The two micro-organisms which live in symbiotic association in lichens are

Options

A. fungus and protozoa
B. alga and bacteria
C. bacteria and protozoa
D. alga and fungus

Answer

**Step-by-Step Solution:**

1. **Understanding Lichens**: Lichens are a unique association between two different types of organisms. They are often found growing on rocks, trees, and soil.

2. **Identifying the Organisms**: In lichens, the two main types of organisms involved in this symbiotic relationship are:
- **Algae**: These are photosynthetic organisms that can produce their own food using sunlight.
- **Fungi**: These organisms do not perform photosynthesis and rely on other sources for food.

3. **Mutual Benefits**: The relationship between algae and fungi in lichens is mutualistic:
- **Algae** provide food for the fungi through photosynthesis.
- **Fungi** offer protection and a suitable environment for the algae to thrive.

4. **Conclusion**: Therefore, the two microorganisms that live in symbiotic association in lichens are **Algae and Fungi**.

**Final Answer**: The two microorganisms which live in symbiotic association in lichens are Algae and Fungi.

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