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FEBRUARY ’1336. The enzyme used in polymerase chain reaction (PCR) is (a) Taq polymerase (b) RNA polymerase (c) ribonuclease (d) endonuclease.
37. The genetically-modified (GM) brinjal in India has been developed for
(a) insect-resistance (b) enhancing shelf life (c) enhancing mineral content
(d) drought-resistance. 38. Satellite DNA is useful tool in
(a) organ transplantation
(b) sex determination (c) forensic science (d) genetic engineering.
39. Which of the following is not used as bioweapon? (a) Bacillus anthracis (b) Botulinum toxin (c) Bacillus thuringiensis toxin
(d) Smallpox.
40. Bacillus thuringiensis forms protein crystals which contain insectidical protein. This protein
(a) binds with epithelial cells of midgut of the insect pest ultimately killing it
(b) is coded by several genes including the gene cry (c) is activated by acid pH of the foregut of the insect
pest
(d) does not kill the carrier bacterium which is itself resistant to this toxin.
41. The term “molecular scissors” generally refers to (a) DNA polymerases
(b) RNA polymerases (c) restriction endonucleases (d) DNA ligases.
42. The purpose of polymerase chain reaction is (a) DNA modification (b) DNA amplification (c) DNA replication (d) DNA visualization. 43. Plasmids are
(a) extra chromosomal DNA which can self replicate (b) DNA carrying genetic sequence, without expressing
it
(c) integrated within host DNA without replication ability
(d) none of these.
44. Consumption of which one of the following foods can prevent the kind of blindness associated with vitamin ‘A’ deficiency?
(a) ‘Flavr Savr’ tomato (b) Canolla (c) Golden rice (d) Bt-Brinjal.
45. For transformation, micro-particles coated with DNA to be bombarded with gene gun are made up of
(a) silver or platinum (b) platinum or zinc (c) silicon or platinum (d) gold or tungsten.
46. Tobacco plants resistant to a nematode have been
developed by the introduction of DNA that produces (in the host cells)
(a) both sense and anti-sense RNA (b) a particular hormone
(c) an antifeedant (d) a toxic protein.
47. Which one of the following represents a palindromic sequence in DNA?
(a) 5′ - GAATTC - 3′ (b) 5′ - CCAATG - 3′ 3′ - CTTAAG - 5′ 3′ - GAATCC - 5′ (c) 5′ - CATTAG - 3′ (d) 5′ - GATACC - 3′ 3′ - GATAAC - 5′ 3′ - CCTAAG - 5′
48. Read the two statements A and B and identify the correct circle from those given below.
Statement A : Agrobacterium tumefaciens is the causative agent of crown gall disease of dicots.
Statement B : Agrobacterium tumefaciens causes infection by entering the plant through wounds and injuries. (a) Statement A is correct and B is wrong. (b) Statement B is correct and A is wrong. (c) Both statements A and B are correct. (d) Both statements A and B are wrong.
49. The usual source of restriction endonucleases used in gene cloning is
(a) fungi (b) bacteria (c) plants (d) viruses. 50. Gel electrophoresis is used for the
(a) separation and isolation of DNA fragments
(b) construction of recombinant DNA by joining with cloning vectors
(c) culturing the host cells in a medium at a large scale (d) replication of DNA for many times
51. RNA interference is essential for the (a) cell proliferation (b) cell defence (c) cell differentiation (d) micropropagation. 52. The figure below shows three steps (A, B, C) of Polymerase
Chain Reaction (PCR). Select the option giving correct identification together with what it represents?
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FEBRUARY ’13 87B O O K S
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FEBRUARY ’13(a) B - denaturation at a temperature of about 98°C separating the two DNA strands.
(b) A - denaturation at a temperature of about 50°C. (c) C - extension in the presence of DNA polymerase. (d) A - annealing with two sets of primers.
53. The Bt toxin is not toxic to human beings because (a) the pro Bt toxin activation requires temperature above
human body temperature.
