Mitochondria are rich in

Options

A. iron
B. cobalt
C. molybdenum
D. manganese

Explanation

**Step-by-Step Solution:**

1. **Understanding Mitochondria**: Mitochondria are known as the "powerhouse of the cell" because they are responsible for producing energy in the form of adenosine triphosphate (ATP).

2. **Identifying the Elements**: The question provides four options: iron, cobalt, molybdenum, and manganese. We need to determine which of these elements is abundant in mitochondria.

3. **Analyzing Each Option**:
- **Iron**: While iron is essential for hemoglobin formation in red blood cells, it is not specifically known for its role in mitochondria.
- **Cobalt**: Cobalt is primarily associated with vitamin B12 and is not a significant component of mitochondria.
- **Molybdenum**: Molybdenum plays a role in nitrogen fixation and is not known to be abundant in mitochondria.
- **Manganese**: Manganese is involved in various enzymatic processes, including those in the mitochondria. It plays a crucial role in the electron transport chain, which is essential for ATP production.

4. **Conclusion**: Based on the analysis, the element that is rich in mitochondria is **manganese**.

**Final Answer**: Mitochondria are rich in manganese.

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