An alga which can be possible used in space flight (Space Alga) is

Options

A. Nostoc
B. Chlorella
C. Ulothrix
D. Spirogyra.

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for an alga that is referred to as "space alga" and can potentially be used in space flight.

2. **Identifying the Options**: The options provided are:
- A) Nostochlorella
- B) Eulothrix
- C) Pyrogera

3. **Analyzing Each Option**:
- **Nostochlorella**: This is a cyanobacterium (often referred to as blue-green algae) that is primarily known for its role in nitrogen fixation. It is not typically associated with space applications.
- **Eulothrix**: This is a green alga, but it does not have significant nutritional value or any known application in space environments.
- **Chlorella**: This is a genus of green algae that is known for its high protein content and nutritional value. It is also capable of photosynthesis, which allows it to absorb carbon dioxide and release oxygen—an essential process for maintaining a breathable atmosphere in space.

4. **Conclusion**: Based on the analysis, Chlorella is the alga that is commonly referred to as "space alga" due to its nutritional benefits and its ability to create a conducive environment for astronauts by recycling carbon dioxide into oxygen.

5. **Final Answer**: The correct answer is **Chlorella**.

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