Cyanobacteria of great nutritive value is

Options

A. Gloeocapsa
B. Scytonema
C. Stigonema
D. Spirulina

Answer

To answer the question "Cyanobacteria of great nutritive value is," we will analyze the options provided and identify which cyanobacteria is known for its high nutritional content.

### Step-by-Step Solution:

1. **Understanding Cyanobacteria**:
- Cyanobacteria are photosynthetic prokaryotes, often referred to as blue-green algae. They are capable of photosynthesis and play a significant role in the ecosystem.

2. **Identifying the Options**:
- The options given are:
- A) Gliocapsa
- B) Cytonema
- C) Stegonema
- D) Spirulina

3. **Evaluating Each Option**:
- **Gliocapsa**: This genus secretes a gelatinous sheath around its cells but is not particularly noted for its nutritional value.
- **Cytonema**: This genus forms solitary branched filaments or mats, but again, it is not recognized for high nutritional content.
- **Stegonema**: This genus consists of branched blue to brown cells, but it does not have significant nutritional value.
- **Spirulina**: This is a spiral-shaped cyanobacterium known as a "superfood." It is rich in protein, containing about 67 grams of protein per 100 grams, and includes essential amino acids, calcium, magnesium, and B vitamins.

4. **Conclusion**:
- Based on the nutritional profile, **Spirulina** is the cyanobacteria known for its great nutritive value.

### Final Answer:
The cyanobacteria of great nutritive value is **Spirulina**.

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