(b) the Bt toxin recognizes only insect-specific targets. (c) the Bt toxin formation from pre Bt toxin requires pH
lower than that present in human stomach.
(d) conversion of pro Bt toxin to Bt toxin takes place only in highly alkaline conditions.
54. The thermostable enzymes, ‘Taq’ and ‘Pfu’, isolated from thermophilic bacteria are
(a) RNA polymerases (b) DNA polymerases (c) restriction endonucleases
(d) DNA ligases.
55. Bt brinjal is an example of transgenic crops. In this, Bt refers to
(a) Bacillus tuberculosis (b) biotechnology (c) b carotene (d) Bacillus thuringiensis. 56. Which of the following is not correct statement about the
plasmids ?
(a) It is the extra chromosomal DNA in bacteria. (b) It is not an integral part but inert genetic material. (c) Host chromosome can be integrated with the
plasmid.
(d) Transfer of plasmid can be done from cell to cell without killing the host.
57. Stirred-tank bioreactors have been designed for (a) addition of preservatives to the product (b) purification of the product
(c) ensuring anaerobic conditions in the culture vessel (d) availability of oxygen throughout the process. 58. Plants in comparison to animals are more rapidly
manipulated by genetic engineering. Select out the most probable reason for this
(a) totipotency shown by plant cells
(b) single somatic cell can regenerate a whole plant body
(c) genetic engineering is supplemented with plant tissue culture techniques
(d) all of the above.
59. The technique in which foreign DNA is precipitated over surface of metal particles for passing into target cells is (a) microinjection
(b) electroporation (c) particle gun
(d) chemical mediated gene transfer.
60. Insulin has 51 amino acids arranged in (a) single polypeptide
(b) two polypeptides of 21 and 30 amino acids (c) two polypeptides of 25 and 26 amino acids
(d) three polypeptides having 15, 16 and 20 amino acids.
61. Crown gall disease in plants is caused by (a) Ti plasmid (b) Pi plasmid (c) bacteria (d) virus.
62. Two microbes found to be very useful in genetic engineering are
(a) crown gall bacterium and Caenorhabditis elegans (b) Escherichia coli and Agrobacterium tumefaciens (c) Vibrio cholerae and a tailed bacteriophage (d) Diplococcus sp. and Pseudomonas sp.
63. Human insulin is being commercially produced from a transgenic species of
(a) Rhizobium (b) Saccharomyces (c) Escherichia (d) Mycobacterium.
64. In transgenics, expression of transgene in target tissue is determined by
(a) enhancer (b) transgene (c) promotor (d) reporter. 65. Recombinant DNA technology is related with
(a) C. Darwin (b) Stanley Cohen (c) Herbert Boyer (d) Both (b) and (c). 66. Transgenic crop contains
(a) gene for resistance to antibiotics (b) protein produced by the gene
(c) enzymes produced by the gene for antibiotics (d) all of the above.
67. cDNA is
(a) formed by reverse transcriptase (b) cloned DNA
(c) circular DNA (d) recombinant DNA. 68. Electroporation involves
(a) promotion of seed germination by induced imbibition of water with electric current
(b) making transient pores in cell membrane to facilitate entry of gene constructs
(c) purification of saline water with the help of an artificial membrane
(d) passage of sucrose through sieve pores by electroosmosis.
69. Restriction endonuclease enzyme cuts (a) any fragment of DNA
(b) (+) fragment of DNA (c) (–) fragment of DNA (d) double helical DNA.
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FEBRUARY ’13 89 70. The two main vectors used in genetic engineering to carrygenes into bacteria are
(a) plasmids and bacteriophages (b) plastids and plasmids (c) plastids and bacteriophages (d) plasmids and phasmids.
