Activity of nitrogenase in nitrogen fixing micro-organisms can be seen when

Options

A. Methane is converted to ethane
B. Ethane is converted to methane
C. Ethylene is converted to acetylene
D. Acetylene is converted or reduced to ethylene

Explanation

**Step-by-Step Solution:**

1. **Understanding Nitrogenase Activity**: Nitrogenase is an enzyme responsible for the process of nitrogen fixation, which converts atmospheric nitrogen (N2) into ammonia (NH3). This process is crucial for making nitrogen available to plants.

2. **Oxygen Sensitivity**: Nitrogenase is highly sensitive to oxygen. The presence of oxygen can inhibit its activity, making it essential for nitrogen fixation to occur in anaerobic (oxygen-free) conditions.

3. **Measuring Nitrogenase Activity**: To measure the activity of nitrogenase in nitrogen-fixing microorganisms, a specific method called the Acetylene Reduction Assay is used. This method exploits the enzyme's ability to reduce acetylene (C2H2) to ethylene (C2H4).

4. **Chemical Reaction**: In this assay, acetylene is introduced to the environment where nitrogen-fixing microorganisms are present. The nitrogenase enzyme reduces acetylene, breaking its triple bond and converting it into ethylene.

5. **Conclusion**: Therefore, the activity of nitrogenase in nitrogen-fixing microorganisms can be observed when acetylene is converted or reduced to ethylene.

**Final Answer**: The activity of nitrogenase in nitrogen-fixing microorganisms can be seen when acetylene is converted or reduced to ethylene.

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