Plants that have mutualistic relations with nitrogen-fixing bacteria provide the bacteria with

Options

A. `N_(2)`
B. enzymes
C. sugars
D. nitrite

Answer

**Step-by-Step Solution:**

1. **Understanding Mutualism**: In mutualistic relationships, both organisms benefit from the association. In this case, we are looking at the relationship between plants (specifically leguminous plants) and nitrogen-fixing bacteria (like Rhizobium).

2. **Role of Nitrogen-Fixing Bacteria**: Nitrogen-fixing bacteria convert atmospheric nitrogen (N₂) into a form that plants can use, such as ammonium (NH₄⁺). This process is essential for plant growth as nitrogen is a critical nutrient for the synthesis of amino acids and proteins.

3. **What Plants Provide**: In this mutualistic relationship, plants provide the bacteria with a carbon source. This is primarily in the form of sugars, which the plants produce through photosynthesis.

4. **What Bacteria Provide**: In return, the bacteria provide the plants with fixed nitrogen (in the form of ammonium), which the plants can use to synthesize proteins and other important molecules.

5. **Conclusion**: Therefore, the correct answer to the question is that plants provide sugars to the nitrogen-fixing bacteria.

**Final Answer**: Plants that have mutualistic relations with nitrogen-fixing bacteria provide the bacteria with sugars.

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