Q12. Emerson’s enhancement effect and Red drop have been instrumental in the discovery of :
Correct Answer: (b)
These effects proved that two photosystems work in tandem.
Q13. Select the incorrect statement :
Correct Answer: (c)
Gonadotropins (LH/FSH) increase, not decrease, during the follicular phase.
Q14. Joint Forest Management Concept was introduced in India during :
Correct Answer: (c)
JFM was introduced by the Govt. of India in the 1980s.
Q15. Analogous structures are a result of :
Correct Answer: (b)
Analogous organs arise from convergent evolution due to similar environments.
Q16. Which of the following is not a feature of the plasmids ?
Correct Answer: (d)
Plasmids are double-stranded DNA molecules.
Q17. Photosensitive compound in human eye is made up of :
Correct Answer: (b)
Rhodopsin consists of Opsin and Retinal.
Q18. The Avena curvature is used for bioassay of :
Correct Answer: (c)
Avena curvature test is the bioassay for Auxin (IAA).
Q19. Blood pressure in the pulmonary artery is :
Correct Answer: (c)
Arterial pressure is always higher than venous pressure in the same circuit.
Q20. The standard petal of a papilionaceous corolla is also called :
Correct Answer: (c)
The largest posterior petal is the Vexillum (Standard).
Q21. The taq polymerase enzyme is obtained from :
Correct Answer: (a)
Taq polymerase is isolated from the thermophilic bacterium Thermus aquaticus.
Q22. Which one of the following statements is not true ?
Correct Answer: (a)
Tapetum provides nourishment; the endothecium helps in dehiscence.
Q23. A tall true breeding garden pea plant is crossed with a dwarf true breeding garden pea plant. When the F1 plants were selfed the resulting genotypes were in the ratio of :
Correct Answer: (a)
The genotypic ratio of a monohybrid cross is 1:2:1.
Q24. Which part of the tobacco plant is infected by Meloidogyne incognita ?
Correct Answer: (d)
This nematode infects the roots of tobacco plants.
Q25. Which of the following statements is wrong for viroids ?
Correct Answer: (d)
Viroids have RNA of low molecular weight.
Q26. Which of the following is required as inducer(s) for the expression of Lac operon ?
Correct Answer: (c)
Lactose acts as the inducer for Lac operon.
Q27. Which of the following most appropriately describes haemophilia ?
Correct Answer: (b)
Haemophilia is an X-linked recessive genetic disorder.
Q28. In meiosis crossing over is initiated at :
Correct Answer: (a)
Crossing over occurs during the Pachytene stage of Prophase I.
Q29. Mitochondria and chloroplast are : (a) semi-autonomous organelles. (b) formed by division of pre-existing organelles and they contain DNA but lack protein synthesizing machinery. Which one of the following options is correct ?
Correct Answer: (c)
Organelles have their own DNA and ribosomes (machinery).
Q30. Tricarpellary, syncarpous gynoecium is found in flowers of :
Correct Answer: (a)
Liliaceae typically has a tricarpellary syncarpous ovary.
Q31. In which of the following, all three are macronutrients ?
Correct Answer: (d)
Nitrogen and phosphorus are macronutrients; official key marks this as a bonus/4.
Q32. In a chloroplast the highest number of protons are found in :
Correct Answer: (b)
Protons accumulate in the lumen of thylakoids during light reaction.
Q33. A complex of ribosomes attached to a single strand of RNA is known as :
Correct Answer: (a)
A string of ribosomes on mRNA is called a polysome or polyribosome.
Q34. The two polypeptides of human insulin are linked together by :
Correct Answer: (d)
Human insulin has two peptide chains (A and B) linked by disulphide bridges.
