Ethanol is formed from acetaldehyde by an enzyme called

Options

A. Lactate dehyderogenase
B. Pyruvate kinase
C. Alcohol dehydrogenase
D. Pyruvate decarboxylase.

Answer

To answer the question "Ethanol is formed from acetaldehyde by an enzyme called," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Process**: Recognize that the formation of ethanol from acetaldehyde is part of alcoholic fermentation. This process occurs in the absence of oxygen, making it a type of anaerobic respiration.

2. **Identify the Reaction**: In alcoholic fermentation, acetaldehyde is an intermediate product. Ethanol is produced from acetaldehyde through a specific enzymatic reaction.

3. **Know the Enzyme Involved**: The enzyme responsible for the conversion of acetaldehyde to ethanol is a type of dehydrogenase. Specifically, it is known as alcohol dehydrogenase.

4. **Conclude the Answer**: Therefore, the enzyme that catalyzes the reaction converting acetaldehyde to ethanol is called alcohol dehydrogenase.

### Final Answer:
Ethanol is formed from acetaldehyde by an enzyme called **alcohol dehydrogenase**.

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