Complete oxidation of palmitate (C16:0) requires repeated cycles of beta-oxidation. What is the total NADPH cost of synthesizing one molecule of palmitate de novo from acetyl-CoA?
- A 7 NADPH
- B 8 NADPH
- C 14 NADPH ✓
- D 16 NADPH
Correct answer: C. 14 NADPH
Explanation
Palmitate synthesis requires 7 elongation cycles after the initial priming condensation. Each cycle uses 2 NADPH for the beta-ketoacyl reduction and enoyl reduction steps, giving 7 x 2 = 14 NADPH. Seven ATP are also consumed by acetyl-CoA carboxylase to make the seven malonyl-CoA molecules. Options A and B confuse the cycle count with the reductive cofactor stoichiometry.
Reference: Lehninger Principles of Biochemistry, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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