Biochemistry · Nutrition and Energy Metabolism

Respiratory quotient (RQ) of 0.7 indicates the body is primarily oxidising:

A Fats ✓
B Carbohydrates
C Mixed diet
D Proteins

Correct answer: A. Fats

Explanation

RQ = CO2 produced / O2 consumed; fat oxidation yields RQ ≈ 0.7 because fatty acids have a low oxygen-to-carbon ratio and require proportionally more O2 for complete oxidation. Carbohydrate oxidation yields RQ = 1.0 (equal CO2 and O2). Mixed diet RQ ≈ 0.85. Protein RQ ≈ 0.8. An RQ >1.0 indicates net lipogenesis from carbohydrates.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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