DNA fragments generated by the restriction endonucleases in a chemical reaction can be separated by :

Options

A. Electrophoresis
B. Restriction mapping
C. Centrifugation
D. Polymerase chain reaction

Answer

To solve the question regarding how DNA fragments generated by restriction endonucleases can be separated, we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Restriction Endonucleases**:
- Restriction endonucleases are enzymes that cut DNA at specific sequences. This results in the generation of DNA fragments of varying lengths depending on where the cuts are made.

2. **Identifying Separation Techniques**:
- The question presents four options: electrophoresis, restriction mapping, centrifugation, and polymerase chain reaction (PCR). We need to identify which of these techniques is used for separating DNA fragments.

3. **Evaluating Each Option**:
- **Electrophoresis**: This technique uses an electric field to move DNA fragments through a gel (usually agarose). The fragments separate based on size, with smaller fragments moving faster than larger ones.
- **Restriction Mapping**: This is a method used to determine the locations of restriction sites within a DNA molecule, not for separating fragments.
- **Centrifugation**: This technique separates substances based on density, which is not specific for DNA fragment separation.
- **Polymerase Chain Reaction (PCR)**: PCR is a method for amplifying DNA, not for separating fragments.

4. **Conclusion**:
- The most appropriate method for separating DNA fragments generated by restriction endonucleases is **electrophoresis**.

### Final Answer:
DNA fragments generated by restriction endonucleases in a chemical reaction can be separated by **electrophoresis**.

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