NADH is oxidised to `NAD^(+)` rather slowly in fermentation, however the reaction is very vigorous in case of aerobic respiration

Answer

To solve the question regarding the oxidation of NADH to NAD+ in fermentation and aerobic respiration, we can break down the concepts step by step.

### Step-by-Step Solution:

1. **Understanding Respiration Types**:
- Respiration can occur in two main forms: aerobic respiration (in the presence of oxygen) and anaerobic respiration (in the absence of oxygen, commonly referred to as fermentation).

2. **Aerobic Respiration**:
- In aerobic respiration, glucose undergoes complete degradation, resulting in the production of carbon dioxide and water.
- This process is efficient and yields a high amount of energy, specifically a net gain of approximately 38 ATP molecules from one molecule of glucose.
- The oxidation of NADH to NAD+ occurs rapidly because oxygen is readily available to act as the final electron acceptor in the electron transport chain.

3. **Fermentation**:
- In contrast, fermentation involves the partial degradation of glucose, as it occurs without oxygen.
- The energy yield from fermentation is significantly lower, with only a net gain of about 2 ATP molecules per glucose molecule.
- The oxidation of NADH to NAD+ in fermentation happens slowly due to the limited availability of oxygen. This process is essential for regenerating NAD+ so that glycolysis can continue.

4. **Comparative Analysis**:
- The statement in the question claims that NADH is oxidized to NAD+ slowly in fermentation and vigorously in aerobic respiration.
- This is accurate because, in fermentation, the lack of oxygen leads to a slower rate of NADH oxidation, while in aerobic respiration, the presence of oxygen allows for a rapid oxidation process.

5. **Conclusion**:
- Therefore, the statement is true: NADH is oxidized to NAD+ rather slowly in fermentation, whereas the reaction is vigorous in the case of aerobic respiration.

### Final Answer:
The statement is **True**.

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