Nutritional Biochemistry MCQs 50 Score: 0 Attempted: 0/50 Subscribe 1. : Which of the following is the main storage form of carbohydrates in animals? (A) Starch (B) Glycogen (C) Cellulose (D) Glucose Show All Answers 2. : Enzymes that speed up biochemical reactions are mainly composed of: (A) Lipids (B) Proteins (C) Vitamins (D) Minerals 3. : Which vitamin acts as a coenzyme in carbohydrate metabolism? (A) Vitamin Bβ (Thiamine) (B) Vitamin A (C) Vitamin D (D) Vitamin K 4. : The end product of glycolysis is: (A) Glucose (B) Pyruvate (C) Lactate (D) Acetyl-CoA 5. : Which biomolecule provides the highest energy per gram? (A) Carbohydrates (B) Proteins (C) Fats (D) Vitamins 6. : The urea cycle primarily occurs in which organ? (A) Kidney (B) Liver (C) Pancreas (D) Intestine 7. : Which vitamin is a cofactor for collagen synthesis? (A) Vitamin D (B) Vitamin C (C) Vitamin E (D) Vitamin K 8. : The process of converting glucose to glycogen is called: (A) Glycolysis (B) Glycogenesis (C) Gluconeogenesis (D) Glycogenolysis 9. : The biochemical breakdown of fats produces: (A) Glycerol and fatty acids (B) Amino acids (C) Monosaccharides (D) Alcohols 10. : Which enzyme catalyzes the conversion of starch to maltose? (A) Lipase (B) Amylase (C) Pepsin (D) Trypsin 11. : The TCA cycle occurs in the: (A) Cytoplasm (B) Nucleus (C) Mitochondria (D) Endoplasmic reticulum 12. : Which of the following is a ketogenic amino acid? (A) Lysine (B) Alanine (C) Glycine (D) Serine 13. : NADβΊ functions as a: (A) Substrate (B) Coenzyme in redox reactions (C) Structural protein (D) Hormone 14. : The process of glucose synthesis from non-carbohydrate sources is known as: (A) Glycolysis (B) Gluconeogenesis (C) Fermentation (D) Glycogenolysis 15. : The enzyme lipase helps in the digestion of: (A) Proteins (B) Fats (C) Carbohydrates (D) Vitamins 16. : The oxidation of one molecule of glucose yields approximately: (A) 2 ATP (B) 18 ATP (C) 36β38 ATP (D) 10 ATP 17. : Which of the following is a water-soluble vitamin? (A) Vitamin D (B) Vitamin K (C) Vitamin C (D) Vitamin E 18. : What is the main nitrogenous waste product in humans? (A) Ammonia (B) Uric acid (C) Urea (D) Creatinine 19. : The enzyme responsible for breaking down proteins into peptides is: (A) Pepsin (B) Amylase (C) Lipase (D) Maltase 20. : Beta-oxidation of fatty acids occurs in the: (A) Cytosol (B) Mitochondria (C) Nucleus (D) Ribosome 21. : The main function of insulin is to: (A) Decrease blood glucose (B) Increase blood glucose (C) Digest fats (D) Store protein 22. : Which vitamin acts as a coenzyme in amino acid metabolism? (A) Vitamin Bβ (Pyridoxine) (B) Vitamin Bββ (C) Vitamin C (D) Vitamin E 23. : The Cori cycle connects which two organs? (A) Liver and muscle (B) Kidney and heart (C) Brain and pancreas (D) Stomach and intestine 24. : The deficiency of Vitamin Bββ causes: (A) Rickets (B) Pernicious anemia (C) Night blindness (D) Scurvy 25. : Which metabolic pathway produces lactic acid during oxygen deficiency? (A) Anaerobic glycolysis (B) Krebs cycle (C) Beta-oxidation (D) Electron transport chain 26. : The enzyme hexokinase catalyzes the: (A) First step of glycolysis (B) Last step of glycolysis (C) ATP synthesis (D) Protein breakdown 27. : The main function of coenzyme Q (ubiquinone) is in: (A) DNA replication (B) Electron transport chain (C) Protein folding (D) Vitamin synthesis 28. : The main lipid found in cell membranes is: (A) Cholesterol (B) Phospholipid (C) Triglyceride (D) Steroid 29. : The conversion of pyruvate to lactate is catalyzed by: (A) Lactate dehydrogenase (B) Pyruvate kinase (C) Hexokinase (D) Amylase 30. : Which mineral acts as a cofactor for many enzymes? (A) Iron (B) Magnesium (C) Sodium (D) Calcium 31. : Which vitamin is essential for oxidative phosphorylation? (A) Vitamin Bβ (Riboflavin) (B) Vitamin K (C) Vitamin A (D) Vitamin D 32. : The hormone glucagon mainly acts on the: (A) Brain (B) Liver (C) Stomach (D) Kidneys 33. : Cholesterol is a precursor of: (A) Fatty acids (B) Bile acids and steroid hormones (C) Proteins (D) Glucose 34. : The enzyme responsible for DNA synthesis is: (A) RNA polymerase (B) DNA polymerase (C) Ligase (D) Helicase 35. : The RQ (Respiratory Quotient) for carbohydrate metabolism is: (A) 0.7 (B) 1.0 (C) 0.8 (D) 0.9 36. : Which vitamin prevents oxidative damage to cells? (A) Vitamin E (B) Vitamin K (C) Vitamin D (D) Vitamin Bβ 37. : The main site of protein synthesis is: (A) Mitochondria (B) Ribosome (C) Nucleus (D) Cytoskeleton 38. : Which amino acid is the precursor of serotonin? (A) Tryptophan (B) Tyrosine (C) Methionine (D) Phenylalanine 39. : Which of the following is a reducing sugar? (A) Sucrose (B) Glucose (C) Cellulose (D) Starch 40. : Fatty acids are transported in the blood as: (A) Free fatty acids bound to albumin (B) Simple lipids (C) Water-soluble proteins (D) Glycerol only 41. : The enzyme responsible for fat digestion in the small intestine is: (A) Lipase (B) Pepsin (C) Trypsin (D) Amylase 42. : Which vitamin deficiency causes megaloblastic anemia? (A) Vitamin C (B) Folic acid (C) Vitamin K (D) Vitamin A 43. : The process by which amino groups are removed from amino acids is called: (A) Deamination (B) Transamination (C) Decarboxylation (D) Oxidation 44. : The enzyme that converts sucrose into glucose and fructose is: (A) Invertase (B) Maltase (C) Amylase (D) Sucrase 45. : The term βessential amino acidsβ refers to those which: (A) Can be synthesized in the body (B) Cannot be synthesized in the body (C) Are stored in the liver (D) Are used in DNA synthesis 46. : Which vitamin is required for blood coagulation? (A) Vitamin D (B) Vitamin K (C) Vitamin E (D) Vitamin Bβ 47. : Gluconeogenesis occurs mainly during: (A) Starvation and fasting (B) High carbohydrate intake (C) Exercise only (D) Sleep 48. : Which compound is the common intermediate in carbohydrate, fat, and protein metabolism? (A) Acetyl-CoA (B) Pyruvate (C) Glycerol (D) Lactic acid 49. : The deficiency of niacin results in: (A) Pellagra (B) Rickets (C) Scurvy (D) Beriberi 50. : The first step in protein digestion occurs in the: (A) Small intestine (B) Stomach (C) Mouth (D) Large intestine