Restriction enzymes are used to cut

Options

A. single standed RNA
B. double stranded DNA
C. single stranded DNA
D. double stranded RNA

Answer

**Step-by-Step Solution:**

1. **Understanding Restriction Enzymes**: Begin by recognizing what restriction enzymes (also known as restriction endonucleases) are. These are proteins that can cut DNA at specific sequences.

2. **Identifying the Type of Nucleic Acid**: The question asks which type of nucleic acid restriction enzymes cut. The options provided are:
- A) Single-stranded RNA
- B) Double-stranded DNA
- C) Single-stranded DNA
- D) Double-stranded RNA

3. **Function of Restriction Enzymes**: Restriction enzymes specifically target and cut double-stranded DNA at particular sequences known as palindromic sequences. This is a crucial function in molecular biology, especially in genetic engineering and cloning.

4. **Location of Restriction Enzymes**: These enzymes are naturally found in bacteria, where they serve as a defense mechanism against viral DNA. This biological role emphasizes their specificity toward DNA.

5. **Conclusion**: Based on the information gathered, it is clear that restriction enzymes are used to cut double-stranded DNA. Therefore, the correct answer to the question is option B) Double-stranded DNA.

**Final Answer**: B) Double-stranded DNA

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