Assertion : Mycorrhizae represent a mutually beneficial interspecific interaction of fungi with roots of higher plants.
Reason : In a mutualistic relationship, both the organisms enter into some sort of physiological exchange.

Explanation

To analyze the assertion and reason provided in the question, we will break down the information step by step.

### Step 1: Understanding the Assertion
The assertion states that "Mycorrhizae represent a mutually beneficial interspecific interaction of fungi with roots of higher plants."

- Mycorrhizae are associations between fungi and plant roots.
- This relationship is beneficial for both organisms involved. The fungi receive carbohydrates from the plant, while the plant benefits from increased nutrient and water absorption facilitated by the fungal hyphae.

### Step 2: Understanding the Reason
The reason states that "In a mutualistic relationship, both the organisms enter into some sort of physiological exchange."

- Mutualism is a type of symbiotic relationship where both species benefit.
- In mycorrhizae, the physiological exchange occurs as the plant provides organic compounds (like sugars) to the fungi, and in return, the fungi enhance the plant's nutrient uptake (especially phosphorus and other minerals).

### Step 3: Analyzing the Relationship Between Assertion and Reason
- Both the assertion and the reason are correct statements.
- The assertion correctly describes mycorrhizae as a mutualistic relationship, while the reason accurately explains that mutualistic relationships involve physiological exchanges.

### Step 4: Conclusion
Since both the assertion and the reason are true and the reason correctly explains the assertion, we conclude that both statements support each other.

### Final Answer
Both the assertion and the reason are correct, and the reason supports the assertion.

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