The number of unit membranes which bound the mitochondria are

Options

A. 1
B. 2
C. 3
D. 4

Answer

To determine the number of unit membranes that bound the mitochondria, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of Mitochondria**: Mitochondria are double-membraned organelles found in eukaryotic cells. This means they have two distinct membranes.

2. **Identify the Membranes**: The two membranes are:
- **Outer Membrane**: This is the membrane that surrounds the mitochondrion and separates it from the cytoplasm.
- **Inner Membrane**: This membrane is located inside the outer membrane and is highly folded into structures known as cristae, which increase the surface area for biochemical reactions.

3. **Count the Membranes**: Since we have identified one outer membrane and one inner membrane, we can conclude that there are a total of two membranes surrounding the mitochondria.

4. **Conclusion**: Therefore, the number of unit membranes that bound the mitochondria is **two**.

### Final Answer:
The number of unit membranes which bound the mitochondria is **two**.

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