In which part of the leguminous plants does Rhizobium live?

Options

A. Flowers
B. Leaves
C. Stems
D. Roots

Answer

**Step-by-Step Solution:**

1. **Understanding Rhizobium**: Rhizobium is a type of bacteria known for its ability to fix nitrogen. It is classified as a symbiotic nitrogen-fixing bacteria, which means it forms a mutual relationship with certain plants.

2. **Identifying Leguminous Plants**: Leguminous plants are a group of plants that belong to the family Fabaceae. Common examples include beans, peas, and lentils. These plants have a special relationship with Rhizobium.

3. **Location of Rhizobium**: Rhizobium bacteria primarily live in the roots of leguminous plants. They establish a symbiotic relationship with the plant roots, allowing them to fix atmospheric nitrogen into a form that the plant can use.

4. **Mechanism of Nitrogen Fixation**: The process begins when Rhizobium bacteria in the soil come into contact with the root hairs of leguminous plants. They enter the roots and start fixing nitrogen, converting atmospheric nitrogen into ammonia, which is a usable form for the plant.

5. **Conclusion**: Therefore, the correct answer to the question is that Rhizobium lives in the roots of leguminous plants.

**Final Answer**: Rhizobium lives in the roots of leguminous plants.

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