Roots of which plants contains an oxidising agent?

Options

A. Carrot
B. Soyabean
C. Mustard
D. Radish

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which plant's roots contain an oxidizing agent. This indicates we need to identify a specific plant known for having such a characteristic in its root system.

2. **Identifying the Plant**: The transcript mentions that the soybean plant (Glycine max) is an example of a plant whose roots contain an oxidizing agent.

3. **Family Classification**: Soybean belongs to the family Leguminosae (also known as Fabaceae), which is significant because it indicates a specific group of plants that have symbiotic relationships with certain bacteria.

4. **Role of Rhizobium**: In the root nodules of soybean, there is a symbiotic relationship with a bacterium called Rhizobium. This bacterium is crucial for nitrogen fixation, converting atmospheric nitrogen into forms usable by plants.

5. **Enzyme Involvement**: The enzyme nitrogenase, produced by Rhizobium, is responsible for this nitrogen fixation process. However, it is important to note that nitrogenase is inactive in the presence of oxygen.

6. **Creating Anaerobic Conditions**: To facilitate the activity of nitrogenase, the root nodules contain a pigment called leghemoglobin. This pigment plays a crucial role in trapping oxygen, thus creating anaerobic conditions necessary for nitrogenase to function effectively.

7. **Conclusion**: Since leghemoglobin acts as an oxidizing agent by trapping oxygen and protecting nitrogenase, we conclude that the roots of soybean contain an oxidizing agent.

8. **Final Answer**: The correct answer to the question is soybean (Glycine max).

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