Lichens represents an intimate mutualistic relationship between

Options

A. fungus and bacteria
B. fungus and photosynthetic algae
C. fungus and archaebacteria
D. fungus and plants

Answer

To solve the question regarding the intimate mutualistic relationship represented by lichens, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Lichens**:
- Lichens are not single organisms; they are a symbiotic association between two different organisms.

2. **Identifying the Organisms Involved**:
- The two main components of lichens are fungi and a photosynthetic partner, which is usually algae or cyanobacteria.

3. **Defining Mutualism**:
- Mutualism is a type of symbiotic relationship where both organisms benefit from each other. In the case of lichens, the fungus and the photosynthetic partner both gain advantages.

4. **Roles of the Organisms**:
- The fungus (mycobiont) provides structure, protection, and absorbs water and minerals from the environment.
- The photosynthetic partner (phycobiont), typically algae, produces food through photosynthesis, which nourishes both organisms.

5. **Analyzing the Options**:
- A. Fungus and bacteria: Incorrect, as lichens do not primarily involve bacteria.
- B. Fungus and photosynthetic algae: Correct, as this accurately describes the relationship in lichens.
- C. Fungus and archaebacteria: Incorrect, as archaebacteria are not involved in the lichen structure.
- D. Fungus and plants: Incorrect, as lichens specifically involve fungi and algae, not plants.

6. **Conclusion**:
- Based on the analysis, the correct answer is **B. Fungus and photosynthetic algae**.

### Final Answer:
Lichens represent an intimate mutualistic relationship between **fungus and photosynthetic algae**.

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