Mycorrhizae enhance plant nutrition mainly by

Options

A. absorbing water and minerals through the fungal hyphae.
B. providing sugar to root cells, which have no chloroplasts.
C. converting atmospheric nitrogen to ammonia.
D. enabling the roots to parasitize neighboring plants.

Answer

**Step-by-Step Solution:**

1. **Understanding Mycorrhizae**: Mycorrhizae are symbiotic associations between fungi and the roots of green plants. This relationship is beneficial for both organisms.

2. **Function of Mycorrhizae**: In this symbiotic relationship, the plant provides organic molecules (like sugars) produced through photosynthesis to the fungus. In return, the fungus aids the plant by enhancing its nutrient uptake.

3. **Mechanism of Nutrient Uptake**: The fungus absorbs water and minerals from the soil through its structures called fungal hyphae. These hyphae are long, branching, and filamentous, forming a dense network around the plant's roots or even penetrating root cells.

4. **Evaluating the Options**:
- **Option 1**: "Helps absorbing water and minerals through the fungal hyphae." - This is correct as it describes the primary role of mycorrhizae in enhancing plant nutrition.
- **Option 2**: "Providing sugar to root cells which have no chloroplasts." - This is incorrect because the plant itself produces sugars.
- **Option 3**: "Converting atmospheric nitrogen to ammonia." - This is incorrect as nitrogen fixation is performed by specific bacteria, not mycorrhizae.
- **Option 4**: "Enabling the roots to parasitize neighboring plants." - This is incorrect because mycorrhizae do not parasitize other plants.

5. **Conclusion**: The correct answer is that mycorrhizae enhance plant nutrition mainly by helping absorb water and minerals through the fungal hyphae.

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