H2OThis reaction requires 2 moles of hydrogen gas for every 1 mole of oxygen gas. If we start with 1 mole of hydrogen gas and 2 moles of oxygen gas, then the hydrogen gas will be the limiting reactant. This is because the hydrogen gas will be completely consumed first, and only 1 mole of water will be formed. The oxygen gas will be left over in excess

Q101. A sample of 0.7 moles of metal 'M' reacts completely with an excess of fluorine to form 45 g of MF2. How many moles of F are present in it?

• A. 1.4 moles✓
• B. 2.4 moles
• C. 2 moles
• D. 1.2 moles

Explanation: 1 mole of metal formed one mole of MF2 molecule ∴ 0.7 mole of metal formed = 0.7 mole MF2 molecule ∵ Each molecule of MF2 contains = 2 F atoms ∴ 0.7 mole of MF2 molecule contains = 2 x 0.7 moles of F atom = 1.4 mole of F atom Hence, 45 g of MF2 molecule contains 1.4 moles 'F' atom.

Q102. The total number of neutrons in 5g of H2O are:1 NA = 6.023 x 1023

• A. 25 NA
• B. 1.1 NA
• C. 1.34 x 1024✓
• D. 0.5 NA

Explanation: To find the total number of neutrons in 5g of H2O, we start by calculating the number of moles of water:1. The molar mass of H2O is approximately 18 g/mol (2 for H and 16 for O).2. The number of moles in 5g of H2O is calculated as follows: Number of moles = mass (g) / molar mass (g/mol) = 5g / 18 g/mol ≈ 0.278 moles.3. Each molecule of H2O contains 2 hydrogen atoms (each with 0 neutrons) and 1 oxygen atom (with 8 neutrons), totaling 8 neutrons per molecule.4. The total number of molecules in 0.278 moles is: 0.278 moles x 6.023 x 1023 molecules/mole ≈ 1.67 x 1023 molecules.5. Therefore, the total number of neutrons in 5g of H2O is: 1.67 x 1023 molecules x 8 neutrons/molecule = 1.34 x 1024 neutrons, which corresponds to Option C. The other options are incorrect due to miscalculations or misunderstandings of stoichiometric principles.

Q103. If 9.8 g of sulfuric acid is dissolved in excess quantity of water, it will yield _ moles of hydrogen ion (H+) and _ moles of sulphate ions (SO42-).

• A. 0.1, 0.2
• B. 0.1, 0.3
• C. 0.2, 0.4
• D. 0.2, 0.1✓

Explanation: Mr (H2SO4) = 2(1) + 32 + 4 (16) = 98g.mol-1n(H2SO4)= 9.8/98= 0.1n(H+ ) = 2 x0.1 = 0.2n(SO4) = 0.1 x 1= 0.1

Q104. Which of the following is the electronic configuration of Potassium(K) Atomic number= 19K?

• A. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2
• B. 1s2, 2s2, 2p6, 3s2, 3p6, 3s2, 3d1
• C. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d5
• D. 1s2, 2s2, 2p6, 3s2, 3p6, 4s1✓
• E. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d10

Explanation: Option D is the correct option because this is the only option that has 19 electrons by adding manually.

Q105. The maximum number of electrons that an orbital can accommodate is/are:

• A. 0
• B. 1
• C. 2✓
• D. 3
• E. 4

Explanation: The maximum number of electrons in a single orbital is two. The maximum number of electrons an orbital can accommodate is 2. As in an orbital two electrons can never have the same values of all 4 quantum no.s according to Pauli’s exclusion principle. So to follow this rule, an orbital can accommodate 2 electrons only.

Q106. Which of the following statements is correct?

• A. Faraday's experiments proved the existence of electrons
• B. Crookes tube experiment demonstrated the presence of electrons in the atoms
• C. Radioactivity directly confirms the presence of electrons and protons
• D. Chadwick's experiment confirmed the presence of neutrons✓

Explanation: Option D is correct. James Chadwick's experiment involving the bombardment of beryllium with alpha particles led to the discovery of neutrons, neutral particles with a mass similar to that of protons. These particles do not have an electric charge, which distinguishes them from protons and electrons. The other options are incorrect because Faraday's work did not directly involve electrons, Crookes' experiment did not reveal protons, and radioactivity does not directly confirm the presence of electrons and protons.

Q107. A term in which no two electron can have the same set of four Quantum numbers is stated by

• A. Heisenberg's principle
• B. Pauli's exclusion principle✓
• C. Aufbau principle
• D. Hund's rule

Explanation: The heisenberg uncertainty principle states that certain pairs of physical properties, such as position and momentum, cannot be precisely determined simultaneously with arbitrary accuracy. Mathematically, the uncertainty principle is expressed as follows: (Δx . Δp ≥ h/4π) Hence, this is the incorrect answer. This is the correct answer because, The Pauli exclusion principle states that each electron in an atom must have a unique combination of quantum numbers. The four quantum numbers that describe an electron are: The principal quantum number (n) which determines the energy level or shell of the electron. The azimuthal quantum number (l) which specifies the subshell or orbital angular momentum of the electron. The magnetic quantum number (mₗ) which specifies orientation in space of a given orbital of particular energy and shape. The spin quantum number (mₛ) which specifies the spin state of an electron. The Aufbau principle, also known as the "building-up principle". According to the Aufbau principle, electrons occupy the lowest energy orbitals available first before moving to higher energy levels. The principle is based on the idea that electrons exist in discrete energy levels or shells surrounding the nucleus of an atom. Hence, this is the incorrect answer. Hund's rule states that when electrons are filling degenerate orbitals (orbitals with the same energy), they will occupy separate orbitals within the subshell before pairing up. In other words, electrons will try to maximize the number of unpaired electrons in a subshell or orbital before pairing begins. This principle is based on the concept of electron-electron repulsion. Hence, this is the incorrect answer.

