Enzymology (Biochemistry) BSc MCQs Set-3

Biochemistry Mcqs

1.The “A” in coenzyme- A is ———–

(a) Alkylation
(b) Acetylation
(c) Amination
(d) Amino acid

Answer:(b) Acetylation

2.Which of the following statement/s is/are correct?

(a) Enzyme is a biocatalyst
(b) Enzyme increases the rate of reaction
(c) Enzyme decreases the activation energy of the reaction
(d) All the above

Answer:(d) All the above

3.Nature of the enzyme is

(a) Protein
(b) Lipid
(c) Carbohydrate
(d) None

Answer:(a) Protein

4. An enzyme was crystallized for the first time by

(a) John Northrop
(b) Edward Buchner
(c) J.B. Sumner
(d) None

Answer:(c) J.B. Sumner

5. Which of the following is correct?

(a) Apoenzyme + Cofactor = Holoenzyme
(b) Apoenzyme – Cofactor = Holoenzyme
(c) Apoenzyme =Cofactor – Holoenzyme
(d) None

Answer:(a) Apoenzyme + Cofactor = Holoenzyme

6. Enzymes are classified into _____ types

(a) Two
(b) Three
(c) Five
(d) Six

Answer:(d) Six

7. Competitive inhibitor of an enzyme is

(a) Structural analogue of enzyme
(b) Functional analogue of enzyme
(c) Functional analogue of substrate
(d) Structural analogue of substrate

Answer:(d) Structural analogue of substrate

8.Who is the father of enzymology?

(a) Anton van Leeuwenhoek
(b) Edward Howell
(c) JB Sumner
(d) John Northrop

Answer:(d) John Northrop

9. Majority of the enzymes are inactive at

(a) At 25oC
(b) At 15oC
(c) Between 30-40oC
(d) Above 70oC

Answer:(a) At 25oC

10. Induced fit theory for the formation of Enzyme-Substrate complex was proposed by

(a) Koshland
(b) Charles Leibeg
(c) Buchner
(d) Fischer

Answer:(d) Fischer

11. SI Unit for enzyme activity is

(a) Bel
(b) mho
(c) Hertz
(d) Katal

Answer:(b) mho

12. Which of the following is the reason for Gout disease?

(a) Deficiency of Xanthine Oxidase enzyme
(b) Overproduction of Xanthine Oxidase
(c) Deficiency of ß-galactosidase enzyme
(d) Deficiency of Lipase enzyme

Answer:(d) Deficiency of Lipase enzyme

13. Which of these enzymes is related to molecular biology?

(a) DNA Ligase
(b) DNA topoisomerase
(c) Polymerase
(d) All the above

Answer:(a) DNA Ligase

14. Deficiency of the enzyme ß-glucocerebrosidase results in

(a) Gaucher’s Disease
(b) Faber’s disease
(c) Krabbe’s disease
(d) Lesch-Nyhan Syndrome

Answer:(d) Lesch-Nyhan Syndrome

15. Enzyme that differ in amino acid sequence but catalyze the same reaction are_______ 

(a) Co-factors
(b) Co-enzymes
(c) Apo enzymes
(d) Isoenzymes

Answer:(a) Co-factors

16. The temperature at which the maximum activity of the enzyme occurs is

(a) Optimum temperature
(b) Maximum Temperature
(c) Minimum Temperature
(d) None

Answer:(c) Minimum Temperature

17. The class of enzymes that catalyzes synthetic reactions where two molecules are joinedtogether and ATP is used is

(a) Hydrolases
(b) Lyases
(c) Ligases
(d) Isomerases

Answer:(b) Lyases

18. Non-protein organic part of the enzyme is__________ 

(a) Co-factor
(b) Co-enzyme
(c) Apo enzyme
(d) Isoenzyme

Answer:(a) Co-factor

19. Pepsin and urease are examples for which class of enzymes

(a) Hydrolases
(b) Ligases
(c) Oxidoreductases
(d) Lyases

Answer:(d) Lyases

20. Which of the following enzymes is elevated in alcoholism

(a) Hepatitis
(b) Serum Glutamate Pyruvate Transmittance
(c) Acid Phosphatase
(d) glutamyl transpeptidase

Answer:(d) glutamyl transpeptidase

21.The coenzyme of Nicotinic acid is —— 

(a) FMN
(c) NAD

Answer:(c) NAD

22.Pantothenic acid is also known as ——- 

(a) Coenzyme- A
(c) Nicotinamide
(d) TH4

Answer:(a) Coenzyme- A

23.In competitive inhibition Vmax——- 

(a) Increases
(b) Decreases
(c) Remaining unchanged
(d) None of above

Answer:(c) Remaining unchanged

24.The detergent SDS is used in —— 

(a) Chromatography
(c) Electrophoresis
(d) All of the above. 

