Which Statement depicts incorrect characteristics of Cyanobacteria ?

Options

A. They have chlorophyll a similar to green plants.
B. They are unicellular, colonial or filamentous from
C. Motile specialized cells " heterocysts" are present which can fix atmosphere nitrogen.
D. They form water bloom in polluted water bodies.

Answer

To determine which statement depicts incorrect characteristics of Cyanobacteria, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Cyanobacteria**:
- Cyanobacteria are prokaryotic organisms classified under the kingdom Monera. They are also known as blue-green algae and are capable of photosynthesis.

2. **Analyzing the Statements**:
- **Statement 1**: "Chlorophyll-A present, Unicellular, Colloidal and Filamentous."
- This statement is correct. Cyanobacteria contain chlorophyll-a and can exist in unicellular, colloidal, and filamentous forms.

- **Statement 2**: "Motile specialized cells for fixing atmospheric Nitrogen."
- This statement is incorrect. While cyanobacteria have specialized cells (like heterocysts) for nitrogen fixation, these cells are not motile. They are stationary and designed specifically for the process of nitrogen fixation.

- **Statement 3**: "Water blooms form in polluted water bodies."
- This statement is correct. Cyanobacteria can proliferate in nutrient-rich (polluted) water, leading to water blooms.

3. **Conclusion**:
- The incorrect statement regarding the characteristics of Cyanobacteria is **Statement 2**, which incorrectly describes the motility of specialized cells responsible for nitrogen fixation.

### Final Answer:
The incorrect statement about Cyanobacteria is: **"Motile specialized cells for fixing atmospheric Nitrogen."**

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