Nitrogen fixation is the process of conversion of nitrogen to

Options

A. ammonia
B. nitrite
C. nitrate
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogen Fixation**: Nitrogen fixation is a process that converts atmospheric nitrogen (N₂) into a more usable form for living organisms. The primary product of this conversion is ammonia (NH₃).

2. **Forms of Nitrogen**: Nitrogen in the atmosphere exists as diatomic nitrogen (N₂), which is very stable due to a strong triple bond between the nitrogen atoms. This makes it difficult for most organisms to utilize directly.

3. **Process of Conversion**: The conversion of nitrogen gas to ammonia is crucial because plants cannot use atmospheric nitrogen directly. Instead, they require nitrogen in the form of ammonia or other compounds like nitrites (NO₂⁻) and nitrates (NO₃⁻).

4. **Methods of Nitrogen Fixation**:
- **Biological Nitrogen Fixation**: This is primarily carried out by certain prokaryotic organisms, such as bacteria (e.g., Rhizobium) that live in symbiosis with legumes. These bacteria convert atmospheric nitrogen into ammonia.
- **Non-Biological Nitrogen Fixation**: This occurs through natural phenomena like lightning, which can convert nitrogen into nitrogen oxides (NO, NO₂) or through industrial processes.

5. **Conclusion**: The main outcome of nitrogen fixation is the conversion of nitrogen gas (N₂) into ammonia (NH₃), which can then be utilized by plants to synthesize proteins and other essential compounds.

**Final Answer**: Nitrogen fixation is the process of conversion of nitrogen to ammonia.

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