Acetaldehyde is intermediate product in

Options

A. lactic acid fermentation
B. ethyl alcohol fermentation
C. Kreb's cycle
D. glycolysis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the role of acetaldehyde as an intermediate product in various metabolic processes.

2. **Analyzing the Options**:
- **Option A: Lactic Acid Fermentation**: In this process, glucose is converted to pyruvate through glycolysis, and then pyruvate is directly converted to lactate. There is no formation of acetaldehyde in this pathway.
- **Option B: Methyl Alcohol Fermentation**: This option is not commonly discussed in the context of acetaldehyde. Instead, we focus on ethyl alcohol fermentation.
- **Option C: Krebs Cycle**: Acetaldehyde is not an intermediate in the Krebs cycle. The Krebs cycle primarily involves acetyl CoA as the starting molecule.
- **Option D: Glycolysis**: Glycolysis is the pathway that converts glucose to pyruvate, but acetaldehyde is not formed in this process.

3. **Identifying the Correct Pathway**: The key pathway where acetaldehyde is formed is during ethyl alcohol fermentation (also known as alcoholic fermentation). In this anaerobic process:
- Glucose is first converted to pyruvate via glycolysis.
- In the absence of oxygen, pyruvate is converted to acetyl CoA.
- Acetyl CoA is then converted to acetaldehyde.
- Finally, acetaldehyde is converted to ethanol (ethyl alcohol) and carbon dioxide.

4. **Conclusion**: Based on the analysis, acetaldehyde is an intermediate product in **ethyl alcohol fermentation**. Therefore, the correct answer is **Option B**.

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