Which of the following groups of algae produces algin

Options

A. Phaeophyceae and chlorophyceae
B. Rhodophyceae and phaeophyeae
C. Chlorophyceae and rhodophyceae
D. Phaeophyceae only.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which group of algae produces algin, a polysaccharide.

2. **Identifying Algin**: Algin, also known as alginic acid, is a polysaccharide that is primarily found in the cell walls of certain algae.

3. **Identifying the Groups of Algae**: The options provided include:
- Pheophyceae (brown algae)
- Chlorophyceae (green algae)
- Rhodophyceae (red algae)

4. **Researching Algin Production**: Algin is predominantly produced by brown algae (Pheophyceae). It is not significantly produced by green algae (Chlorophyceae) or red algae (Rhodophyceae).

5. **Analyzing the Options**:
- Option A: Pheophyceae and Chlorophyceae - Incorrect, as Chlorophyceae does not produce algin.
- Option B: Rhodophyceae and Pheophyceae - Incorrect, as Rhodophyceae does not produce algin.
- Option C: Chlorophyceae and Rhodophyceae - Incorrect, as neither produces algin.
- Option D: Pheophyceae only - Correct, as algin is produced by brown algae.

6. **Conclusion**: The correct answer is that algin is produced by Pheophyceae (brown algae) only.

**Final Answer**: Pheophyceae only.

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