Enzyme NEET Questions and Answers with FREE Pdf Download

ENZYME NEET questions is the most important part of NEET exam 2021 as it contains total 25 marks and carry good weightage. Here we have discussed enzyme  NEET question which gives you a complete idea about type of questions that will be asked in evolution NEET exam. So just prepare enzyme  NEET questions and make sure you qualify NEET exam in your 1st attempt.

Table of Contents

Enzyme NEET Questions and Answers with FREE Pdf Download

1. The organic compounds which serve as cofactors are called 

(2) coenzymes 

(1) apoenzymes 

(3) holoenzymes 

(4) supressors 

2. Enzymes are mostly 

(1) organic catalysts 

(2) inorganic substances 

(3) compounds which speed up the rate of reaction 

(4) all of the above 

3. An apoenzyme is a: 

(1) vitamin 

(2) amino acid 

(3) carbohydrate  

(4) protein 

4. Induced fit model to explain the mechanism of enzyme action was given by 

(1) Buchner 

(2) Sumner 

(3) Kosh land 

(4) Fisher 

5. Enzymes having different molecular forms but the same specificity are 

(1) isoenzymes 

(2) allosteric enzymes 

(4) holoenzyme 

(3) coenzymes 

6.  Which one of the following is a coenzyme? 

(1) Fe++ 

(2) NAD 

(3) Ligase 

(4) Lyases 

7. Feedback inhibition is caused by blocking enzymatic reactions when 

(1) enzyme is denatured 

(2) pH is changed 

(3) end products accumulate 

(4) activation energy is increased 

8. Competitive inhibition is due to 

(1) addition of substrate 

(2) substrate analogue 

(3) inhibition due to change in optimal condition 

(4) competition for active sites by a substrate 

9. Enzyme catalysing rearrangement of atomic groupings without altering molecular weight or number of atoms is 

(1) ligase 

(2) isomerase 

(4) hydrolase 

(3) oxidoreductasee 

10. An enzyme acts by 

(1) reducing the energy of acti vation 

(2) increasing the energy of activation 

(3) decreasing the pH 

(4) increasing the pH 

11. Enzymes are the polymers of 

(2) fatty acids 

(1) hexose carbon 

(3) amino acids 

(4)inorganic phosphates 

12. The enzyme synthesized for the first time was 

 (2) insulin 

(1) urcase 

(4) zymase 

(3) diastase 

13. Coenzym FMN and FAD are derived from vitamin 

(4) B2 

(3) B 

(1) C 

(2) B6 

14. NADP is 

(2) an enzyme 

(1) a coenzyme 

(3) part of tRNA 

(4) part of rRNA  

15. Blocking of enzyme action by blocking its active sites is: 

(1) allosteric inhibition 

(2) feedback inhibition 

(3) competitive inhibition 

(4) non-competitive inhibition 

16. Enzymes functional inside the cells are called 

(1) endoenzymes 

(2) exoenzymes 

(3) apoenzymes 

(4) isoenzymes 

17. Inorganic cofactor is often referred to as 

(1) modulator 

(2) activator 

(3) prosthetic group  

(4) coenzyme 

18. The ratio of the enzymes to substrate molecules can be as high as 

(1) 1 1000 

(2) 1 100,000 

(3) 1 1,000,000  

(4) 1 50,000 

19. The fastest acting enzyme in the biological world is 

(1) amylase 

(2) lipase 

(3) carboxypeptidase  

(4) carbonic anhydrase 

20. A co-enzyme is 

(1) an inorganic compound 

(2) often a metal 

(3) a protein 

(4) a vitamin 

21. Which is a typical example of feedback inhibition? 

(1) Allosteric inhibition of hexokinase by glucose-6-phosphate 

(2) Reaction between succinic dehydrogenase and succinic acid 

(3) Cyanide and cytochrome reaction 

(4) Sulpha drugs and folic acid synthesis in bacteria 

22. An allosteric compound is 

(1) an enzyme 

(2) a substance which regulates enzyme activity 

(3) a non-enzyme compound which acts like an enzyme 

(4) an apoenzyme 

23. With every 10°C rise in temperature, the rate of an enzymatic reaction of

(2) becomes half 

(1) doubles 

(3) becomes four times 

(4) remains same 

24. Who is credited to crystalise urease enzyme ? 

(1) Thompson  

(2) Kuhne 

(4) Sumner 

(3) Garnier 

25. In competitive inhibition, which of the following is true ? 

(1) E + I = El (( inhibitor, E = nzyme) 

