The surface area of mitochondria can be increased by

Options

A. Outer membrane
B. Cristae
C. Matrix
D. All

Answer

To solve the question regarding how the surface area of mitochondria can be increased, we will analyze the structure of mitochondria and identify which components contribute to this increase.

### Step-by-Step Solution:

1. **Understanding Mitochondria Structure**:
- Mitochondria are double-membraned organelles found in eukaryotic cells. They consist of an outer membrane and an inner membrane.

**Hint**: Remember that mitochondria have two membranes, and knowing their functions is key to understanding their structure.

2. **Identifying Membrane Functions**:
- The outer membrane is smooth and does not contribute significantly to the surface area.
- The inner membrane is highly convoluted and forms numerous folds known as cristae.

**Hint**: Focus on the differences between the outer and inner membranes, especially their shapes and structures.

3. **Role of Cristae**:
- The cristae (folds of the inner membrane) significantly increase the surface area available for biochemical reactions, particularly those involved in cellular respiration.

**Hint**: Think about why increased surface area is important for cellular processes like respiration.

4. **Conclusion**:
- Since the inner membrane's cristae increase the surface area of the mitochondria, the correct answer to the question is that the surface area of mitochondria can be increased by the cristae.

**Hint**: Recall that the inner membrane's folds (cristae) are crucial for enhancing the efficiency of respiration.

### Final Answer:
The surface area of mitochondria can be increased by the cristae (the folds of the inner membrane).