Correct Answer: (b)
Hyperthyroidism leads to Graves' disease.
Q2. Stirred-tank bioreactors have been designed for
Correct Answer: (c)
The stirrer ensures uniform mixing and aeration.
Q3. A few drops of sap were collected by cutting across a plant stem by a suitable method. The sap was tested chemically. Which one of the following test results indicates that it is phloem sap ?
Correct Answer: (b)
Phloem sap is alkaline (pH 7.5 - 8.5) and contains sucrose.
Q4. Genetic drift operates in
Correct Answer: (a)
Drift is significant in small, isolated populations.
Q5. Interspecific hybridization is the mating of
Correct Answer: (b)
Hybridization between different species (e.g., mule).
Q6. You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?
Correct Answer: (b)
The balance of Auxin (roots) and Cytokinin (shoots) is essential for morphogenesis.
Q7. Which of the following is correct regarding AIDS causative agent HIV?
Correct Answer: (b)
HIV has 2 identical RNA strands and 2 Reverse Transcriptase enzymes.
Q8. Which is essential for the growth of root tip?
Correct Answer: (c)
Calcium is required for cell division and the formation of the cell plate.
Q9. Red List contains data or information on
Correct Answer: (c)
The IUCN Red List tracks the status of threatened and endangered species.
Q10. The mechanism that causes a gene to move from one linkage group to another is called
Correct Answer: (c)
Translocation is the movement of a gene segment to a non-homologous chromosome.
Q11. The partial pressure of oxygen in the alveoli of the lungs is
Correct Answer: (b)
Alveolar pO2 (~104) is higher than blood pO2 (~40).
Q12. Conifers are adapted to tolerate extreme environmental conditions because of
Correct Answer: (c)
Thick cuticles and sunken stomata are key xerophytic adaptations in conifers.
Q13. Methanogens belong to
Correct Answer: (b)
Methanogens are specialized Archaebacteria found in anaerobic habitats.
Q14. Serum differs from blood in
Correct Answer: (c)
Serum = Plasma minus Clotting factors.
Q15. The balloon-shaped structures called tyloses
Correct Answer: (c)
Tyloses are ingrowths of xylem parenchyma into vessel lumens, often blocking them.
Q16. Match the stages of meiosis in Column-I to their characteristic features in Column-II and select the correct option using the codes given below :
Q34. Name the blood cells, whose reduction in number can cause clotting disorder, leading to excessive loss of blood from the body.
Correct Answer: (d)
Thrombocytes (Platelets) are required for blood clotting.
Q35. Which one of the following statements is not correct?
Correct Answer: (c)
Plantlets in potato and ginger arise from the 'nodes', not the internodes.
Q36. Taylor conducted the experiments to prove semiconservative mode of chromosome replication on
Correct Answer: (b)
Taylor used radioactive thymidine on Vicia faba (Faba bean) roots.
Q37. Smooth muscles are
Correct Answer: (a)
Smooth muscles are non-striated, involuntary, and spindle-shaped.
Q38. If '+' sign is assigned to beneficial interaction, '-' sign to detrimental and '0' sign to neutral interaction, then the population interaction represented by '+' '-' refers to
Correct Answer: (d)
Parasitism involves one winner (+) and one loser (-).
Q39. The primary producers of the deep-sea hydrothermal vent ecosystem are
Correct Answer: (b)
Without light, chemosynthetic bacteria use chemical energy to produce organic matter.
Q40. Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because
Correct Answer: (b)
The negative intrapleural pressure prevents collapse.
Q41. Which of the following is the correct sequence of events in 'the origin of life' ? I. Formation of protobionts II. Synthesis of organic monomers III. Synthesis of organic polymers IV. Formation of DNA-based genetic systems
Correct Answer: (c)
Standard chemical evolution sequence.
Q42. A non-proteinaceous enzyme is
Correct Answer: (b)
Ribozymes are catalytic RNA molecules.
Q43. Which of the following is the least likely to be involved in stabilizing the three-dimensional folding of most proteins?
Correct Answer: (d)
Ester bonds are not typically involved in protein folding.
Q44. If a colour-blind man marries a woman who is homozygous for normal colour vision, the probability of their son being colour-blind is
Correct Answer: (a)
Sons inherit the normal X from the mother.
Q45. Match Column-I with Column-II and select the correct option using the codes given below :
Q57. In male cockroaches, sperms are stored in which part of the reproductive system?
Correct Answer: (a)
Sperms are stored in seminal vesicles for maturation.
Q58. Choose the correct statement.
Correct Answer: (b)
Cyclostomes lack jaws and paired fins (Agnatha).
Q59. Phytochrome is a
Correct Answer: (d)
Phytochrome is a pigment-bearing protein (chromoprotein).
Q60. Embryo with more than 16 blastomeres formed due to in vitro fertilization is transferred into
Correct Answer: (a)
IUT transfers embryos with > 8 cells to the uterus.
