Question

Which of the following reactions causes the conversion of pyruvate into acetyl CoA?

• A. Oxidative decarboxylation
• B. Oxidative dephosphorylation
• C. Oxidative phosphorylation
• D. Oxidative dehydration

Hint:

Remember: pyruvate to acetyl CoA involves loss of CO\textsubscript{2} and oxidation, hence oxidative decarboxylation.

Answer 1

The Correct Option is A

Step 1: Understanding pyruvate conversion.
Pyruvate is converted into acetyl CoA inside the mitochondria by the pyruvate dehydrogenase complex before entering the Krebs cycle.
Step 2: Nature of the reaction.
During this process, one carbon atom is removed as carbon dioxide and pyruvate is oxidized, hence the reaction is called oxidative decarboxylation.
Step 3: Evaluation of options.
(A) Oxidative decarboxylation: Correct — this accurately describes the reaction.
(B) Oxidative dephosphorylation: Incorrect — not related to pyruvate conversion.
(C) Oxidative phosphorylation: Incorrect — it occurs in the electron transport chain.
(D) Oxidative dehydration: Incorrect — no water removal occurs here.
Step 4: Conclusion.
The conversion of pyruvate into acetyl CoA occurs through oxidative decarboxylation.