______conditions are created by lagnaemoglobin in the root nodule of a legume.

Options

A. Aerobic
B. Anaerobic
C. acidic
D. alkaline

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of Leghemoglobin:**
- Leghemoglobin is a protein found in the root nodules of leguminous plants. It is similar to hemoglobin in animals and is crucial for the plant's nitrogen-fixing ability.

2. **Identifying the Conditions:**
- The question asks about the conditions created by leghemoglobin in the root nodules. The two primary conditions to consider are aerobic (high oxygen) and anaerobic (low oxygen).

3. **Aerobic Conditions:**
- In aerobic conditions, the oxygen levels are high. High levels of oxygen can interfere with the function of the nitrogen-fixing enzyme called nitrogenase. If nitrogenase is inhibited, the root nodules cannot fix atmospheric nitrogen, which is essential for the plant's growth.

4. **Anaerobic Conditions:**
- In contrast, anaerobic conditions have low oxygen levels. Leghemoglobin helps maintain low oxygen levels in the root nodules, which is favorable for the activity of nitrogenase. This allows the root nodules to effectively fix nitrogen.

5. **Conclusion:**
- Therefore, leghemoglobin creates anaerobic conditions in the root nodules of legumes, which are essential for nitrogen fixation. The correct answer to the question is that anaerobic conditions are created by leghemoglobin.

**Final Answer:**
Anaerobic conditions are created by leghemoglobin in the root nodule of a legume.

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