In Mitochondria, Cristae act as sites for

Options

A. Protein synthesis
B. Phosphorylation of flavoproteins
C. Breakdown of macromolecules
D. Oxodataion- reduction reaction

Answer

### Step-by-Step Solution:

1. **Understanding Mitochondria**: Mitochondria are known as the powerhouse of the cell because they are responsible for producing ATP (adenosine triphosphate), which is the energy currency of the cell.

2. **Role of Cristae**: The inner membrane of the mitochondria is folded into structures called cristae. These cristae increase the surface area available for biochemical reactions.

3. **Biochemical Reactions in Mitochondria**: The main processes that occur in the mitochondria include the Krebs cycle (also known as the citric acid cycle) and oxidative phosphorylation. Both of these processes involve a series of oxidation-reduction (redox) reactions.

4. **Evaluating Options**:
- **Protein Synthesis**: This process occurs primarily in ribosomes, not in mitochondria. Therefore, this option is incorrect.
- **Phosphorylation of Flavoproteins**: While flavoproteins are involved in the electron transport chain, this option does not specifically describe the primary function of cristae.
- **Breakdown of Macromolecules**: This process is generally associated with lysosomes and digestive enzymes, not specifically with cristae.
- **Oxidation-Reduction Reactions**: This is the correct answer, as cristae are indeed the sites where oxidation-reduction reactions take place during ATP production.

5. **Conclusion**: Therefore, in mitochondria, cristae act as sites for oxidation-reduction reactions.

### Final Answer:
In mitochondria, cristae act as sites for oxidation-reduction reactions.

---