A gas is not produced during

Options

A. Alcoholic fermentation
B. Aerobic respiration
C. Lactic acid fermentation
D. Both A and B

Answer

To determine which process does not produce a gas, we will analyze each of the three options: alcoholic fermentation, aerobic respiration, and lactic acid fermentation.

### Step-by-Step Solution:

1. **Understand the Processes**:
- **Aerobic Respiration**: This process occurs in the presence of oxygen and involves the complete oxidation of glucose. It produces carbon dioxide (CO2) and water (H2O) as by-products, both of which are gases.
- **Alcoholic Fermentation**: This is an anaerobic process (occurs without oxygen) where glucose is converted into ethanol and carbon dioxide. During this process, decarboxylation occurs, releasing CO2 as a gas.
- **Lactic Acid Fermentation**: This process also occurs anaerobically but involves the conversion of glucose into lactic acid. Importantly, it does not involve decarboxylation, meaning no carbon dioxide is released.

2. **Analyze Each Option**:
- **Aerobic Respiration**: Produces CO2 (gas) → **Not the correct answer**.
- **Alcoholic Fermentation**: Produces CO2 (gas) → **Not the correct answer**.
- **Lactic Acid Fermentation**: Produces lactic acid and NAD+ but does not produce any gas → **Correct answer**.

3. **Conclusion**: The process that does not produce a gas is **lactic acid fermentation**.

### Final Answer:
The correct option is **lactic acid fermentation**.

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