Oxidation of pyruvate to `CO_(2)" and "H_(2)O` occurs through

Options

A. Citric acid cycle
B. Tricarboxylic acid
C. Krebs cycle
D. All the above

Answer

To answer the question regarding the oxidation of pyruvate to carbon dioxide (CO₂) and water (H₂O), we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Pyruvate Formation**:
- Pyruvate is produced from glucose during the process of glycolysis. Glycolysis is the first step in cellular respiration, where glucose is broken down into two molecules of pyruvate.

2. **Fate of Pyruvate**:
- After glycolysis, the pyruvate molecules can enter the mitochondria where they undergo further processing. The fate of pyruvate is crucial for aerobic respiration.

3. **Conversion to Acetyl-CoA**:
- Before entering the Krebs cycle, pyruvate is converted into acetyl-CoA. This conversion is catalyzed by the enzyme pyruvate dehydrogenase and releases one molecule of CO₂ as a byproduct.

4. **Entering the Krebs Cycle**:
- Acetyl-CoA then enters the Krebs cycle (also known as the citric acid cycle or tricarboxylic acid cycle). This cycle is a series of chemical reactions used by all aerobic organisms to generate energy.

5. **Oxidation Process**:
- During the Krebs cycle, acetyl-CoA is oxidized, leading to the production of CO₂ and H₂O. The cycle produces electron carriers (NADH and FADH₂) that are used in the electron transport chain to generate ATP.

6. **Conclusion**:
- Therefore, the oxidation of pyruvate to CO₂ and H₂O occurs through the Krebs cycle (or citric acid cycle), which is also referred to as the tricarboxylic acid cycle. Since all these terms refer to the same metabolic pathway, the correct answer to the question is "all of the above".

### Final Answer:
The oxidation of pyruvate to CO₂ and H₂O occurs through **all of the above**: citric acid cycle, tricarboxylic acid cycle, and Krebs cycle.

---