What is incorrect about leghaemoglobin?

Options

A. Synthesized by host cell
B. Oxygen scavenger
C. It makes nodules blue coloured.
D. It reduces the enzyme nitrogenase

Answer

**Step-by-Step Solution:**

1. **Understanding Leghaemoglobin**: Leghaemoglobin is a type of hemoglobin found in the root nodules of leguminous plants. It plays a crucial role in nitrogen fixation by maintaining an oxygen concentration that is optimal for the nitrogen-fixing bacteria (Rhizobia) living in symbiosis with the plant.

2. **Characteristics of Leghaemoglobin**:
- It is synthesized by legumes.
- It is found in the root nodules of these plants.
- It is red in color due to the presence of heme groups.
- It helps in transporting oxygen to the nitrogen-fixing bacteria.

3. **Analyzing the Options**: The question asks for the incorrect statement about leghaemoglobin. We need to evaluate each option:
- **Option A**: "Synthesized by the host cell" - This is correct since leghaemoglobin is synthesized by the legume plant cells.
- **Option B**: "Acts as an oxidase scavenger" - This is also correct as leghaemoglobin helps in scavenging excess oxygen.
- **Option C**: "Makes root nodules blue color" - This is incorrect; leghaemoglobin gives root nodules a red or pink color, not blue.
- **Option D**: "Reduces the enzyme nitrogenase" - This is incorrect. Leghaemoglobin protects nitrogenase from oxygen, rather than reducing it.

4. **Conclusion**: The incorrect statements about leghaemoglobin are in options C and D. However, since the question asks for one incorrect statement, the most direct answer is option C, as it misrepresents the color associated with leghaemoglobin.

**Final Answer**: The incorrect statement about leghaemoglobin is that it makes root nodules blue in color.

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