Which one is regarded as a molecular scissors in biotechnology?

Options

A. Reverse transcriptase
B. Restriction endomuclease
C. Taq polymerase
D. Topoisomerase

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks which enzyme is referred to as "molecular scissors" in biotechnology. This term typically refers to an enzyme that can cut DNA at specific sites.

2. **Analyzing the Options**:
- **Reverse Transcriptase**: This enzyme synthesizes DNA from RNA. It is involved in the process of reverse transcription but does not cut DNA.
- **Restriction Endonuclease**: These enzymes cut DNA at specific sequences known as restriction sites. This is a key function in genetic engineering, allowing for the insertion of genes into vectors.
- **Taq Polymerase**: This enzyme is used in the polymerase chain reaction (PCR) to amplify DNA. It does not cut DNA.
- **Topoisomerase**: This enzyme helps in untangling DNA and relieving supercoiling during DNA replication, but it does not cut DNA in the same manner as restriction enzymes.

3. **Identifying the Correct Answer**: Based on the analysis, the enzyme that fits the description of "molecular scissors" is the **Restriction Endonuclease**. These enzymes are specifically designed to cut DNA at predetermined locations, making them essential tools in biotechnology.

4. **Conclusion**: Therefore, the answer to the question is **Restriction Endonuclease**, as it is the enzyme regarded as molecular scissors in biotechnology.

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