Q108. The electronic configuration of iron is:

• A. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d5
• B. 1s2, 2s2, 2p6, 3s2, 3p6, 4s1, 3d5
• C. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d6✓
• D. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d3
• E. 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d2

Explanation: The electronic configuration of iron (Fe) with 26 electrons is: 1s2, 2s2, 2p6, 3s2, 3p6, 4s2, 3d6. This follows the Aufbau principle, where electrons fill orbitals starting from the lowest energy level. The 4s subshell is filled before the 3d subshell. Options A, B, D, and E account for fewer electrons than iron's 26, each missing one or more electrons in their configuration.

Q109. Which of the following gases is more ideal at STP?

• A. SO2
• B. NH3
• C. H2✓
• D. H2S

Explanation: In order to understand the answer to this question, we first need to address the definition of an ideal gas:Hydrogen is the closest to ideal gases because it has the least amount of excluded volume (thereby bringing its molar volume close to that of an ideal gas), and the weakest intermolecular attractions. (Refer to bullet points 1 and 2 above)Bear in mind that the smaller the atomic number, the weaker the London dispersion forces, and by extension the intermolecular interactions.H2 has the smallest molecular mass amongst the options given.

Q110. Which one is not related to evaporation?

• A. Continuous
• B. Endothermic
• C. Exothermic✓
• D. Spontaneous

Explanation: The molecules are absorbing heat, evaporation is called endothermic. Remember, endo means “to enter” while thermic means “heat.”So automatically, you choose the opposite of endothermic i.e. Exothermic.

Q111. How many balloons of capacity 0.25dm3 at 1atm pressure can be filled from a hydrogen gas cylinder of 5dm3 capacity at 10 atm?

• A. 50
• B. 90
• C. 180
• D. 200✓

Explanation: We will use Boyle's law for the relationship between volume and pressure. PV = k Where : P = Pressure V = Volume k = Constant Lets get PV for each : Balloon : 0.25 × 1 = 0.25...... k₁ Gas cylinder : 5 × 10 = 50......... k₂ To get the number n of the balloons the cylinder can supply we get : k₂ / k₁ = n 50 / 0.25 = 200 The answer is 200 balloons.

Q112. A crystal system having all sides (a, b and c) unequal and angles α = β = γ = 90 is:

• A. Cubic
• B. Rhombohedral
• C. Orthorhombic✓
• D. Hexagonal

Explanation: This is correct because an orthorhombic system has all three sides unequal (a ≠ b ≠ c), but all angles are 90° (α = β = γ = 90°).

Q113. Half atmospheric pressure is:

• A. 400 torr
• B. 50662 Pa✓
• C. 101.3 Pa
• D. 8.5 pounds

Explanation: Atmospheric pressure on sea level is 101,325 Pa/760 torr/14.7 pounds per inch. Half atmospheric pressure will be 50662 Pa/380 torr/7.35 pounds per inch. The closest to these values is option B, which is the correct option.

Q114. The value of S.T.P for 1 mole of any ideal gas is:

• A. 273.16 K and 1 atm✓
• B. 0oC & 1 mm Hg
• C. 273.16oC & 1 atm
• D. 0 K & 1 atm

Explanation: The standard temperature and pressure are 273.16K (0oC) and 1 atm. All the remaining options are incorrect.

Q115. The expression PV=nRT represents the:

• A. Dalton’s Law
• B. Avogadro’s Law
• C. General gas equation✓
• D. Van der Waals equation

Explanation: PV=nRT is a General gas equation for an ideal gas equation. Avagadro’s law is V1n2=V2n1, Dalton’s law is Ptotal=P1+P2+P3…, Van der Waal equation is (P+V2an2)(V−nb)=nRT.

Q116. The maximum possible number of electrons a shell 'n' can accommodate is given by:

• A. n
• B. n2
• C. 2n2✓
• D. n3
• E. 3n2

Explanation: The maximum number of electrons that can be in a shell is 2n2.

Q117. The radii of the second orbit of the hydrogen atom calculated from Bohr's model is:

• A. 0.529 Å
• B. 4.8 Å
• C. 2.116 Å✓
• D. 3.4 Å
• E. 1 Å

Explanation: In Bohr's model, the radius of the nth orbit of a hydrogen atom is given by the formula rn = 0.529 x n²/Z Å, where n is the principal quantum number and Z is the atomic number. For hydrogen, Z = 1. For the second orbit (n=2), the radius is calculated as:r2 = 0.529 x 2²/1 = 0.529 x 4 = 2.116 Å.Therefore, the correct answer is 2.116 Å. The other options are incorrect because they either represent the radius of a different orbit (e.g., 0.529 Å for n=1) or are arbitrary values that do not match the calculation for n=2.

