Restriction enzymes are isolated chiefly from

Options

A. Prokaryotes
B. protists
C. protozoans
D. fungi

Answer

**Step-by-Step Solution:**

1. **Understanding Restriction Enzymes**:
- Restriction enzymes, also known as molecular scissors, are proteins that cut DNA at specific sequences. They are crucial in molecular biology for cloning, gene editing, and DNA analysis.

2. **Identifying the Source of Restriction Enzymes**:
- The question asks where restriction enzymes are chiefly isolated from. The options provided are:
1. Prokaryotes
2. Protease
3. Protozoans
4. Fungi

3. **Evaluating Each Option**:
- **Prokaryotes**: These are unicellular organisms that lack a nucleus. Restriction enzymes are primarily found in prokaryotes, especially bacteria, as a defense mechanism against foreign DNA (like that from viruses).
- **Protease**: This is not a source of restriction enzymes; rather, proteases are enzymes that break down proteins.
- **Protozoans**: These are eukaryotic organisms and do not primarily produce restriction enzymes.
- **Fungi**: While fungi are eukaryotes, they do not typically produce restriction enzymes like prokaryotes do.

4. **Conclusion**:
- Based on the analysis, the correct answer is that restriction enzymes are chiefly isolated from **prokaryotes**.

**Final Answer**: Restriction enzymes are chiefly isolated from **prokaryotes**.

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