The first member of the TCA cycle is

Options

A. Acetyl CoA
B. Citric acid
C. OAA
D. Pyruvic acid

Explanation

**Step-by-Step Solution:**

1. **Understanding the TCA Cycle**: The TCA cycle, also known as the Krebs cycle or citric acid cycle, is a crucial metabolic pathway that plays a key role in cellular respiration. It occurs in the mitochondria of cells.

2. **Identifying the First Member**: The first member of the TCA cycle is Acetyl-CoA. This molecule is derived from carbohydrates, fats, and proteins and enters the cycle to begin the process of energy production.

3. **Formation of Citrate**: Once Acetyl-CoA enters the TCA cycle, it combines with oxaloacetate (another molecule present in the cycle) to form citrate (citric acid), which is the first compound in the cycle.

4. **Conclusion**: Therefore, the first member of the TCA cycle is Acetyl-CoA, which is then converted into citrate.

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