Which of the following process is used in the conversion of pyruvate to acetyl CoA ?

Options

A. oxidative decarboxylation
B. Oxidative decarboxylation
C. Oxidative dehydration
D. Oxidative phosphorylation.

Answer

To solve the question regarding the conversion of pyruvate to acetyl CoA, we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Pyruvate**:
- Pyruvate is a 3-carbon compound produced from glycolysis. Before entering the Krebs cycle, it must be converted to acetyl CoA.

2. **Decarboxylation Process**:
- The conversion of pyruvate to acetyl CoA involves the removal of one carbon atom in the form of carbon dioxide (CO2). This process is known as decarboxylation.

3. **Formation of NADH**:
- During this reaction, NAD+ is reduced to NADH. This means that NAD+ accepts electrons and a proton (H+), which is a key step in the process as it captures energy.

4. **Addition of Coenzyme A**:
- Coenzyme A (CoA) is then added to the remaining 2-carbon molecule (acetyl group), resulting in the formation of acetyl CoA.

5. **Overall Reaction**:
- The overall reaction can be summarized as:
- Pyruvate + CoA + NAD+ → Acetyl CoA + CO2 + NADH

6. **Identifying the Process**:
- The entire process is classified as oxidative decarboxylation because it involves both the oxidation of NAD+ to NADH and the decarboxylation (removal of CO2).

### Conclusion:
The correct answer to the question is that the process used in the conversion of pyruvate to acetyl CoA is **oxidative decarboxylation**.

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