Which one requires oxygen

Options

A. Fermentation
B. EMP pathway
C. Pentose phosphate pathway
D. None of the above

Answer

To determine which of the given processes requires oxygen, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Fermentation:**
- Fermentation is a metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.
- There are two main types of fermentation: alcoholic fermentation (producing ethanol) and lactic acid fermentation (producing lactic acid).
- **Conclusion:** Fermentation does not require oxygen; it is an anaerobic process.

2. **Analyzing the EMP Pathway (Glycolysis):**
- The EMP pathway, also known as glycolysis, is the process of breaking down glucose into two molecules of pyruvate.
- This pathway occurs in both aerobic (with oxygen) and anaerobic (without oxygen) conditions.
- **Conclusion:** While glycolysis can occur in the presence of oxygen, it does not require oxygen to proceed; hence, it is not exclusively an aerobic process.

3. **Examining the Pentose Phosphate Pathway:**
- The Pentose Phosphate Pathway (PPP) is an alternative metabolic pathway to glycolysis that generates NADPH and pentose sugars.
- This pathway can also function in the absence of oxygen.
- **Conclusion:** The Pentose Phosphate Pathway does not require oxygen; it is an anaerobic process.

4. **Final Evaluation:**
- All three processes (fermentation, EMP pathway, and Pentose Phosphate Pathway) can occur without oxygen.
- Since none of the options require oxygen, the correct answer is that none of the above processes require oxygen.

### Final Answer:
None of the processes listed (fermentation, EMP pathway, Pentose Phosphate pathway) require oxygen.

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