Mechansim of aerboic respiraton//tricarboxylic acid pathway was disocovered by

Options

A. Calvin
B. Krebs
C. Pasteur
D. Hatch and Slack.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the discovery of the mechanism of aerobic respiration, specifically the tricarboxylic acid (TCA) pathway.

2. **Identifying the Key Terms**:
- Aerobic respiration: A process that requires oxygen to break down substrates (like glucose) to produce energy.
- Tricarboxylic acid pathway: Also known as the Krebs cycle, it is a series of chemical reactions used by all aerobic organisms to generate energy.

3. **Analyzing the Options**: The options provided are:
- Kelvin
- Krebs
- Pasteur
- Hatch and Slack

4. **Evaluating Each Option**:
- **Kelvin**: Known for the Kelvin cycle, which is related to photosynthesis, not respiration.
- **Krebs**: Sir Hans Adolf Krebs is credited with discovering the TCA cycle, which is integral to aerobic respiration.
- **Pasteur**: Famous for his work in microbiology and principles of vaccination, not specifically for the TCA cycle.
- **Hatch and Slack**: Known for the Hatch-Slack pathway, which is related to photosynthesis in certain plants.

5. **Conclusion**: Based on the evaluation, the correct answer is **Krebs**, as he discovered the mechanism of aerobic respiration, which is also referred to as the Krebs cycle.

### Final Answer:
The mechanism of aerobic respiration, specifically the tricarboxylic acid pathway, was discovered by **Krebs**.

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