Pyruvic acid is the end product of which process ?

Options

A. Krebs cycle
B. Calvin cycle
C. Pentose phosphate pathwaqy
D. Glycolysis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the process that produces pyruvic acid as its end product.

2. **Evaluating Options**:
- **Option A: Krebs Cycle**: The Krebs cycle, also known as the citric acid cycle, primarily produces carbon dioxide and water, not pyruvic acid. Therefore, this option is incorrect.
- **Option B: Calvin Cycle**: The Calvin cycle is involved in photosynthesis and produces glyceraldehyde 3-phosphate as its end product. Thus, this option is also incorrect.
- **Option C: Pentose Phosphate Pathway**: This pathway produces ribose 5-phosphate and NADPH. Therefore, this option is incorrect as well.
- **Option D: Glycolysis**: Glycolysis is the process that breaks down glucose into pyruvic acid. This is the correct option since pyruvic acid is indeed the end product of glycolysis.

3. **Conclusion**: The correct answer is D: Glycolysis.

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