Ulothrix be described as a

Options

A. Filamentous alga lacking flagellated reproductive stages
B. Coenobial alga producing zoospores
C. Filamentous alga with flagellated reproductive stages
D. Non - motile colonial alga lacking zoospores

Answer

To describe Ulothrix, we need to analyze the characteristics of this alga and evaluate the given options step by step.

### Step-by-Step Solution:

1. **Understanding Ulothrix**:
- Ulothrix is a filamentous green alga. It is known for its structure, which consists of long, thread-like filaments.

2. **Identifying Key Features**:
- Ulothrix reproduces sexually and asexually. It is important to note that it produces flagellated gametes during reproduction, specifically through a process called isogamy.

3. **Evaluating the Options**:
- **Option 1**: "Filamentous alga lacking flagellated reproductive stages."
- This option is incorrect because Ulothrix does produce flagellated gametes.

- **Option 2**: "Cynobial alga producing zoospores."
- This option is also incorrect. Ulothrix is not a cyanobacterial alga (cyanobacteria are a different group) and does not primarily produce zoospores.

- **Option 3**: "Filamentous alga with flagellated reproductive stages."
- This option is correct. Ulothrix is indeed filamentous and produces flagellated gametes during reproduction.

- **Option 4**: "Non-motile colonial alga lacking zoospores."
- This option is incorrect as Ulothrix is not non-motile nor does it lack zoospores; it is filamentous and motile due to the presence of flagellated gametes.

4. **Conclusion**:
- After evaluating all options, the correct description of Ulothrix is: **"Filamentous alga with flagellated reproductive stages."**

### Final Answer:
Ulothrix can be described as a filamentous alga with flagellated reproductive stages.

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