Leguminous plants such as pea, groundnut and beans play a special role in the process of ______.

Options

A. nitrogen fixation
B. ammonification
C. denitrification
D. assimilation

Answer

**Step-by-Step Solution:**

1. **Identify the Role of Leguminous Plants:**
Leguminous plants such as pea, groundnut, and beans are known for their unique ability to interact with certain bacteria in the soil.

2. **Understand the Symbiotic Relationship:**
These plants form a symbiotic relationship with rhizobium bacteria, which reside in nodules on their roots. This relationship is beneficial for both the plants and the bacteria.

3. **Define Nitrogen Fixation:**
The primary role of these leguminous plants is in the process of nitrogen fixation. Nitrogen fixation is the conversion of atmospheric nitrogen (which is abundant but not usable by plants) into a form that plants can absorb and utilize, such as ammonia.

4. **Explain the Importance of Nitrogen:**
Nitrogen is an essential nutrient for plants, as it is a key component of amino acids, proteins, and nucleic acids. However, plants cannot directly use atmospheric nitrogen.

5. **Conclude with the Correct Answer:**
Therefore, leguminous plants like pea, groundnut, and beans play a special role in the process of nitrogen fixation.

**Final Answer:**
Leguminous plants such as pea, groundnut, and beans play a special role in the process of **nitrogen fixation**.

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