Select the incorrect statement.

Options

A. Cytochromes are found in cristae of mitochondria
B. After glycolysis, fate of glucose in mitochondrial matrix is reduction
C. Net gain of ATP in aerobic respiration is 36 ATP
D. There is one step in Kreb's cycle where `FAD^(+)` reduced to `FADH_(2)` .

Answer

To solve the question "Select the incorrect statement," we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Statement 1: Cytochromes are found in the cristae of mitochondria.**
- **Analysis**: Cytochromes are indeed located in the inner mitochondrial membrane, specifically within the cristae. They play a crucial role in the electron transport chain (ETC) during aerobic respiration.
- **Conclusion**: This statement is **correct**.

2. **Statement 2: After glycolysis, the fate of glucose in the mitochondrial matrix is reduction.**
- **Analysis**: After glycolysis, glucose does not undergo reduction in the mitochondrial matrix. Instead, it is oxidized during the Krebs cycle (also known as the citric acid cycle). The products of this oxidation are carbon dioxide, water, and ATP. Therefore, saying that the fate of glucose is reduction is incorrect.
- **Conclusion**: This statement is **incorrect**.

3. **Statement 3: Net gain of ATP in aerobic respiration is 36 ATP.**
- **Analysis**: In aerobic respiration, the complete oxidation of one molecule of glucose can yield a net gain of approximately 36 ATP molecules (though this number can vary slightly depending on the cell type and conditions).
- **Conclusion**: This statement is **correct**.

4. **Statement 4: There is one step in the Krebs cycle where FAD is reduced to FADH2.**
- **Analysis**: This statement is accurate. In the Krebs cycle, there is indeed a step where FAD is reduced to FADH2, which then contributes to the electron transport chain.
- **Conclusion**: This statement is **correct**.

### Final Conclusion:
The **incorrect statement** among the options provided is **Statement 2**: "After glycolysis, the fate of glucose in the mitochondrial matrix is reduction."