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: Element found in the structure of heme
A) Magnesium
B) Iron
C) Copper
D) Zinc
✅ Correct Answer: B
Explanation: Iron is the central atom in the heme group and binds oxygen.
Q: Molecule acting as the main electron carrier in respiration
A) ATP
B) Glucose
C) NAD+
D) FADH2
✅ Correct Answer: C
Explanation: NAD+ accepts electrons during metabolic reactions and becomes NADH.
Q: Lipid component contributing to membrane fluidity
A) Triglycerides
B) Cholesterol
C) Phospholipids
D) Glycolipids
✅ Correct Answer: B
Explanation: Cholesterol intercalates between phospholipids, maintaining fluidity and stability.
Q: Level of protein structure formed by alpha helices and beta sheets
A) Secondary
B) Quaternary
C) Tertiary
D) Primary
✅ Correct Answer: A
Explanation: Secondary structure includes alpha helices and beta-pleated sheets.
Q: Function of ribosomal RNA
A) Catalysis of peptide bond formation
B) Gene regulation
C) Lipid synthesis
D) Energy storage
✅ Correct Answer: A
Explanation: rRNA acts as a ribozyme catalyzing peptide bond formation during translation.