The inner membrane of mitochondria bears folding/finger like projections, these-

Options

A. incerase surface area
B. increase thickness of mitochondria
C. keep all the substances away
D. increase protein oxidation

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of Mitochondria**: Mitochondria are known as the powerhouse of the cell and have a unique structure consisting of two membranes: an outer membrane and an inner membrane.

2. **Identifying the Inner Membrane**: The inner membrane of mitochondria is highly convoluted, meaning it has many folds. These folds increase the surface area available for biochemical reactions.

3. **Recognizing the Projections**: The finger-like projections formed by the folding of the inner membrane are called cristae. These cristae extend into the mitochondrial matrix and are crucial for the functioning of the mitochondria.

4. **Function of Cristae**: The increased surface area provided by the cristae allows for more space for the proteins and enzymes involved in the electron transport chain and ATP synthesis. This is essential for the production of ATP, the energy currency of the cell.

5. **Evaluating the Options**: The question presents several options regarding the purpose of these projections:
- Increased surface area
- Increased thickness of mitochondria
- Keeping all substances away
- Increased protein oxidation

6. **Selecting the Correct Answer**: The correct answer is "increased surface area" because the cristae enhance the capacity for ATP production by providing more space for the necessary biochemical processes.

7. **Conclusion**: Therefore, the inner membrane of mitochondria bears folding/finger-like projections known as cristae, which serve to increase the surface area for ATP production.

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