(2) E+ I = El + ES = SI (S = substrate) 

(4) none of the above 

(3) ES + I = ESI 

26. Reaction between an enzyme and a substrate is 

(2) irreversible 

(1) reversible 

(3) both (1) and (2)  

(4) none of the above 

27. The function of enzyme is to 

(1) change equilibrium 

(2) cause biochemical reactioon 

(3) change the rate of biochemical reaction 

(4) all the above 

28. The enzyme anylase hydrolyses starch into 

(2) glucose 

(1) maltose 

(3) dextrose 

(4) glucose and fructose 

29, In ‘feedback inhibition’ a metabolic pathway is switched off by 

(1) rise in temperature 

(2) lack of substrate 

(3) accumulation of end product 

(4) competitive inhibition 

30. Inactive precursors of enzymes are called: 

(2) isoenzymes 

(1) co-enzymes 

(4) apoenzymes 

(3) zymogens 

31. Esterase belongs to the category of 

(1) carboxylating enzyme 

(2) hydrolytic-enzyme 

(3) oxidation reduction enzyme 

(4) dehydrogenase enzyme 

32. Enzymes concerned with the transfer of electrons are 

(1) hydrolase 

(2) dehydrogenase 

(3) transaminase 

(4) desmolase 

33. For which of the following enzymes, the substrate is also an enzyme 

(1) Enterokinase 

(2) Glycogen phosphorylase kinase 

(3) Glycogen phosphorylase phosphatase 

(4) All the above 

34. The enzymes which have similar action but may be isolated from different sources are known as 

(1) homologous isozymes 

(2) analogous isozymes 

(3) isomorphs 

(4) coenzymes 

35. The coenzyme NAD and FAD are 

(1) vitamins 

(2) nucleotides 

(3) reducing agents 

(4) conjugates of nucleotides with vitamins 

36. Enzymes occur in the cell in the form of 

(1) solution 

(2) colloids 

(3) crystals 

(4) suspended particles 

37. Zymogens are 

(1) group of zymase enzymes 

(2) inactive enzyme precursos 

(3) enzyme acting upon starch 

(4) none of the above 

38.of two strands of An enzyme that joins the ends nucleic acid is : 