Q118. The amount of energy released by absorbing an electron in the valence shell is:

• A. Ionization Energy
• B. Electron Affinity✓
• C. Electronegativity
• D. Atomic Radius
• E. Atomization Energy

Explanation: Electron Affinity is the correct answer because it is defined as the amount of energy released when an electron is added to a neutral atom to form an anion. This process is exothermic for most elements, meaning energy is released.Ionization Energy is incorrect because it involves removing an electron, not adding one, and thus requires energy. Electronegativity is a measure of an atom's ability to attract electrons in a bond and does not directly involve energy release upon electron addition. Atomic Radius is a measurement of size and has no direct correlation with energy release. Atomization Energy pertains to breaking molecules into atoms, not adding electrons to individual atoms.

Q119. For a multi-electron atom, the highest energy level among the following is

• A. n = 5, l = 0, m = 0 , s = +1/2
• B. n= 4 , l = 0 , m = 0 , s = - 1/2
• C. n= 3 , l = 1, m = 1 , s = - ½
• D. n= 5 , l = 1 , m = 0 , s = +1/2✓

Explanation: Higher the n + l value higher is the energy. If the n+ l value is same then higher energy corresponds to the greater n value orbital.

Q120. The thermal energy at constant pressure is called:

• A. Enthalpy✓
• B. Internal energy
• C. Heat capacity
• D. work done

Explanation: Enthalpy is defined as the sum of the internal energy of a system and the product of its pressure and volume. It is specifically used to describe the thermal energy of a system at constant pressure. Enthalpy change is related to the heat transfer occurring at constant pressure, making it the appropriate term for thermal energy under these conditions.

Q121. Born Haber cycle is used to determine:

• A. Electron affinity
• B. Lattice energy✓
• C. Crystal energy
• D. Both B and C

Explanation: The Born-Haber cycle is a thermochemical cycle that allows us to calculate the lattice energy of an ionic compound by considering the various energy changes involved in its formation. It uses Hess's Law to sum the enthalpy changes for individual steps, including ionization energy and electron affinity. Option A, 'Electron affinity,' while related to the cycle, does not represent the main purpose of the Born-Haber cycle, which focuses on lattice energy. Option C, 'Crystal energy,' is not a recognized term and does not apply, making it incorrect. Option D is also incorrect as it includes the invalid term 'crystal energy.' Thus, the correct and most relevant answer is Option B, 'Lattice energy,' as it directly corresponds to the primary purpose of the Born-Haber cycle.

Q122. CH3Cl + Cl2 ----> CH2Cl2 + HCl is an example of?

• A. Oxidation-Reduction (Redox) Reaction
• B. Addition Reaction
• C. Substitution Reaction✓
• D. Autoxidation Reaction
• E. Reduction Reaction

Explanation: The correct answer is a substitution reaction. In the reaction CH3Cl + Cl2 → CH2Cl2 + HCl, a chlorine atom substitutes a hydrogen atom in methyl chloride, resulting in methylene chloride and hydrogen chloride. This is characteristic of a substitution reaction. The other options are incorrect because the reaction does not involve electron transfer (redox), formation of a single product (addition), spontaneous oxidation with oxygen (autoxidation), or electron gain (reduction).

Q123. In the reaction 2Fe+Cl2 -> 2FeCl3

• A. Fe is reduced
• B. Fe is oxidized✓
• C. Cl2 oxidized
• D. None of the above

Explanation: The Oxidation state of iron(Fe) is changed from "0" to "+3". Hence it is oxidised.

Q124. The process in which electric current is used to carry out a non-spontaneous redox reaction is called:

• A. Electrolyte
• B. Electrolysis✓
• C. Metallic conductor
• D. None of the above

Explanation: Electrolysis is a process by which an electric current is passed through a substance to effect a chemical change. A chemical change is one in which the substance loses or gains an electron (oxidation or reduction).

Q125. If we move down the electrochemical series:

• A. Reduction potential will increase✓
• B. Reduction potential will decrease
• C. Oxidizing ability increase
• D. None of them

Explanation: Moving down the electrochemical series, the reduction potential will increase.The electrochemical series, also known as the activity series, is a list of elements or compounds arranged in order of their reduction potentials. Reduction potential is a measure of the tendency of a species to gain electrons and undergo reduction in a redox reaction.In the electrochemical series, elements or compounds higher up in the series have more negative reduction potentials, indicating a lower tendency to gain electrons and be reduced. Conversely, elements or compounds lower down in the series have more positive reduction potentials, indicating a greater tendency to gain electrons and be reduced.As you move down the electrochemical series, the reduction potential increase because the species are mire likely to accept electrons and be reduced. This is due to factors such as increasing atomic size, decreasing electronegativity, and decreasing ionization energy as you move down the series.In summary, as you move down the electrochemical series, the reduction potential increase, indicating an increasing tendency to undergo reduction.

Q126. The overall positive reduction potential value predicts that the process is:

• A. Not feasible
• B. Feasible✓
• C. Impossible
• D. No indication

Explanation: The more positive the potential, the greater the species' affinity for electrons, or the more the species tends to be reduced.

Q127. When fused PbBr2 is electrolyzed:

• A. Bromine appears at the cathode
• B. Lead is deposited at the cathode✓
• C. Lead appears at the anode
• D. None of the given options

Explanation: Fused lead bromide undergoes electrolysis which means splitting of ions using electrical energy and movement to ions to respective electrodes. During the electrolysis process, Pb2+ ions gain electrons at the cathode and become Pb atoms.

Q128. The breakdown of a substance with current is:

• A. Thermolysis
• B. Catalysis
• C. Electrolysis✓
• D. Photolysis

Explanation: 'Electrolysis' is the breakdown of a substance with the use of electricity. 'Thermolysis' is the breakdown of a substance using heat energy.'Photolysis' is the breakdown of a substance using light energy.'Catalysis' is, however, a misnomer; it is not the term used for the breakdown of a substance rather it implies the speeding up of the reaction rate.

