Cristae are found in :-

Options

A. Surface of grana
B. Surface of plasma membrane.
C. Membrane of Mitochondria
D. Nuclear Membrane.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where cristae are found. Cristae are structures associated with a specific organelle in the cell.

2. **Identifying the Organelles**: The options provided are:
- Surface of grana
- Surface of plasma membrane
- Membrane of mitochondria
- Nuclear membrane

3. **Analyzing Each Option**:
- **Surface of Grana**: Grana are stacks of thylakoids found in chloroplasts, which are involved in photosynthesis. Cristae are not found here.
- **Surface of Plasma Membrane**: The plasma membrane surrounds the cell and does not contain cristae.
- **Membrane of Mitochondria**: Mitochondria are known as the powerhouse of the cell and have a double membrane structure. The inner membrane is folded into structures called cristae.
- **Nuclear Membrane**: The nuclear membrane surrounds the nucleus and does not contain cristae.

4. **Conclusion**: Based on the analysis, cristae are specifically found in the membrane of mitochondria. The folds in the inner membrane increase the surface area for biochemical reactions, particularly aerobic respiration.

5. **Final Answer**: Cristae are found in the membrane of mitochondria.

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