A Eukaryote used as food by astronauts

Options

A. Chlorella
B. spirulina
C. Saccharomyces
D. Chaetomium

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a eukaryote that is used as food by astronauts. We need to identify which of the given options fits this description.

2. **Analyzing the Options**:
- **Option 1: Chlorella**: This is a type of green algae that is known for its high nutritional value, containing about 45% proteins, 20% carbohydrates, and various vitamins and minerals. It is considered a superfood and is beneficial for astronauts as it enhances the immune system and provides essential nutrients.
- **Option 2: Spirulina**: Although Spirulina is a dietary supplement, it is a prokaryote (cyanobacteria) and not a eukaryote. Therefore, it cannot be the correct answer.
- **Option 3: Saccharomyces**: This is a genus of fungi, commonly known as yeast. While it is a eukaryote, it is not typically consumed directly as food but is used in fermentation processes. Thus, it is not the answer we are looking for.
- **Option 4: Ketomium**: This is a dangerous organism that can cause infections in humans. It is not edible and is not used as food, making it an incorrect option.

3. **Conclusion**: After analyzing all the options, the only eukaryote that is used as food by astronauts is **Chlorella**.

**Final Answer**: Chlorella

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