(2) ligase 

(1) polymerase 

(4) helicase 

(3) synthetase 

39. If corn is immersed after harvest in the boiling water and cooled, the sweetness remains the same because 

(1) polysaccharide is reconverted into soluble sugars 

(2) concentration of sugar increases due to heating 

(3) conversion of sugars to polysaccharides stops 

(4) enzymes responsible for the conversion are destroyed 

40. Most of the members of vitamin B complex act as 

(1) cofactor 

(2) coenzyme 

(3) prosthetic group  

(4) apoenzyme 

41. Which of the following are co-enzymes? 

(1) NAD, NADPH2, Cobalt 

(2) NAD, NADP, FAD, FMN 

(3) Vitamins, iron, copper 

(4) NAD, potassium, CoA 

42. A protein subjected to an electric field may show the separation of its fractions into 

(1) apoenzyme and coenzyme 

(2) active site and allosteric site 

(3) protein and non-protein fractions 

(4) isoenzymes 

43. Which one of the following are considered ‘teeth of an enzyme? 

(1) Coenzyme 

(2) Apoenzyme 

(3) Isoenzyme 

(4) Holoenzyme 

44. Which of the following contains copper 

1) Quinone 

(2) Plastoquinone 

(3) Plastocyanin 

(4) None of these 

45. In which of the following organisms enzyme are absent ? 

(1) Fungi 

(2) Viruses 

(3) Algac 

(4) Bacteria 

46. The enzyme resposible for the reduction molecular nitrogen to the level of ammonia the leguminous root nodule is 

(1) nitrogenase 

(2) nitrate reductase 

(3) nitrite reductase  

(4) all of the abovc 

47. An example of competitive hibition of an me is the inhibit of  

(1)succinic dehydrogenase by malonic acid 

(2) cytochrome oxidase by cyanide 

(3) hexokinase by glucose -6-phosphate 

(4) carbonic anhydrase by carbon dioxide 

48. An organic substance bound to an enzyme and essential for its activity is called 

(2) apoenzyme 

(1) holoenzyme 

(4) coenzyme 

(3) isoenzyme 

49. Digestive enzymes are 

(2) Tranferases 

(1) Hydrolases 

(3) Oxidoreductases  

(4) Ligases 

50. Which one is not added in detergents ? 

(2) Protease 

(1) Amylase 

(4) Cellulase 

(3) Peptidase 

51. A metal ion required for normal functioning of an enzyme is 

(2) Coenzyme 

(1) Holoenzyme 

(3) Cofactor 

(4) Prosthetic group 

52. “Lock and Key” model of enzyme action illustrates that a particular enzyme molecule 

(1) is destroyed and resynthesised several times 

(2) Reacts at the same rate in all conditions 

(3) Interacts with specific type of substrate molecule 

(4) Forms a permanent enzyme-substrate complex 

53. All enzymes are proteins”. This statement is now modified because of exception to this 

(1) Arylasulphatase  

(2) Ribozyme 

(3) Nitroreducatase 

(4) Dehydrogenase 

54. Three of the following statements about enzymes are correct and one is wrong. Which one is wrong? 

(1) Enzymes are denatured at high temperature but in certain exceptional organisms they are effective even at 80°-90°C 

(2) Enzymes require optimum pH for maximal activity 

(3) Most enzymes are proteins but some are lipids 

(4) Enzymes are highly specific 

55. Organic prosthetic group of  

(1) Protin 

(2) coenzyme 

(3) an enzymes 

(4) apoenzymes 

56. Thermolabile protein part of enzyme is called 

(1) proenzyme 

(2) holoenzyme 

(3) apoenzyme 

(4) isoenzyme 

57. The essential chemical components of many coenzymes are 

(1) Nucleic acids 

(2) Carbohydrates 

(3) Vitamins 

(4) Proteins 

58. Transition state structure of the substrate formed during an enzymatic reaction is  

(1) permanent but unstable 

(2) transient and unstable 

(3) permanent and stable 

(4) transient but stable 

59. Which of the following is not correctly matched for the organism and its cell wall degrading enzyme? 

(1) Plant cells Cellulase 

(2) Algae Methylase Chitinase 

(3) Fungi 

(4) Bacteria Lysozyme 

Various questions on enzyme are given in this article. Candidates those who are preparing for NEET 2021-22 and looking for questions on enzymes  they can use these questions.NEET PDF questions answers key for National Eligibility cum Entrance Test (NEET) Exam.

Answer  

1. (2) 2. (1)3. (4) 4. (3) 5. (1) 6. (2) 7. (3)8. (2)9. (2) 10. (1)11. (3) 12. (1) 13. (4) 14. (1) 15. (3) 16. (1) 17. (2) 18. (3)19. (4) 20. (4) 21. (1) 22. (2) 23. (1) 24. (4) 25. (1) 26. (1) 27. (3) 28. (1) 29. (3) 30. (3) 31. (2) 32. (2) 33. (4) 34. (2) 35. (4) 36. (2) 37. (2) 38. (2) 39. (4) 40. (1) 41. (2) 42. (4) 43. (1) 44. (3)45. (2) 46. (1) 47. (3) 48. (4) 49. (1) 50. 3) 51. (3) 52. (3) 53. (2) 54. (3) 55. (3) 56. (3) 57.(3) 58. (2) 59. (2). 

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