Metabolism of Carbohydrates MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 22, 2025

1. : The key coenzyme for the activity of muscle glycogen phosphorylase is-
(A) Cyclic AMP
(B) NAD
(C) Pyridoxal phosphate
(D) Coenzyme A

2. : Pyruvate is accumulated in case of the dietary deficiency of vitamin-
(A) Thiamine
(B) Folic acid
(C) Cobalamine
(D) Pyridoxine

3. : Which is correct regarding gluconeogenesis?
(A) In mammals, gluconeogenesis occurs predominantly in the liver
(B) It converts glucose to glycogen
(C) It is glycolysis running in opposite direction
(D) Plants do not undertake gluconeogenesis

4. : Which can be synthesized from pyruvate?
(A) Acetyl CoA
(B) Lactic acid
(C) Ethanol
(D) Both A, B, and C

5. : Glucose 1,6-Bisphosphate is intermediate in _______.
(A) Glycolytic pathway
(B) Gluconeogenesis pathway
(C) Phosphoglucomutase reaction
(D) Glycogen synthetic pathway

6. : Glucose yields how many ATPs by Glycolysis?
(A) 8
(B) 11
(C) 5
(D) 10

7. : The most important regulatory step in glycolysis is-
(A) Formation of fructose-1,6-diphosphate
(B) Formation of glucose-6-phosphate
(C) Formation of fructose-6-phosphate
(D) Formation of glyceraldehydes-3-phosphate

8. : Which of the following is the pathway of conversion of glucose to glycogen?
(A) Glycolysis
(B) Glycogenolysis
(C) Glycogenesis
(D) Gluconeogenesis

9. : Which is correct regarding pyruvate dehydrogenase enzyme?
(A) It converts pyruvate to oxaloacetate
(B) It catalyzes oxidative decarboxylation reaction
(C) It is localized in the cytosol of eukaryotic cells
(D) It requires NADH

10. : The citric acid cycle is an amphibolic pathway, and it can be referred as _____
(A) It is linked to other cycles
(B) It serves in both anabolic and catabolic processes
(C) It can catalyze reactions that are both exergonic and endergonic
(D) It can move in both forward and reverse directions

11. : In which forms is glucose liberated from glycogen?
(A) Glucose-1-Phosphate
(B) Glucose-6-Phosphate
(C) UDP-glucose
(D) Both A, B, and C

12. : The first reaction in citric acid cycle is _______, which generates citrate.
(A) A condensation reaction
(B) An oxidative decarboxylation reaction
(C) Dehydrogenation reaction
(D) A dehydration reaction

13. : Which is correct regarding all the dehydrogenase enzymes that participate in the citric acid cycle?
(A) They catalyze condensation reactions
(B) They generate CO₂
(C) They convert a single bond to a double bond
(D) They generate reduced electron carriers

14. : What role does the coenzyme A play in the citric acid cycle?
(A) It is an acyl group carrier
(B) It carries hydride ions
(C) It is an electron carrier
(D) It is an oxidizing agent

15. : Skeletal muscle does not contribute glucose to blood because:
(A) It lacks the enzyme glycogen phosphorylase
(B) It cannot store glycogen
(C) It lacks the enzyme glucose-6-phosphatase
(D) It lacks the enzyme Phosphoglucomutase

16. : Under which conditions would lactic acid accumulate in skeletal muscle?
(A) When citric acid enzymes are depleted
(B) When O₂ is depleted
(C) When ATP is depleted
(D) When NADH is depleted

17. : Which process does not generate CO₂?
(A) Citric acid Cycle
(B) Conversion of Pyruvate to Lactate
(C) Conversion of Pyruvate to Acetyl CoA
(D) Conversion of Pyruvate to ethanol

18. : A metabolically active cell is in a steady state only if:
(A) The rate of metabolic flow is unchanged
(B) Intermediates are formed and consumed at equal rates
(C) There is no flux
(D) It is at equilibrium with its surroundings

19. : What is the net yield of NADH when 1 mole of glucose-6-phosphate is oxidized by aerobic glycolysis to yield pyruvate?
(A) 2 mole
(B) 1 mole
(C) 0 mole
(D) 4 mole

20. : For every molecule of glucose, how many molecules of CO₂ are released in the citric acid cycle?
(A) Four
(B) Two
(C) One
(D) Six

21. : Amino acids, fatty acids and glucose are oxidized and enter the citric acid cycle as:
(A) Pyruvate
(B) Acetate
(C) Acetyl-CoA
(D) Oxaloacetate

22. : Sugar absorption from the intestine involves:
(A) Active transport
(B) Sodium ions
(C) Na-K ATPase
(D) Both A, B, and C

23. : What is the intracellular site for the operation of glycolysis?
(A) Cytosol
(B) Lysosomes
(C) Endoplasmic reticulum
(D) Mitochondria

24. : What is another name for Glucokinase?
(A) Hexokinase IV
(B) Hexokinase II
(C) Hexokinase III
(D) Hexokinase I

25. : Fructokinase is present in which of the tissues?
(A) Heart
(B) Adipose tissue
(C) Liver
(D) Brain

26. : Which is correct regarding the inter-conversion of nutrients?
(A) Lipids can be converted to amino acids.
(B) Amino acids can be converted to glucose and lipids.
(C) Lipids can be converted to glucose.
(D) Both A, B, and C

27. : Which can be said to act as a carrier of Citric acid cycle?
(A) Acetyl CoA
(B) Ketoglutarate
(C) Oxaloacetate
(D) Malate

28. : Salivary amylase is activated by
(A) Na
(B) Cl
(C) HCO
(D) K

29. : Which statement is correct regarding the conversion of Pyruvate to Acetyl-CoA and CO₂?
(A) It reversible
(B) Requires Lipoic Acid
(C) Occurs in the cytosol
(D) Both A, B, and C

30. : The pentose phosphate pathway serves as a source for each of the following except:
(A) Ribose-5-phosphate
(B) NADPH
(C) ATP
(D) 6-phosphogluconic acid

31. : Glycogen in muscle serves as _____.
(A) a source of fuel for ATP synthesis within that tissue
(B) primarily as a buffer of blood glucose levels
(C) a source of blood glucose after phosphatase action on Glu-6-p
(D) is rapidly synthesized during fasting

32. : Glycolysis of Glucose, under anaerobic conditions, yields how many ATPs?
(A) 6
(B) 2
(C) 8
(D) 10

33. : Glucose-6-phosphatase is absent from which tissues?
(A) Kidney
(B) Intestine
(C) Brain
(D) Heart