Enzyme involved in nitrogen assimilation

Options

A. nitrogenase
B. nitrate reductase
C. transferase
D. transaminase

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the enzyme involved in nitrogen assimilation.

2. **Understand Nitrogen Assimilation**: Nitrogen assimilation is the process by which plants convert atmospheric nitrogen into a usable form, primarily ammonia.

3. **Evaluate the Options**: The options given are:
- A) Nitrogenase
- B) Nitrate reductase
- C) Transferase
- D) Transaminase

4. **Analyze Each Option**:
- **Nitrogenase**: This enzyme is crucial for nitrogen fixation, which converts atmospheric nitrogen (N₂) into ammonia (NH₃). It is primarily found in certain bacteria and cyanobacteria (blue-green algae) within specialized cells called heterocysts.
- **Nitrate Reductase**: This enzyme reduces nitrate (NO₃⁻) to nitrite (NO₂⁻) and is involved in the nitrogen cycle but not directly in nitrogen assimilation as it does not convert atmospheric nitrogen.
- **Transferase**: This enzyme transfers functional groups between molecules but does not specifically relate to nitrogen assimilation.
- **Transaminase**: This enzyme catalyzes transamination reactions, which involve the transfer of amino groups but are not directly related to the assimilation of nitrogen from the atmosphere.

5. **Select the Correct Answer**: Based on the analysis, the correct answer is **A) Nitrogenase**, as it is directly involved in the process of nitrogen fixation and thus nitrogen assimilation.

6. **Conclusion**: The enzyme involved in nitrogen assimilation is nitrogenase, which facilitates the conversion of atmospheric nitrogen into ammonia.

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