Answer:(c) Electrophoresis

25.Biochemically active form of folic acid is ——- 

(a) TPP
(b) TH4′ 
(c) FMN

Answer:(b) TH4′

26.The ideal example of isoenzyme is —— 

(a) ATcase. 
(c) LDH

Answer:(c) LDH

27.——–is the 1sl member of vitamin-B family

(a) Folic acid
(b) Thiamine
(c) Biotin

Answer:(b) Thiamine

28.——-is the inhibitor of ATcase. 

(a) ATP
(c) GTP

Answer:(c) GTP

29.The “A” is coenzyme-.A is —- 

(a) Acetylation
(b) Alkylation

Answer:(a) Acetylation

30.Biochemically active form of riboflavin is —–

(a) FMN
(b)Both a & c
(c) FAD
(d)None of above

Answer:(b)Both a & c

31.The active form of vitamin folic acid is ———- 

(a) Tetrahydrofolate
(b) Glutamic Acid
(c) Dihydrofolate
(d) Pteridine Residue

Answer:(a) Tetrahydrofolate

32.The biochemical function of coenzyme A is ————– 

(a) To carry hydroxyl l groups
(b) To carry hydrogen atoms
(c) To carry acetyl groups
(d) To carry water molecule

Answer:(c) To carry acetyl groups

33.The symptom(s) of biotin deficiency are————– 

(a) Anemia
(b) Loss of appetite
(c) Nausea
(d) All of the above

Answer:(d) All of the above

34.———-vitamin serves as carrier of C02 in carboxylation reactions. 

(a) Niacin
(b) Thiamine
(c) Folic Acid
(d) Biotin

Answer:(d) Biotin

35.The Coenzyme PLP is associated with —-metabolism. 

(a) Nucleic acid
(b) Amino acid
(c) Lipid
(d) Carbohydrate

Answer:(b) Amino acid

36.Coenzyme A is also known as ———-. 

(a) Riboflavin
(b)Folic acid
(c) Thiamine
(d)Pantothenic acid

Answer:(d)Pantothenic acid

37.The value of Km increases in ———–inhibition. 

(a) Non-competitive
(c) Competitive

Answer:(c) Competitive

38.The ————–chromatography is based on molecular size. 

(a) Affinity
(b)Gel exclusion
(c) Thin layer

Answer:(b)Gel exclusion

39.The enzyme possess additional site beside active site is ———–

(a) Catalytic site
(b)Both a & b
(c) Allosteric site
(d)None of the above

Answer:(c) Allosteric site

40.The coenzyme(s) of riboflavin is / are ———- 

(a) FAD
(b)Both a & c
(c) FMN

Answer:(b)Both a & c

41.Which of the following is the deficiency disease of thiamine?

(a) Cheilosis
(b) Beriberi
(c) Glossitis

Answer:(b) Beriberi

42.The coenzyme of nicotinic acid is ———– 

(a) FAD
(b) TPP
(c) NAD

Answer:(c) NAD

43.In non-competitive inhibition, the Km value is ——— 

(a) Unchanged
(c) Increases
(d)None of above

Answer:(a) Unchanged

44.The ideal example of isoenzyme is ———– 

(a) PDH
(c) PFK
(d)AT Case


45.The detergent SDS is used in ———– 

(a) Centrifugation
(c) Electrophoresis
(d)None of above

Answer:(c) Electrophoresis

46.lodoacetate is an example of ——– inhibitor of enzymes. 

(a) Reversible
(c) Allosteric
(d) All of above

Answer:(a) Reversible

47.The active form of vitamin nicotinic acid is I are ———- 

(a) NAD+
(c) Both (a) & (b)
(d) ‘None of above

Answer:(c) Both (a) & (b)

48.is the inhibitor of ATCase. 

(a) ATP
(c) GTP


49.The biochemical function of pantothenic acid is ——-. 

(a) Transfer of acyl group
(b) Transfer of Hydrogens
(c) Transfer of amino group
(d) Transfer of alkyl group

Answer:(a) Transfer of acyl group

50.———-is the deficiency disease of vitamin nicotinic acid. 

(a) Beriberi
(b) Glossitis
(c) Pellagra
(d) Anemia

Answer:(c) Pellagra