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: Basic unit of nucleic acids
A) Nucleotide
B) Amino acid
C) Sugar-phosphate
D) Nucleoside
✅ Correct Answer: A
Explanation: A nucleotide consists of a sugar, phosphate, and nitrogenous base and is the building block of DNA and RNA.
Q: Metal ion required for hemoglobin function
A) Copper
B) Magnesium
C) Iron
D) Zinc
✅ Correct Answer: C
Explanation: Iron in the heme group binds oxygen molecules in hemoglobin.
Q: Amino acid with a sulfur-containing side chain
A) Alanine
B) Serine
C) Cysteine
D) Glycine
✅ Correct Answer: C
Explanation: Cysteine contains a thiol group in its side chain, which can form disulfide bonds.
Q: Primary organ for detoxification of drugs
A) Pancreas
B) Liver
C) Spleen
D) Kidney
✅ Correct Answer: B
Explanation: The liver metabolizes and detoxifies harmful substances in the body.
Q: Substrate for the enzyme lactase
A) Sucrose
B) Glucose
C) Lactose
D) Galactose
✅ Correct Answer: C
Explanation: Lactase hydrolyzes lactose into glucose and galactose.