Cristae occur in

Options

A. Golgi body
B. Nucleus
C. Mitochondria
D. E.R.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where cristae occur. Cristae are structures found in certain cell organelles.

2. **Evaluating the Options**: The options provided are:
- Option 1: Golgi body
- Option 2: Nucleus
- Option 3: Mitochondria
- Option 4: Endoplasmic reticulum (ER)

3. **Analyzing Each Option**:
- **Option 1: Golgi body**: The Golgi body consists of flattened, stacked pouches called cisternae. It does not contain cristae. Therefore, this option is incorrect.

- **Option 2: Nucleus**: The nucleus contains chromatin (DNA and protein) and a gel-like substance called nucleoplasm. It does not have cristae. This option is also incorrect.

- **Option 3: Mitochondria**: Mitochondria are known as the powerhouse of the cell and have a double membrane structure. The inner membrane has folds called cristae, which increase the surface area for energy production. This is the correct option.

- **Option 4: Endoplasmic reticulum (ER)**: The ER consists of rough (RER) and smooth (SER) types, made up of interconnected membranes and tubular structures. It does not contain cristae. Thus, this option is incorrect.

4. **Conclusion**: Based on the analysis, cristae occur in mitochondria. Therefore, the correct answer is **Option 3: Mitochondria**.

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