Pyruvic acid is the end product of

Options

A. Krebs cycle
B. Electron transport system
C. Photosynthesis
D. Glycolysis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the process in which pyruvic acid is the end product.

2. **Analyzing the Options**:
- **Krebs Cycle**: This cycle is also known as the tricarboxylic acid cycle (TCA cycle). It involves the conversion of acetyl-CoA into carbon dioxide and energy carriers (NADH, FADH2) but does not produce pyruvic acid as an end product.
- **Electron Transport System**: This process involves the transfer of electrons through a series of complexes to generate ATP. It does not produce pyruvic acid.
- **Photosynthesis**: This process occurs in chloroplasts and involves the conversion of light energy into chemical energy, producing glucose and oxygen. Pyruvic acid is not a product of photosynthesis.
- **Glycolysis**: This is the metabolic pathway that breaks down glucose into pyruvic acid. It occurs in the cytoplasm and is the only process among the options that results in pyruvic acid as an end product.

3. **Conclusion**: Based on the analysis, the correct answer is glycolysis, as it is the process that directly produces pyruvic acid from glucose.

4. **Final Answer**: Pyruvic acid is the end product of glycolysis.

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