Q129. The number of bond(s) between carbon and nitrogen atoms in a Nitrile is:

• A. One sigma and one pi
• B. Two sigma and one pi
• C. Only sigma
• D. One sigma and two pi✓

Explanation: Both the carbon and the nitrogen are sp hydridized which leaves them both with two p orbitals which overlap to form the two π bond in the triple bond. The bond angle in nitrile is 180° which give a nitrile functional group a linear shape.

Q130. Which of the following reaction has greater Kp than Kc?

• A. 2NO + Cl2 <--> 2NOCl
• B. 2SO2 + O2 <--> 2SO3
• C. 2NOCl <--> 2NO + Cl2✓
• D. N2 + 3H2 <--> 2NH3

Explanation: When the volume of products is greater than the volume of reactants, then Kp> Kc. From the options above, only Option C has more volume of gases at the product side as compared to the reactant side. We concluded this from the mole ratio of the equation which is 3 on the product side against 2 on the reactant side.

Q131. According to the law of mass action, "The rate of chemical reaction" is proportional to the:

• A. The Amount of product formed
• B. Product of the molar concentration of the reactant✓
• C. The initial concentration of reactant
• D. Catalyst

Explanation: The law of mass action states that reaction rate depends on how frequently reactant molecules collide. This frequency increases with their molar concentrations, so the rate is proportional to their product. Thus, option B correctly describes the law of mass action.

Q132. One Calorie is equal to:

• A. 4.18 kJ
• B. 4.18 J✓
• C. 0.418 KJ mol-1
• D. 0.418 KJ

Explanation: 1 calorie equals 4.18 J. It is very often confused with 1 kcal, which equals to 4.18 kJ

Q133. The equation N (g) + 3H (g) ⇋ 2NH (g) represents:

• A. Contact process
• B. Haber process✓
• C. Solvay’s process
• D. Haber process

Explanation: The reaction combines nitrogen and hydrogen to form ammonia (NH₃). This industrial method is specifically known as the Haber’s process. It is different from the Contact process (for H₂SO₄) and Solvay process (for Na₂CO₃).

Q134. The given diagram shows the enthalpy changes during a chemical reaction.

• A. An endothermic reaction
• B. An exothermic reaction✓
• C. An isothermic process
• D. A non-spontaneous process

Explanation: This diagram shows a reaction in which the reactants are at a greater energy level than the products, indicating that energy is released during the reaction, i.e. change in enthalpy or (H2-H1) would be negative, indicating that it is an exothermic reaction so, option B is correct.Option A describes an endothermic reaction which would have a diagram depicting products, at a higher energy level than the reactants.Option C indicates a process in which the heat energy of the system does not change, but the diagram itself shows a change in enthalpy.Option D cannot be determined from a mere energy diagram as shown.

Q135. Which of the following values of heat of formation indicates that the product is least stable?

• A. - 94 kcal
• B. + 21.4 kcal
• C. - 231 kcal
• D. + 64.8 kcal✓

Explanation: In the context of heat of formation (ΔH), a negative value indicates that the formation of the compound is exothermic, meaning the compound is more stable compared to its constituent elements in their standard states.So, the least stable compound among the options provided would have the most positive (ΔH) value and option d has the most positive value ,hence that is the correct option.

Q136. A body starts sliding on a rough horizontal surface with a speed of 10 m/s. If the coefficient of friction is 0.2, find the distance traveled by the body before coming to rest. (g = 10m/s)

• A. 15 m
• B. 25 m✓
• C. 35 m
• D. 40 m
• E. 55 m

Explanation: Given that: v = 10 and u = 0.2 and g = 10 Solution = Using F = μN then, = μmg (here N = mg) So from above (ma = μmg); we got a = μg Now a = 0.2×10 = 2 m/s2Now using equation of motion V2=u2+2as 0 = 10×10 +2×2×s In solving it, we got s = 100/4 = 25 m Hence we get the correct answer.

Q137. Assume that you have two balls of Identical volume, one weighing 2 Newtons and the other 10 Newtons. Both are falling freely after being released from the same point simultaneously. Which of the following will then be true: I. The 10 N ball falling freely from rest will be accelerated at a greater rate than the 2 N ball II. At the end of the 4s of freefall, the 10 N ball will have 5 times the momentum of the 2 N ball III. At the end of the 4s of free fall, the 10 N ball will have the same kinetic energy as the 2 N ball IV. The 10 N ball possesses greater inertia than the 2 N ball

• A. I, Il and Ill only
• B. I and II only
• C. II and IV only✓
• D. IV only
• E. None of these

Explanation: Acceleration of free fall acts equally on all masses, this is why both objects despite having different masses have the same speed at any point in time. Statement II is correct because two objects have the same velocity but one having 5 times more mass than the other will have 5 times more momentum than the other object. Statement IV is also correct because inertia depends upon mass since a 10N ball has a higher mass it will have greater inertia. Statement III is wrong because objects have different masses so their kinetic energy can not be the same. Statement I is wrong because objects accelerate irrespective of their masses as mentioned before.

Q138. At the instant the traffic light turns green, an automobile starts with a constant acceleration of 2.1 m/s2. At the same instant a truck, traveling with a constant speed of 9.2 m/s, overtakes and passes the automobile. How far beyond the traffic signal will the automobile overtake the truck?

