Function of restriction endonuclease enzyme is

Options

A. It is useful in genetic engineering
B. It protects the bacterial DNA against foreign DNA
C. It is helpful in transcription
D. It is helpful in protein synthesis

Answer

**Step-by-Step Solution:**

1. **Understanding Restriction Endonucleases**:
- Restriction endonucleases, also known as restriction enzymes, are proteins that cut DNA at specific sequences. They are crucial tools in molecular biology.

2. **Identifying Functions**:
- The primary function of restriction endonucleases is to recognize specific sequences in DNA and cleave the DNA at those sites. This property is essential for various applications in genetic engineering.

3. **Evaluating the Options**:
- **Option A**: "It is useful in genetic engineering."
- This is correct. Restriction endonucleases are widely used in genetic engineering for cloning and manipulating DNA.
- **Option B**: "It protects the bacterial DNA against foreign DNA."
- This is partially true as some restriction enzymes do protect bacteria from foreign DNA, but this is not their primary function.
- **Option C**: "It is helpful in transcription."
- This is incorrect. Transcription is carried out by RNA polymerases, not restriction endonucleases.
- **Option D**: "It is helpful in protein synthesis."
- This is also incorrect. Protein synthesis (translation) does not involve restriction endonucleases.

4. **Conclusion**:
- The correct answer is that the function of restriction endonuclease enzymes is that they are useful in genetic engineering.

**Final Answer**: The function of restriction endonuclease enzyme is that it is useful in genetic engineering.

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