Q61. Osteoporosis, an age-related disease of skeletal system, may occur due to
Correct Answer: (c)
Post-menopausal estrogen deficiency leads to bone loss.
Q62. Biochemical Oxygen Demand (BOD) may not be a good index for pollution for water bodies receiving effluents from
Correct Answer: (c)
Petroleum effluents contain non-biodegradable chemicals that BOD doesn't capture.
Q63. When cell has stalled DNA replication fork, which checkpoint should be predominantly activated?
Correct Answer: (b)
The G2/M checkpoint ensures DNA is correctly replicated before mitosis.
Q64. The part of nephron involved in active reabsorption of sodium is
Correct Answer: (b)
70-80% of electrolytes are reabsorbed in the PCT.
Q65. Which of the following biomolecules is common to respiration-mediated breakdown of fats, carbohydrates and proteins?
Correct Answer: (d)
Acetyl CoA is the common intermediate where various metabolic pathways converge into the Krebs cycle.
Q66. How many plants among Indigofera, Sesbania, Salvia, Allium, Aloe, mustard, groundnut, radish, gram and turnip have stamens with different lengths in their flowers?
Correct Answer: (b)
Mustard, Radish, Turnip (tetradynamous) and Salvia have stamens of different lengths.
Q67. Match Column-I with Column-II for housefly classification and select the correct option using the codes given below :
a. Family
(i) Diptera
b. Order
(ii) Arthropoda
c. Class
(iii) Muscidae
d. Phylum
(iv) Insecta
Correct Answer: (a)
Musca domestica: Family Muscidae, Order Diptera, Class Insecta, Phylum Arthropoda.
Q68. A true breeding plant is
Correct Answer: (c)
True breeding implies homozygosity and stable inheritance of traits.
Q69. Free-central placentation is found in
Correct Answer: (a)
Dianthus and Primrose exhibit free-central placentation.
Q70. During cell growth, DNA synthesis takes place in
Correct Answer: (a)
Replication of DNA occurs during the Synthesis (S) phase of the cell cycle.
Q71. Select the wrong statement.
Correct Answer: (b)
Pili and fimbriae are involved in attachment; flagella are involved in motility.
Q72. Which of the following National Parks is home to the famous musk deer or hangul?
Correct Answer: (d)
Hangul is found specific to Dachigam.
Q73. DNA-dependent RNA polymerase catalyzes transcription on one strand of the DNA which is called the
Correct Answer: (a)
The mRNA is synthesized on the template strand.
Q74. Which one of the following generates new genetic combinations leading to variation?
Correct Answer: (c)
Meiosis and fertilization in sexual reproduction lead to recombination and variation.
Q75. Which of the following is correct for r-selected species?
Correct Answer: (a)
r-strategists maximize reproductive rate with many small offspring.
Q76. Cortex is the region found between
Correct Answer: (a)
Cortex represents the ground tissue between the epidermis and the stele.
Q77. Which one of the following is wrong for fungi?
Correct Answer: (b)
Fungal cell walls are mainly composed of chitin, not purely cellulose.
Q78. Study the four statements (A-D) given below and select the two correct ones out of them : A. Definition of biological species was given by Ernst Mayr. B. Photoperiod does not affect reproduction in plants. C. Binomial nomenclature system was given by R. H. Whittaker. D. In unicellular organisms, reproduction is synonymous with growth.
Correct Answer: (c)
A and D are correct; B is wrong (photoperiod is vital); C is wrong (Linnaeus).
Q79. Which of the following is Incorrect regarding vasectomy?
Correct Answer: (b)
Sperms are still present in the epididymis; they just can't exit via the duct.
Q80. Among the following edible fishes, which one is a marine fish having rich source of omega-3 fatty acids?
Correct Answer: (d)
Mackerel is a fatty sea fish rich in omega-3.
Q81. Which of the following describes the given graph correctly?
Correct Answer: (b)
Exothermic (product lower than substrate); A is catalyzed activation energy.
Q82. Which of the following rRNAs acts as structural RNA as well as ribozyme in bacteria?
Correct Answer: (c)
23S rRNA acts as the peptidyl transferase ribozyme.
Q83. Radial symmetry is found in the flowers of
Correct Answer: (a)
Brassica (Mustard) has actinomorphic (radial) symmetry.
Q84. The ovule of an angiosperm is technically equivalent to
Correct Answer: (a)
The ovule is synonymous with the megasporangium.
Q85. Which of the following is correctly matched?
Correct Answer: (c)
Parthenium is an invasive species threatening native biodiversity.
Q86. Which one of the following statements is wrong ?
Correct Answer: (b)
Algin is obtained from brown algae (Phaeophyceae) and carrageenan from red algae (Rhodophyceae).
Q87. The chronological order of human evolution from early to the recent is