Which of the following compounds produced by the human liver during prolonged fasting is classified as a true ketone body?
- A Acetyl-CoA
- B HMG-CoA
- C Beta-hydroxybutyrate ✓
- D Malonyl-CoA
Correct answer: C. Beta-hydroxybutyrate
Explanation
The three ketone bodies are acetoacetate, beta-hydroxybutyrate, and acetone. Acetoacetate is formed first from HMG-CoA by HMG-CoA lyase; beta-hydroxybutyrate arises by NADH-dependent reduction of acetoacetate, and acetone forms by spontaneous decarboxylation. Acetyl-CoA is the precursor, while mitochondrial HMG-CoA is an intermediate of ketogenesis and malonyl-CoA belongs to fatty acid synthesis. Only the three named products are exported and used as fuels.
Reference: Lippincott's Illustrated Reviews: Biochemistry, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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