Which of the following statements is incorrect in relation to leghaemoglobin ?

Options

A. Leghaemoglobin functions as oxygen scavenger .
B. It is synthesized by host cell.
C. It makes nodules pink coloured .
D. It oxidizes enzyme nitrogenase .

Answer

To determine which statement about leghaemoglobin is incorrect, we can analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Leghaemoglobin**:
- Leghaemoglobin is a protein found in the root nodules of leguminous plants. It is similar to hemoglobin in animals and serves a specific function in the plant.

2. **Analyzing the Statements**:
- **Statement 1**: "Leghaemoglobin functions as the oxygen scavenger."
- This statement is **correct**. Leghaemoglobin binds to oxygen and helps maintain a low concentration of oxygen in the root nodules, protecting the nitrogenase enzyme from being inactivated by oxygen.

- **Statement 2**: "Leghaemoglobin is synthesized by the host cell."
- This statement is also **correct**. The leghaemoglobin is produced by the plant (host) cells in response to the presence of nitrogen-fixing bacteria in the root nodules.

- **Statement 3**: "It makes nodules pink in color."
- This statement is **correct** as well. Leghaemoglobin gives the root nodules a characteristic pink color due to its heme group.

- **Statement 4**: "It oxidizes the enzyme nitrogenase."
- This statement is **incorrect**. Leghaemoglobin does not oxidize nitrogenase; rather, it protects nitrogenase from oxygen, allowing it to function properly in nitrogen fixation.

3. **Conclusion**:
- The incorrect statement regarding leghaemoglobin is **Statement 4**: "It oxidizes the enzyme nitrogenase."

### Final Answer:
The incorrect statement in relation to leghaemoglobin is: **"It oxidizes the enzyme nitrogenase."**

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