Biochemistry MCQs
Biochemistry MCQs cover enzymes, metabolism, vitamins, nucleic acids, and clinical correlations. Perfect for MDCAT, USMLE, FCPS, and competitive exams, these quizzes strengthen molecular biology concepts and link biochemical processes to human health and disease.
Q: Base pairing in DNA follows
A) A–A and G–G
B) A–C and G–T
C) A–T and G–C
D) T–T and C–C
✅ Correct Answer: C
Explanation: DNA strands are held together by A–T and G–C pairings.
Q: The enzyme lipase acts on
A) Protein
B) Lipid
C) DNA
D) Starch
✅ Correct Answer: B
Explanation: Lipase catalyzes the breakdown of lipids into fatty acids and glycerol.
Q: RNA synthesis is catalyzed by
A) RNA polymerase
B) Protease
C) Helicase
D) DNA ligase
✅ Correct Answer: A
Explanation: RNA polymerase reads DNA and synthesizes RNA.
Q: Vitamins required in trace amounts function as
A) Coenzymes
B) Antibodies
C) Hormones
D) Enzymes
✅ Correct Answer: A
Explanation: Many vitamins serve as essential coenzymes in metabolic pathways.
Q: Hydrogen bonding is important in
A) DNA base pairing
B) Primary structure
C) Ionic bonding
D) Peptide bond formation
✅ Correct Answer: A
Explanation: Hydrogen bonds stabilize base pairs in the DNA double helix.