Lichens are symbiotic associations between a fungus and algae. Most of these lichens consist of:

Options

A. Red algae and ascomycetes
B. Brown algae and phycomcetes
C. Blue - green algae and basidomycetes
D. Blue - green algae and ascomycetes

Answer

**Step-by-Step Solution:**

1. **Understanding Lichens**: Lichens are composite organisms formed by a symbiotic relationship between two different types of organisms: a fungus and an alga (or cyanobacteria).

2. **Identifying the Components**: The two main components of lichens are:
- **Fungi**: The fungal partner provides structure and protection.
- **Algae or Cyanobacteria**: The algal partner (often green algae or cyanobacteria) performs photosynthesis, producing food that the fungus can use.

3. **Function of Each Component**:
- The algae (or cyanobacteria) carry out photosynthesis, converting light energy into chemical energy in the form of glucose.
- The fungus benefits from this process by receiving nutrients, while providing a suitable environment for the algae to thrive.

4. **Common Associations**: Most lichens are primarily associated with blue-green algae (cyanobacteria) rather than just green algae. This is an important distinction because it highlights the specific type of algae that is most commonly found in lichens.

5. **Conclusion**: Based on the information, the correct answer to the question "Most of these lichens consist of" is that they primarily consist of a symbiotic association between fungi and blue-green algae (cyanobacteria).

**Final Answer**: Most lichens consist of a symbiotic association between fungi and blue-green algae (cyanobacteria).

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