Element involved in nitrogen -fixation is

Options

A. Zinc
B. Boron
C. Iron
D. Chlorine

Answer

To determine the element involved in nitrogen fixation from the options provided (Zinc, Boron, Iron, and Chlorine), we can follow these steps:

### Step-by-Step Solution:

1. **Understand Nitrogen Fixation**: Nitrogen fixation is the process by which atmospheric nitrogen (N₂) is converted into ammonia (NH₃), which can be utilized by plants. This process is crucial for the nitrogen cycle.

2. **Identify the Role of Microorganisms**: Nitrogen fixation can occur biologically through certain microorganisms, particularly prokaryotes. These organisms possess specific enzymes that facilitate the conversion of nitrogen gas into ammonia.

3. **Focus on Nitrogenase Enzyme**: The key enzyme involved in nitrogen fixation is called nitrogenase. This enzyme is responsible for catalyzing the reduction of atmospheric nitrogen to ammonia.

4. **Determine the Composition of Nitrogenase**: Nitrogenase is a complex enzyme that contains metal ions, specifically molybdenum and iron. These metals are essential for the enzyme's activity.

5. **Evaluate the Options**: Among the provided options (Zinc, Boron, Iron, and Chlorine), we need to identify which one is involved in the nitrogen fixation process through the nitrogenase enzyme.

6. **Select the Correct Element**: Since iron is a component of the nitrogenase enzyme and is involved in the nitrogen fixation process, the correct answer is **Iron**.

### Final Answer:
The element involved in nitrogen fixation is **Iron**.

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