Blue green algae are .... and members of kingdom. ...

Options

A. Photoautotrophs, Protista
B. Photoautotrophs, Monera
C. Chemoautotrophs , Monera
D. Chemoheterotrophs , Protista

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question refers to blue-green algae, which are scientifically known as cyanobacteria.

2. **Classification of Blue-Green Algae**: Blue-green algae are classified under the kingdom Monera. This kingdom includes all prokaryotic organisms, which are characterized by the absence of a defined nucleus.

3. **Characteristics of Blue-Green Algae**: Blue-green algae are photoautotrophs. This means they can produce their own food through photosynthesis, utilizing sunlight. They contain chlorophyll-a, which is the pigment responsible for this process.

4. **Understanding the Options**:
- **Option A**: Photoautotrophs and belongs to kingdom Protista - Incorrect, as blue-green algae are prokaryotic and belong to Monera, not Protista.
- **Option B**: Photoautotrophs and belongs to kingdom Monera - Correct, as they are indeed photoautotrophs and belong to Monera.
- **Option C**: Chemoautotrophs and belongs to kingdom Monera - Incorrect, as blue-green algae are not chemoautotrophs.
- **Option D**: Chemoheterotrophs and belongs to kingdom blue-green algae - Incorrect, as this classification does not apply to blue-green algae.

5. **Conclusion**: The correct answer is that blue-green algae are photoautotrophs and belong to the kingdom Monera.

**Final Answer**: Blue-green algae are photoautotrophs and members of the kingdom Monera.

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