• A. 40 m
• B. 30 m
• C. 90 m
• D. 120 m
• E. 80.6 m✓

Explanation: The correct option is 80.6 m i.e. option E. Following is the explanation.

Q139. A ball of mass m moving with a horizontal velocity v strikes the bob of a pendulum at rest. The mass of the bob of the pendulum is also m. During this collision, the ball sticks with the bob of the pendulum. The height to which the combined mass rises:

• A. v2/g
• B. v2/2g
• C. v2/4g
• D. v2/8g✓
• E. v2/7g

Explanation: The explanation is given below;

Q140. A car covers the first half of a certain distance with a speed V1 and the second half, with a speed V2. Find the average speed during the whole journey?

• A. Option A
• B. Option B✓
• C. Option C
• D. Option D
• E. Option E

Explanation: Average speed= total distance/total timeThe car’s journey can be divided into two equal parts of distance ‘d’. Since both distances are equal,Total distance= 2dTotal time= d/v1 (for first part) and d/v2 (for second part)Average speed= 2d / d(1/v1+1/v2)d cancels out leaving 2 / (v1+v2/v1v2)Which can be written as 2v1v2 / v1+v2That is consistent with option B.

Q141. If the volume of a gas is fixed then on increasing its temperature, its pressure_

• A. Gets negligible
• B. Gets constant
• C. Rises✓
• D. Falls

Explanation: Gay-Lussac's Law. This law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature. With an increase in temperature, the pressure will go up.If the volume of a gas is fixed (constant volume), the relationship between pressure P, temperature T and the other gas properties is described by the ideal gas law:PV=nRTFrom this equation, we can derive that, for a fixed volume:P∝TThis means that pressure is directly proportional to temperature when volume is constant. Therefore, if the temperature is increased, the pressure also increase.

Q142. A copper wire has resistances 10 ohms and 20 ohms at temperature 0 C and 10 C respectively. What is the temperature coefficient of the copper wire?

• A. 0.1 K-1✓
• B. 0.02 K-1
• C. 0.01 K-1
• D. 0.2 K-1

Explanation: You can solve the question using following solution:

Q143. Which of the following is not a base unit in the SI system?

• A. Ampere
• B. Second
• C. Meter per second✓
• D. Candela

Explanation: In summary, the correct answer is option c) Meter per second, as it is not a base unit in the SI system. The other options (a, b, and d) represent base units: ampere for electric current, second for time, and candela for luminous intensity.

Q144. The force which will accelerate a 25 kg mass at 98 cm/s2 on a smooth horizontal plane is:

• A. 200 Newton
• B. 1950 Newton
• C. 19.6 Newton
• D. 24.5 Newton✓
• E. 1960 Newton

Explanation: F=maF=(25 kg)(98/100 m/s2)F=24.5 N

Q145. At the highest point of the trajectory, which of the following quantities is zero?

• A. Horizontal velocity
• B. Total velocity
• C. Vertical velocity✓
• D. None of these options are correct

Explanation: The vertical velocity component of a projectile is 0 at a maximum height due to the action of acceleration due to gravity which acts in the direction opposite to that of the velocity and reduces its values constantly.Hence, C is the correct option

Q146. When photons are incident on a metal, electrons are emitted. The process is called:

• A. Photoelectric effect✓
• B. Pair production
• C. X-ray production
• D. Gamma ray production
• E. Radioactive capture

Explanation: Photoelectric effect, a phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation. The effect is often defined as the ejection of electrons from a metal plate when light falls on it.

Q147. At every point of the trajectory of projectile, which of the following quantities is always zero?

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

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

Q148. Which of the given motion is a type of 2D motion?

• A. Circular
• B. Pendulum motion
• C. Projectile motion
• D. All of these✓

Explanation: Correct option is D. All these are examples of 2D motion. Two-dimensional (2D) motion means motion that takes place in two different directions or axis (or coordinates) at the same time.

Q149. A projectile is launched with vertical kinetic energy, K, at an angle of 8. Its variation with kinetic energy is?

• A. Parabolic✓
• B. Periodic
• C. Hyperbolic trajectory
• D. Linear

Explanation: Projectile motion is parabolic because the vertical position of the object is influenced only by a constant acceleration and also because horizontal velocity is generally constant. Put simply, basic projectile motion is parabolic because of its related equation of motion.

Q150. The projectile motion of an object on Earth is always _.

• A. Linear
• B. Parabolic✓
• C. Cubic
• D. Inverse

Explanation: A projectile’s motion is parabolic because it is affected by gravity. Gravity causes the projectile to fall in a curved path, rather than a straight line. The equation for projectile motion takes into account the force of gravity, which is why the path of a projectile is always a parabola.

Q151. When a source is moving towards a stationary observer, the apparent change in frequency will be:

• A. Greater than the original frequency✓
• B. Remains the same as that of original frequency
• C. Smaller than the original frequency
• D. None of the above

Explanation: Option A: The apparent change in frequency will be greater than the original frequency when a source is moving towards a stationary observer. This is because the waves from the source are compressed as they approach the observer, which increases the frequency of the waves.The opposite is true when the source is moving away from the observer. In that case, the waves are stretched out, which decreases the frequency of the waves.This is known as the Doppler effect. It is a phenomenon that occurs when there is a relative motion between a source of waves and an observer. The Doppler effect can be observed with sound waves, light waves, and other waves. Option B: This is not possible. The frequency of the waves from the source will always change when there is a relative motion between the source and the observer. The only way that the frequency of the waves would remain the same is if the source and the observer were moving at the same speed in the same direction. Optio C: This is possible. When a source is moving away from a stationary observer, the waves from the source are stretched out as they move away from the observer, which decreases the frequency of the waves. This is known as the redshift. The redshift is a phenomenon that occurs when there is a relative motion between a source of waves and an observer, and the source is moving away from the observer. The redshift can be observed with light waves, and it is used to measure the expansion of the universe. Option D: This is not possible. The frequency of the waves from the source will always change when there is a relative motion between the source and the observer. The only way that the frequency of the waves would not change is if the source and the observer were not moving relative to each other.

