The pigment in blue - green algae is .... Which is the same as the one found in green plants . These blue - green algae are ....

Options

A. Pycocyanin , photoautotrophs
B. Heterocysts , Nitrogen fixers
C. All pigments except Chlorophyll a, photoautotrophs
D. Chlorophyll a , photoautotrophs

Answer

**Step-by-Step Solution:**

1. **Identify the Pigment in Blue-Green Algae:**
- Blue-green algae, also known as cyanobacteria, contain chlorophyll-a as their primary pigment. This pigment is the same as that found in green plants, which is responsible for capturing light energy during photosynthesis.

2. **Understanding the Role of Chlorophyll-a:**
- Chlorophyll-a is crucial for photosynthesis, allowing these organisms to convert sunlight into chemical energy. This characteristic makes them photosynthetic organisms.

3. **Classifying Blue-Green Algae:**
- Blue-green algae are classified as photoautotrophs. This means they can produce their own food using light energy, carbon dioxide, and water.

4. **Additional Characteristics of Blue-Green Algae:**
- Cyanobacteria can exist in various forms, including unicellular, filamentous, and colonial. They can be found in diverse environments such as freshwater, marine, and terrestrial ecosystems.

5. **Conclusion:**
- Therefore, the pigment in blue-green algae is chlorophyll-a, and these organisms are classified as photoautotrophs.

**Final Answer:**
The pigment in blue-green algae is chlorophyll-a, which is the same as the one found in green plants. These blue-green algae are photoautotrophs.

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