TCA cycle is named after

Options

A. Embden
B. Emerson
C. Krebs
D. Calvin.

Answer

### Step-by-Step Solution:

1. **Understanding the TCA Cycle**: The TCA cycle, also known as the tricarboxylic acid cycle, is a series of enzyme-catalyzed chemical reactions that occur in aerobic organisms. It plays a crucial role in cellular respiration by helping to release stored energy.

2. **Alternative Names**: The TCA cycle is also referred to as the citric acid cycle. This is important to note as it highlights the cycle's connection to citric acid, which is a key component of the cycle.

3. **Identifying the Namesake**: The TCA cycle is commonly known as the Krebs cycle. This name is derived from the scientist Hans Krebs, who was instrumental in elucidating the cycle's mechanisms.

4. **Eliminating Other Options**: The question provides several names: Emden, Amazon, Krebs, and Calvin. Since we have established that the TCA cycle is named after Hans Krebs, we can eliminate the other names as they do not correspond to the TCA cycle.

5. **Conclusion**: Therefore, the TCA cycle is named after Hans Krebs, making him the correct answer to the question.

### Final Answer:
The TCA cycle is named after **Hans Krebs**.

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