During complete oxidation of macronutrients, metabolic water is produced. Which substrate yields the HIGHEST amount of metabolic water per gram oxidized?
- A Carbohydrate
- B Protein
- C Fat ✓
- D Nucleic acid
Correct answer: C. Fat
Explanation
Fat oxidation produces approximately 1.07 mL of water per gram, the highest among macronutrients. Carbohydrate yields about 0.6 mL/g and protein about 0.4 mL/g. This is why desert animals like the kangaroo rat rely heavily on metabolic water from fat oxidation. The higher hydrogen content of fat accounts for greater water yield per gram.
Reference: Ganong's Review of Medical Physiology, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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