In which part of mitochondria does ATP synthesis occur?

Options

A. `F_(1)`
B. `F_(0)`
C. Cristae
D. Inner membrane of mitochondria

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the specific part of the mitochondria where ATP synthesis occurs.

2. **Identifying the Options**: We have several options to consider:
- Option 1: F1 subunit
- Option 2: F0 subunit
- Option 3: Crystae
- Option 4: Inner membrane of mitochondria

3. **Analyzing Option 1 (F1 subunit)**: The F1 subunit is part of ATP synthase, which is responsible for catalyzing the synthesis of ATP. This is the correct answer because ATP synthesis occurs here.

4. **Analyzing Option 2 (F0 subunit)**: The F0 subunit is a proton pore embedded in the mitochondrial membrane. It plays a role in the process of ATP synthesis but does not directly synthesize ATP itself. Therefore, this option is incorrect.

5. **Analyzing Option 3 (Crystae)**: Crystae are the infoldings of the inner mitochondrial membrane. While they increase the surface area for reactions to occur, they are not the site of ATP synthesis. Thus, this option is also incorrect.

6. **Analyzing Option 4 (Inner membrane of mitochondria)**: The inner membrane is where the electron transport chain occurs, but ATP synthesis specifically takes place at the F1 subunit of ATP synthase. Therefore, this option is incorrect as well.

7. **Conclusion**: Based on the analysis, the correct answer is Option 1: F1 subunit, as this is where ATP synthesis occurs in the mitochondria.

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