What is the symbiotic assication of a fungus with a root system of higher plants.

Answer

### Step-by-Step Solution:

1. **Definition of Symbiotic Association**: Begin by understanding what a symbiotic association is. It refers to a close and long-term interaction between two different biological species, which can be beneficial for one or both parties involved.

2. **Identify the Organisms Involved**: In this case, the two organisms involved are fungi and the roots of higher plants.

3. **Name of the Symbiotic Association**: The specific term for the symbiotic relationship between fungi and the roots of higher plants is called "mycorrhiza."

4. **Function of Mycorrhiza**: Mycorrhiza plays a crucial role in enhancing the plant's ability to absorb water and essential minerals from the soil. The fungal hyphae extend the root system, increasing the surface area for absorption.

5. **Mutual Benefits**: In this association, the plant benefits by receiving increased water and nutrient uptake, while the fungus benefits from the organic nutrients (like carbohydrates) provided by the plant through photosynthesis.

6. **Conclusion**: Therefore, mycorrhiza is a vital symbiotic relationship that supports plant growth and health, while also providing sustenance to the fungi.