Nitrogenase in an enzyme used in :

Options

A. Respiration
B. Nitrogen oxidation
C. Nitrogen reduction
D. Both (B) and (C )

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogenase**: Nitrogenase is an enzyme that plays a crucial role in the nitrogen cycle. It is primarily responsible for the process of nitrogen fixation, which converts atmospheric nitrogen (N2) into ammonia (NH3).

2. **Location of Nitrogenase**: This enzyme is found in prokaryotic organisms, specifically within their plasmids. Plasmids are small, circular DNA molecules that are separate from chromosomal DNA and can carry genes that provide advantages, such as nitrogen fixation.

3. **Function of Nitrogenase**: The main function of nitrogenase is to catalyze the reduction of atmospheric nitrogen (N2) to ammonia (NH3). This process is vital for making nitrogen available to living organisms, as most cannot utilize atmospheric nitrogen directly.

4. **Process Involved**: The process that nitrogenase facilitates is known as nitrogen reduction. During this process, nitrogen (N2) is reduced to ammonia (NH3), which can then be used by plants and other organisms to synthesize essential compounds.

5. **Conclusion**: Based on the function of nitrogenase, we can conclude that it is involved in nitrogen reduction, making the correct answer to the question: Nitrogenase is an enzyme used in nitrogen reduction.

**Final Answer**: Nitrogenase is an enzyme used in nitrogen reduction.

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