Q35. Match the terms in Column I with their description in Column II and choose the correct option :
(a) Dominance
(i) Many genes govern a single character
(b) Codominance
(ii) In a heterozygous organism only one allele expresses itself
(c) Pleiotropy
(iii) In a heterozygous organism both alleles express themselves fully
(d) Polygenic inheritance
(iv) A single gene influences many characters
Correct Answer: (b)
Correct biological definitions of inheritance patterns.
Q36. The coconut water from tender coconut represents :
Correct Answer: (d)
Tender coconut water is free-nuclear endosperm.
Q37. In mammals, which blood vessel would normally carry largest amount of urea ?
Correct Answer: (c)
Urea is produced in the liver and exits via the hepatic vein.
Q38. Which is the National Aquatic Animal of India ?
Correct Answer: (b)
The Gangetic River Dolphin is the national aquatic animal.
Q39. Spindle fibres attach on to :
Correct Answer: (b)
Spindle fibres attach to the kinetochore protein discs.
Q40. Which of the following is wrongly matched in the given table ?
Microbe
Product
Application
(1) Trichoderma
Cyclosporin A
immunosuppressant
(2) Monascus
Statins
lowering cholesterol
(3) Streptococcus
Streptokinase
removal of clot
(4) Clostridium
Lipase
removal of oil stains
Correct Answer: (d)
Lipase is produced by Candida or Aspergillus; Clostridium is used for Butyric acid.
Q41. In higher vertebrates, the immune system can distinguish self-cells and non-self. If this property is lost due to genetic abnormality and it attacks self-cells, then it leads to :
Correct Answer: (c)
Loss of self-recognition leads to auto-immune diseases.
Q42. Changes in GnRH pulse frequency in females is controlled by circulating levels of :
Correct Answer: (a)
Ovarian steroids provide feedback to the hypothalamus.
Q43. Which of the following features is not present in the Phylum - Arthropoda ?
Correct Answer: (c)
Parapodia are found in Annelida, not Arthropoda.
Q44. A system of rotating crops with legume or grass pasture to improve soil structure and fertility is called :
Correct Answer: (a)
Ley farming improves soil structure by rotating with grass/legumes.
Q45. Pick out the correct statements : (a) Haemophilia is a sex-linked recessive disease. (b) Down's syndrome is due to aneuploidy. (c) Phenylketonuria is an autosomal recessive gene disorder. (d) Sickle cell anaemia is an X - linked recessive gene disorder.
Correct Answer: (d)
Sickle cell is autosomal, not X-linked. a, b, c are correct.
Q46. Which of the following characteristic features always holds true for the corresponding group of animals ?
(1) Cartilaginous endoskeleton
Chondrichthyes
(2) Viviparous
Mammalia
(3) Mouth with upper/lower jaw
Chordata
(4) 3-chambered heart
Reptilia
Correct Answer: (a)
Chondrichthyes always have cartilaginous skeletons. Other groups have exceptions (e.g., Platypus is oviparous).
Q47. Fertilization in humans is practically feasible only if :
Correct Answer: (b)
Transport must be simultaneous to the ampullary-isthmic junction.
Q48. Proximal end of the filament of stamen is attached to the :
Correct Answer: (d)
Filaments attach to the thalamus or the petals in epipetalous flowers.
Q49. Microtubules are the constituents of :
Correct Answer: (b)
Microtubules make up the cytoskeleton of spindle fibers, cilia, and centrioles.
Q50. Which of the following guards the opening of hepatopancreatic duct into the duodenum ?
Correct Answer: (d)
The Sphincter of Oddi regulates the flow of bile and pancreatic juice into the duodenum.
Q51. Asthma may be attributed to :
Correct Answer: (b)
Asthma is an allergic response causing bronchospasm.
Q52. Which one of the following statements is wrong ?
Correct Answer: (c)
Eubacteria are 'true' bacteria, not false bacteria.
Q53. Identify the correct statement on 'inhibin' :
Correct Answer: (b)
Inhibin is produced by granulose cells (females) or Sertoli cells (males) and inhibits FSH.
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