In aerobic respiration, first `CO_(2)` is liberated during

Options

A. Oxidation of pyruvate
B. Decarboxylation of oxalosuccinate
C. Decarboxylation of `alpha`-ketoglutarate
D. `Alcoholic fermentation

Answer

### Step-by-Step Solution:

1. **Understanding Aerobic Respiration**: Aerobic respiration is a metabolic process that requires oxygen to convert glucose into energy. It involves several stages, including glycolysis, the Krebs cycle, and oxidative phosphorylation.

2. **Identifying the Process**: The question asks when carbon dioxide (CO₂) is first liberated during aerobic respiration. The key stages to consider are glycolysis, the conversion of pyruvate, and the Krebs cycle.

3. **Glycolysis**: In glycolysis, glucose is broken down into two molecules of pyruvate. This process occurs in the cytoplasm and does not release CO₂.

4. **Conversion of Pyruvate**: After glycolysis, pyruvate enters the mitochondria. Here, it undergoes a process called oxidative decarboxylation, where each pyruvate molecule is converted into acetyl-CoA.

5. **Decarboxylation**: During this conversion, one carbon atom is removed from the pyruvate molecule, which is released as CO₂. This is the first instance of CO₂ being liberated in aerobic respiration.

6. **Conclusion**: Therefore, the first CO₂ is liberated during the oxidation of pyruvate, which is the correct answer.

### Final Answer:
In aerobic respiration, the first CO₂ is liberated during the oxidation of pyruvate.

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