41. A three-dimensional cavity bearing a specific charge by which the enzyme reacts with its substrate is called
Active site
Binding site
Catalytic site
Allosteric site
✅ The correct answer is option A.
Biology
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42. Natural extrachromosomal circular DNA molecules carrying genes for antibiotic resistance and fertility
Recombinant DNA
Chimaeric DNA
Lambda phage
Plasmids
✅ The correct answer is option D.
43. Nodules on roots of leguminous plants have _____ bacteria
Anaerobic
Nitrogen fixing
Nitrifying
Ammonifying
✅ The correct answer is option B.
44. Which step causes the activation of the catalytic site of an enzyme?
Change in pH of the surroundings.
Formation of Enzyme Substrate complex.
Change in the charge of the active site.
Change in temperature
✅ The correct answer is option B.
45. Which one has an antibiotic resistance gene for tetracycline and ampicillin?
pSC 101
pBR 322
pCR 322
None of these
✅ The correct answer is option B.
46. Lock and Key model was proposed by
Emil Fischer
Koshland
Robin Williams
Rudolph Virchow
✅ The correct answer is option A.
47. The enzyme which seals the foreign DNA into the vector is
Restriction endonuclease
DNA polymerase
DNA ligase
DNA mutase
✅ The correct answer is option C.
48. In asexual reproduction, offspring are produced by
Meiosis
Mitosis
Both a and b
None of these
✅ The correct answer is option B.
49. Chimaeric DNA is also known as
Recombinant DNA
Complementary DNA
Vector
Plasmid
✅ The correct answer is option A.
50. Which method is of asexual reproduction?
Sporulation
Fission
Apomixis
All of these
✅ The correct answer is option D.