No zoospore formation has been observed in the algal members belonging to :-

Options

A. Chlorophyceae
B. Brown Algae
C. Phaeophyceae
D. Cyanophyceae

Answer

To solve the question regarding which algal members do not exhibit zoospore formation, we can analyze the options provided:

1. **Understanding Zoospore Formation**:
- Zoospores are a type of asexual reproductive structure that are motile and usually have flagella. They are produced by various groups of algae.

2. **Analyzing Each Option**:
- **Chlorophyceae (Green Algae)**: This group is known for producing zoospores, which typically have two identical anterior flagella. Therefore, they do exhibit zoospore formation.
- **Phaeophyceae (Brown Algae)**: Members of this group also reproduce through motile zoospores, which have two lateral flagella. Hence, they also exhibit zoospore formation.
- **Cyanophyceae (Blue-Green Algae)**: This group does not produce zoospores; instead, they reproduce mainly through simple division or fragmentation. However, they are not classified as true algae in the same sense as the others.
- **Sinophyceae**: This group is characterized by a lack of zoospore formation. They reproduce through simple division or fragmentation, similar to cyanophyceae.

3. **Conclusion**:
- Based on the analysis, the algal members that do not form zoospores belong to the **Cyanophyceae** (Blue-Green Algae) or **Sinophyceae**. However, since the question specifically asks for algal members, the most fitting answer is **Cyanophyceae**.

**Final Answer**: Cyanophyceae (Blue-Green Algae)

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