In a genetic engineering experiment restriction enzymes can be used for :

Options

A. bacterial DNA only
B. viral DNA only
C. any DNA fragment
D. eukaryotic DNA only

Answer

### Step-by-Step Solution:

1. **Understanding Restriction Enzymes**:
- Restriction enzymes, also known as restriction endonucleases, are proteins that cut DNA at specific sequences. They are essential tools in genetic engineering.

2. **Types of Restriction Enzymes**:
- There are two main types of restriction enzymes:
- **Exonucleases**: These enzymes remove nucleotides from the ends of a DNA molecule.
- **Endonucleases**: These enzymes cut the DNA at specific internal sites within the molecule.

3. **Function of Endonucleases**:
- Endonucleases are particularly important in genetic engineering because they cut DNA at specific sequences, typically recognizing palindromic sequences that are usually six base pairs long. For example, the sequence GATC is a common recognition site.

4. **Application in Genetic Engineering**:
- In genetic engineering experiments, restriction enzymes are used to cut DNA into manageable fragments. This allows scientists to manipulate DNA, such as inserting genes into plasmids or creating recombinant DNA.

5. **Versatility of Restriction Enzymes**:
- Restriction enzymes can act on any type of DNA, whether it is viral, bacterial, or eukaryotic. This makes them versatile tools in various genetic engineering applications.

### Final Answer:
In a genetic engineering experiment, restriction enzymes are used to cut DNA at specific sequences, allowing for the manipulation and recombination of genetic material.

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