Restriction endonucleases are commonly called as

Options

A. Molecular scissors
B. Molecular knives
C. Nature's scalpels
D. All

Answer

### Step-by-Step Solution:

1. **Understanding Restriction Endonucleases**:
- Restriction endonucleases are enzymes that cut DNA at specific sequences. They are essential tools in molecular biology for manipulating DNA.

2. **Function of Restriction Endonucleases**:
- These enzymes cleave DNA at internal sites, which is why they are categorized as endonucleases. They play a crucial role in genetic engineering and recombinant DNA technology.

3. **Common Names**:
- Due to their function of cutting DNA, restriction endonucleases are commonly referred to as "molecular scissors." This term highlights their ability to cut DNA strands precisely.
- Additionally, they can also be called "molecular knives" and "nature's scalpels" because they perform similar functions of cutting and are found naturally in bacteria.

4. **Conclusion**:
- Therefore, the common names for restriction endonucleases include molecular scissors, molecular knives, and nature's scalpels. All these terms reflect their role in DNA manipulation.

### Final Answer:
Restriction endonucleases are commonly called molecular scissors, molecular knives, and nature's scalpels.

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