Which of the following is not true for Nostoc

Options

A. Autotrophic
B. Filamentous
C. Macroscopic
D. Prokaryotic.

Answer

To determine which statement is not true for Nostoc, we will analyze each of the given options: autotrophic, filamentous, macroscopic, and prokaryotic.

### Step-by-Step Solution:

1. **Understanding Nostoc**:
- Nostoc is a genus of cyanobacteria, which are often referred to as blue-green algae. They are primarily found in aquatic environments and can also be found in moist soils.

2. **Analyzing the Options**:
- **Autotrophic**: Nostoc is autotrophic, meaning it can produce its own food through photosynthesis. This is true as they contain chlorophyll.
- **Filamentous**: Nostoc has a filamentous structure, consisting of chains of cells that are cylindrical in shape. This is also true.
- **Macroscopic**: This term refers to organisms that can be seen with the naked eye. Nostoc is generally microscopic, as it is made up of small filaments that are not visible without magnification.
- **Prokaryotic**: Nostoc is indeed prokaryotic, meaning it lacks a well-defined nucleus and other membrane-bound organelles.

3. **Conclusion**:
- The statement that is not true for Nostoc is "macroscopic," as Nostoc is primarily microscopic.

### Final Answer:
The statement that is not true for Nostoc is **macroscopic**.

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