Q152. If the waves interfere constructively, the amplitude of the resulting wave would be:

• A. Less than either of the individual waves
• B. Greater than either of the individual waves✓
• C. Equal to the shortest of the individual waves
• D. Equal to the greatest of the individual waves

Explanation: Option A: The amplitude of the resulting wave can never be less than either of the individual waves. This is because the crests of the two waves cannot cancel each other out completely. Even if the two waves are out of phase by 180 degrees, the troughs of the two waves will still add together to form a wave with some amplitude. Option B: The amplitude of the resulting wave would be greater than either of the individual waves. When two waves interfere constructively, the crests of the two waves line up, resulting in a wave with an amplitude that is equal to the sum of the amplitudes of the two individual waves. For example, if two waves with amplitudes of 1 cm and 2 cm interfere constructively, the amplitude of the resulting wave will be 3 cm. Option C: The amplitude of the resulting wave can also never be equal to the shortest of the individual waves. This is because the crests of the two waves cannot be perfectly aligned if the waves have different amplitudes. Option D: The amplitude of the resulting wave can be equal to the greatest of the individual waves. This happens when the two waves have the same amplitude and are in phase.

Q153. If a compressible medium has bulk modulus denoted by B and density denoted by P, then a Newton's formula for the speed of sound in a medium is _.

• A. V = √(B / P)✓
• B. V = √(B * P)
• C. V = B / P
• D. V = √(P / B)

Explanation: The speed of sound in a compressible medium is given by Newton's formula: V = √(B / P), where B is the bulk modulus and P is the density of the medium. The formula shows that the speed of sound is directly proportional to the square root of the ratio of the bulk modulus to the density. This is because a higher bulk modulus (indicating a stiffer medium) and a lower density both contribute to a higher speed of sound.Option A is correct because it correctly reflects this relationship. Option B is incorrect as it suggests multiplying the bulk modulus by the density, which does not describe the speed of sound. Option C is incorrect because it lacks the square root, which is necessary for the correct calculation. Option D is incorrect as it reverses the roles of bulk modulus and density.

Q154. Laplace's correction to Newton’s formula is based on the fact that the compressions and rarefactions occur as _.

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

Explanation: Laplace's correction to Newton’s formula recognizes that sound waves involve rapid compressions and rarefactions where there is insufficient time for heat exchange with surroundings, making the process adiabatic. Newton's original assumption of an isothermal process (constant temperature) was incorrect because it fails to consider the rapid temperature changes accompanying pressure variations in sound waves.The adiabatic process assumption accounts for these temperature changes, leading to a more accurate formula for sound speed in gases. The other processes—isochoric (constant volume) and isobaric (constant pressure)—do not describe the conditions experienced during sound wave propagation.

Q155. The object oscillates due to:

• A. A restoring force✓
• B. Its weight
• C. Centripetal force
• D. Force of friction

Explanation: An object in such motion oscillates about an equilibrium position due to a restoring force or torque. Such force or torque tends to restore (return) the system toward its equilibrium position no matter in which direction the system is displaced.

Q156. If f1 and f2 are frequencies of two tuning forks, such that f1 < f2, then the number of beats produced in one second is:

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

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

Q157. A steel wire hangs vertically from a fixed point, supporting a weight of 80 N at its lower end. The diameter of the wire is 0.50 mm and its length from the fixed point to the weight is 1.5 m. If the density of steel wire = 7.8 x 103 kg/m3, then what is the fundamental frequency emitted from the wire?

• A. 76 Hz✓
• B. 176 Hz
• C. 50 Hz
• D. 150 Hz

Explanation: Tension acting on the wire is T = 80 N, length of wire from the fixed point to the weight is L = 1.5 m. We know, density of steel is ρ = 7800 kg/m³, so the linear mass density of steel wire, μ = ρ A = 7800 kg/m³ × π(0.50 × 10⁻³ m)²/4 m² = 1.53 × 10⁻³ kg/m.

Q158. A wire has a spring constant of 5 x 104 N m-1. It is stretched by a force to the extension of 1.4 mm. Calculate the strain energy stored in the wire.

• A. 4.9 x 10-5 J
• B. 4.9 x 10-2 J✓
• C. 4.9 J
• D. 4.9 x 10-3 J

Explanation: E=0.5kx^2E=0.5(50000)(0.0014)2 =0.049 J

Q159. When the length of a simple pendulum is doubled, the ratio of its new time period to old time period is:

• A. 3√2
• B. 1√2
• C. 2√2
• D. √2✓

Explanation: The formula for time period is: T = 2π x √L/gUsing this formula, we see that doubling length results in multiplying time period with √2.