71. Plant cells can be converted to protoplasts by treating them with
(a) cellulase
(b) cellulase + pectinase (c) cellulase + pectinase + lipase
(d) cellulase + pectinase + lipase + protease. 72. Gene therapy involve
(a) introduction of a normal genes in cell (b) treating of defective genes with radiation (c) eliminating defective and useless genes (d) replacement of defective genes by normal one. 73. The separated DNA fragments can be visualized with a
compound known as
(a) lysozyme (b) agarose gel (c) ethidium bromide (d) Ti plasmid
74. Which of the following is a palindromic sequence? (i) HANNAH (ii) TESTREST
(iii) SEXES (iv) MUNMUN (a) (i) and (iii) (b) (ii) and (iv) (c) (i), (iii) and (iv) (d) all of these
75. Transformation procedure can be identified with the help of selectable markers which are
(a) origin of replication genes (b) recognition sites
(c) cloning sites
(d) antibiotic resistance genes
76. DNA ligase form ‘X’ between adjacent nucleosides and covalently link two individual fragments of double – stranded DNAs. What is ‘X’?
(a) Phophodiester bonds (b) Hydrogen bonds (c) Disulphide bonds (d) Glycosidic bonds
77. Attempts are being made to produce useful biological products for the treatment of which of these diseases? (a) Phenylketonuria (b) Cystic fibrosis
(c) Emphysema (d) All of these.
78. Read the steps involved in the technique of ELISA and arrange these steps in correct sequence.
(i) Unreacted anti-Ig is washed away.
(ii) Antigen of interest immobilized on the surface Petriplate.
(iii) Anti-Ig binds to Ag-Ab complex.
(iv) Unreacted molecules of Ag-Ab complex are washed away.
(v) Antibody specific to the Ag reacts with it.
(vi) substrate is added to react with enzyme conjugated with anti-Ig.
(a) (ii), (v), (iv), (iii), (i), (vi) (b) (ii), (iv), (v), (iii), (i), (vi) (c) (iv), (v), (ii), (vi), (iii), (i) (d) (ii), (v), (iv), (i), (iii), (vi)
79. Which of the following is not the application of transgenic animals?
(a) Developing animals specially created for use in xenografting.
(b) Molecular diagnosis of pathogens such as detecting presence of antigens, their proteins or glycoproteins, etc.
(c) To test genetically engineered hormones to increase milk yield, meat production, etc.
(d) To test pharmaceutical proteins,, drugs production etc.
80. The Ti plasmid of Agrobacterium tumifaciens has now been modified into a cloning vector after ‘disarming’ it. Which property of it is useful as a cloning vector?
(a) It delivers genes of interest into a variety of plants. (b) It possesses sites for insertion of foreign gene which
is to be introduced.
(c) It possesses selectable markers. (d) All of these.
Answer keY
1. (d) 2. (c) 3. (c) 4. (b) 5. (c) 6. (a) 7. (c) 8. (b) 9. (b) 10. (c) 11. (b) 12. (d) 13. (b) 14. (c) 15. (d) 16. (d) 17. (d) 18. (b) 19. (a) 20. (c) 21. (a) 22. (a) 23. (a) 24. (c) 25. (a) 26. (c) 27. (a) 28. (d) 29. (c) 30. (d) 31. (c) 32. (a) 33. (a) 34. (c) 35. (c) 36. (a) 37. (a) 38. (c) 39. (c) 40. (a) 41. (c) 42. (b) 43. (a) 44. (c) 45. (d) 46. (a) 47. (a) 48. (c) 49. (b) 50. (a) 51. (b) 52. (a) 53. (d) 54. (b) 55. (d) 56. (b) 57. (d) 58. (d) 59. (c) 60. (b) 61. (a) 62. (c) 63. (c) 64. (d) 65. (d) 66. (d) 67. (a) 68. (b) 69. (d) 70. (a) 71. (b) 72. (d) 73. (c) 74. (a) 75. (d) 76. (a) 77. (d) 78. (a) 79. (b) 80. (d) nnWorldMags.net
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