The substrate for restriction enzyme is-

Options

A. Single standed RNA
B. Proteins
C. Double standed DNA
D. Single stranded DNA

Answer

To answer the question regarding the substrate for restriction enzymes, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Restriction Enzymes**:
- Restriction enzymes, also known as restriction endonucleases, are enzymes that cut DNA at specific sequences known as restriction sites.

2. **Identifying the Substrate**:
- The substrate for restriction enzymes is the type of nucleic acid they act upon. Common substrates include DNA and RNA.

3. **Analyzing the Options**:
- The options given are:
- A) Single-stranded RNA
- B) Proteins
- C) Double-stranded DNA
- D) Single-stranded DNA

4. **Evaluating Each Option**:
- **Single-stranded RNA**: Restriction enzymes do not act on RNA. This option is incorrect.
- **Proteins**: Restriction enzymes do not cleave proteins. This option is incorrect.
- **Double-stranded DNA**: This is the correct substrate for restriction enzymes, as they specifically cleave double-stranded DNA at defined sites.
- **Single-stranded DNA**: While some enzymes can act on single-stranded DNA, restriction enzymes primarily target double-stranded DNA. This option is incorrect.

5. **Conclusion**:
- Based on the analysis, the correct answer is **C) Double-stranded DNA**.

### Final Answer:
The substrate for restriction enzyme is **C) Double-stranded DNA**.

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