Q160. In simple harmonic motion, acceleration will be maximum, when the object is at:

• A. Maximum displacement from the mean position✓
• B. Centre position
• C. Half of the maximum displacement from mean position
• D. Mean position

Explanation: When displacement is maximum, acceleration will be maximum. The displacement and acceleration are related by the equation, a= -w2x, where 'a' (acceleration) and 'x' (displacement) are proportional.

Q161. Simple Harmonic Motion of a body is described by which statements mentioned below:K: K.E is maximum when displacement x = 0L: P.E is maximum when x = 0M: P.E is maximum when x = ± x0

• A. K and L
• B. K and M✓
• C. K, L and M
• D. L and M

Explanation: Option B is the correct choice because it accurately describes the energy conditions in simple harmonic motion. Kinetic energy (K.E) reaches its maximum when the displacement is zero (x = 0), as the body is moving fastest through the equilibrium position. Potential energy (P.E), on the other hand, is maximum at the extreme positions (x = ± x0) because these are the points of maximum displacement from the equilibrium position. Option A is incorrect because it incorrectly states that potential energy is maximum at x = 0. Option C includes the same incorrect statement as Option A. Option D is incorrect for the same reason as it includes the incorrect statement that potential energy is maximum at x = 0.

Q162. If the time period of the oscillation is 20 micro-sec, then what will be the frequency of that oscillating body?

• A. 5000 Hz
• B. 50000 Hz✓
• C. 20000 Hz
• D. 1000 Hz

Explanation: T=1/FT=1/20×10-6F = 50000 Hz.

Q163. In SHM the kinetic energy of the body is maximum when:

• A. The body is at mean position✓
• B. The body is at extreme position from the mean
• C. The body is exactly half way down between mean and extreme position
• D. The body is somewhere between mean and extreme position

Explanation: In simple harmonic motion, there is a continuous interchange of kinetic energy and potential energy. At maximum displacement from the equilibrium point, potential energy is a maximum while kinetic energy is zero. At the equilibrium point (mean position) the potential energy is zero and the kinetic energy is a maximum.

Q164. A wave passes through a medium; each particle of the medium performs 100 complete vibrations in 5 seconds. What is the frequency of the wave?

• A. 2 Hz
• B. 20 Hz✓
• C. 4 Hz
• D. 40 Hz

Explanation: Vibrations = 100Time = 5 sFrequency = vibrations/time = 100/5 = 20 HzHence, option B is the correct option.

Q165. At the top of the trajectory of a projectile, the acceleration is:

• A. g✓
• B. 0
• C. 2g
• D. g/2

Explanation: At the top of the trajectory, the velocity of the projectile is zero but the acceleration is still directed downward and is equal to the acceleration due to gravity that is 9.8 m/s2.

Q166. A body of mass 5 kg, projected at an angle of 45° from the ground covers a horizontal range of 45 m. The acceleration due to gravity is g = 10 m/s^2. What is the velocity with which it was projected?

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

Explanation: Explanation is given below.

Q167. A plane is moving with speed v at a height 'h' in the horizontal direction. The time taken to reach the ground is:

• A. √2g/u
• B. None of these
• C. √(2h/g)✓
• D. √(2u/g)

Explanation: If we solve the second equation of motion for time:h = ut + 1/2gt2Since it is moving with v velocity therefore the initial velocity u must have been zeroh = 1/2gt2t2 = 2h/gt = √2h/g

Q168. If a wave can be polarized, it means, it is:

• A. Longitudinal wave
• B. Stationary wave
• C. Superimposed wave
• D. Transverse wave✓

Explanation: Only transverse waves can be polarised. Longitudinal waves cannot be polarised.Transverse: vibrations perpendicular to the direction of travel of the wave.Longitudinal: vibrations parallel to the direction of travel of the wave.Sound waves are longitudinal so they cannot be polarised.Polarised: the wave vibrations occur in one plane onlyUnpolarised: the wave vibrations occur in all planes perpendicular to the direction of travel.The reason that only transverse waves can be polarised is that their vibrations can potentially occur in all directions perpendicular to the direction of travel. It is therefore possible to confine the vibrations to a single plane. Or put another way an unpolarised transverse wave is a 3D shape, it is therefore possible to confine it to a 2D shape (a plane). The vibrations of a longitudinal wave occur along a single line, it is therefore not possible to confine that to a plane, i.e. a 1D shape cannot be confined within a 2D shape. Similarly, Stationary waves and superimposed waves can not be polarised as they are along a single line.VIDEO EXPLANATION

Q169. What is true about the electric field and electric force?

• A. Electric field lines are towards negative and electron flow in same direction
• B. Electric field lines are towards positive and electron flow in opposite direction
• C. Electric field lines are towards the negative and electrons flow in the opposite direction.✓
• D. Electric field lines are positive and electrons flow in the same direction.

Explanation: Electric field lines always point away from a positive charge and towards a negative point. In fact, electric fields originate at a positive charge and terminate at a negative charge.This shows that OPTION B and D ARE INCORRECT. Electrons flow from lower potential terminal to higher potential terminal being negatively charged particles it flows from negative to positive poles hence it is the opposite direction as the electric field.So,OPTION C is incorrect.

Q170. If the amplitude is 200, the intensity is 300 When the amplitude is increased to 800 then what will be the intensity?

