Mycorrhiza is

Options

A. symbiotic association of a soil fungus and roots of higher plants
B. parasite association between a fungus and roots of seeded plants
C. saprophytic association between a fungus and roots of seeded plants
D. symbiotic assocation between an algae and fungi

Answer

**Step-by-Step Solution:**

1. **Definition of Mycorrhiza**: Mycorrhiza refers to the symbiotic association between soil fungi and the roots of higher plants. This relationship is crucial for both organisms involved.

2. **Nature of the Relationship**: In this symbiotic relationship, the fungi enhance the root surface area of the plants. This increased surface area allows the plants to absorb more nutrients and minerals from the soil, which are essential for their growth.

3. **Benefits to Fungi**: In return, the higher plants provide carbohydrates to the fungi. These carbohydrates are vital for the growth and survival of the fungi, as they are a primary energy source.

4. **Mutual Benefit**: The relationship is mutually beneficial; neither the fungi nor the plants harm each other. Instead, both parties gain advantages from this association, leading to improved growth and health for both.

5. **Conclusion**: Therefore, mycorrhiza can be defined as a symbiotic association of soil fungi and the roots of higher plants, where both organisms benefit from the relationship.

**Final Answer**: Mycorrhiza is a symbiotic association of soil fungus and the roots of higher plants.

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