Molybodenum is involved in

Options

A. Photolysis of water
B. Nitrogen fixation, nitrate assimilation
C. Nitrite reduction
D. Nitrification

Answer

**Step-by-Step Solution:**

1. **Understanding Molybdenum's Role**: Molybdenum is a micronutrient essential for plants, required in small amounts. It plays a crucial role in various biochemical processes, particularly in nitrogen metabolism.

2. **Identifying Key Processes**: Molybdenum is involved in:
- Nitrogen fixation
- Nitrate assimilation
- Nitrite reduction
- Nitrification

3. **Enzymatic Functions**:
- Molybdenum is a component of two important enzymes:
- **Nitrogenase**: This enzyme is crucial for nitrogen fixation, which converts atmospheric nitrogen (N₂) into a form that plants can use (ammonia).
- **Nitrate Reductase**: This enzyme is involved in the reduction of nitrates to nitrites and then to ammonia, which is essential for nitrate assimilation.

4. **Eliminating Incorrect Options**:
- **Photolysis of Water**: This process involves the splitting of water molecules using sunlight, primarily facilitated by manganese ions, not molybdenum.
- **Nitrification**: This process is mainly carried out by microorganisms and does not directly involve molybdenum.

5. **Conclusion**: The primary roles of molybdenum are in nitrogen fixation and nitrate assimilation, making it essential for plant growth and development.

**Final Answer**: Molybdenum is involved in nitrogen fixation and nitrate assimilation.

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