• A. 1200
• B. 1400
• C. 1600
• D. 1800
• E. 4800✓

Explanation: We know that The intensity of a wave is directly proportional to the square of its amplitude Mathematically-> I x a2HereI = intensitya = amplitudeAccording to the question, we are asked to find the new intensity given that If the amplitude is 200, the intensity is 300. When the amplitude is increased to 800HenceI = 300a = 200a' = 800Increase in amplitude (A)-> A = a'/aHence-> A = 800/200On further simplificationWe get-> A = 4Increase in amplitude (squared)-> A2 = 42-> A2 = 16Amplitude squared increases by a factor of 16-> I' = I x A2HereI' = new intensityI = initial intensityA² = squared amplitude factorIf the amplitude is 200, the intensity is 300. When the amplitude is increased to 800.HenceI = 300 We found out thatA² = 16Substituting the values-> I' = 300 x 16On further simplification-> I' = 4800HenceNew intensity = 4800When the amplitude is increased to 800 then the intensity will be 4800.

Q171. If the speed of waves is 10m/sec and its frequency is 5Hz, find its wavelength:

• A. 1
• B. 2✓
• C. 4
• D. 6

Explanation: V=F λ λ = v/f λ =10/5 λ = 2m

Q172. 12,32,72,152 _

• A. 312✓
• B. 325
• C. 515
• D. 613

Explanation: 12+20=3232+40=7272+80=152so 160 should be added in 152152+160=312

Q173. Find the missing number in the series: 4, 6, 10, 14, 22, 26, 34, 38, 46, ?

• A. 62
• B. 58✓
• C. 26
• D. 42

Explanation: This series is generated by multiplying 2 by the sequence of prime numbers. The terms are 2×2, 2×3, 2×5, 2×7, 2×11, and so on. The next prime after 23 is 29, so the missing term is 2 × 29 = 58.

Q174. In the following question, by using which mathematical operators will the expression become correct?18 ? 6 ? 9 ? 27

• A. x, ÷ and =
• B. ÷, x and =✓
• C. x, + and =
• D. +, - and =

Explanation: By inserting the operators '÷', '×', and '=', the expression becomes 18 ÷ 6 × 9 = 27. This simplifies to 3 × 9 = 27, which is a correct statement.

Q175. Find the missing number in the series3, 7, 16, 35, ?, 153

• A. 84
• B. 74✓
• C. 78
• D. 63

Explanation: The pattern is to multiply by 2 and then add a sequentially increasing number (×2+1, ×2+2, ×2+3, ...). So, 7 = 3×2+1; 16 = 7×2+2; 35 = 16×2+3. The missing term is 35×2+4 = 74.

Q176. Fact 1: A boy has four cars.Fact 2: Two of the cars are red.Fact 3: He has one sports car. If the above three statements are facts then which of the following statement will also be a fact? I. The boy has a red sports car.II. He has 2 corollas.III. His favorite color is red.

• A. Only statements I and II are correct
• B. Only statement II is correct
• C. Only statement III is correct
• D. None of the statements is a fact✓

Explanation: There is not enough information to support any of the statements. The boy has a sports car but it is not known which of his vehicles is red. The brands of the cars are not given hence there is no way to prove that two of his cars are corollas. There is no way to know if the boy's favorite color is red just because he has two red cars.

Q177. Statements:All apples are bananas.No banana is a mango.Some mangoes are oranges.Conclusions:(I) All oranges can never be bananas.(II)Some mangoes are apples.

• A. Only conclusion (I) follows✓
• B. Only conclusion (II) follows
• C. Both conclusions follow
• D. Both of them do not follow

Explanation: Conclusion I is correct since it is stated that some mangoes are oranges and no mango can be a banana thus oranges cannot be bananas.Conclusion II is incorrect since mangoes cannot be bananas and only bananas can be apples.Let's analyze the statements and conclusions:Statements:1. All apples are bananas. (This statement is false, as apples and bananas are different fruits.)2. No banana is a mango. (This statement is true, as bananas and mangoes are different fruits.)3. Some mangoes are oranges. (This statement is false, as mangoes and oranges are different fruits.)Conclusions:(I) All oranges can never be bananas.This conclusion is true, based on the statements. Since no banana is a mango (statement 2), and some mangoes are oranges (statement 3), we can infer that oranges and bananas are distinct and do not overlap.(II) Some mangoes are apples.This conclusion is false, based on the statements. Statement 1 says all apples are bananas, but it does not imply that mangoes are apples. In fact, statement 2 explicitly states that no banana is a mango, suggesting that mangoes and apples are not equivalent.So, conclusion (I) is true, and conclusion (II) is false.

Q178. Sick is to Sack as Lick is to:

• A. Lack✓
• B. Luck
• C. Eat
• D. Meat
• E. Lock

Explanation: Rhyming words I was replaced by A

Q179. Statements: 1. Blueberries cost more than strawberries. 2. Blueberries cost less than raspberries. 3. Raspberries cost more than strawberries and blueberries. If the first two statements are true, the third statement is:

• A. True✓
• B. False
• C. Uncertain
• D. None of these

Explanation: From the first two statements, we can establish the cost order: Raspberries > Blueberries > Strawberries. This directly confirms that raspberries cost more than both of the other fruits, making the third statement true.

Q180. " I. There has been opposition by the protestors over the government's decision of removal of subsidy on fertilizers. II. The government has decided to remove subsidy on some of the items to bring a reform to the economy.

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

Explanation: The correct answer is that statement II is the cause and statement I is its effect. The government's decision to remove subsidies on some items to reform the economy (Statement II) caused protestors to oppose this decision (Statement I). Option A is incorrect because statement I is an effect, not an independent cause. Option B is incorrect because statement II is a cause, not an effect. Option D reverses the actual cause and effect sequence, making it incorrect as well.