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

Options

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

Answer

To answer the question "DNA fragments generated by restriction endonucleases in a chemical reaction can be separated by," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks how DNA fragments, which are produced by restriction endonucleases, can be separated.

2. **Identifying the Options**: The options provided are:
- A) Polymerase Chain Reaction (PCR)
- B) Electrophoresis
- C) Restriction Mapping
- D) Centrifugation

3. **Analyzing Each Option**:
- **A) Polymerase Chain Reaction (PCR)**: This technique is used to amplify DNA, not to separate fragments.
- **B) Electrophoresis**: This method separates DNA fragments based on their size by applying an electric field. Since DNA is negatively charged, it moves towards the positive electrode, allowing smaller fragments to travel further than larger ones.
- **C) Restriction Mapping**: This is a technique used to determine the locations of restriction sites within a DNA molecule, not for separating DNA fragments.
- **D) Centrifugation**: This method separates substances based on density, but it is not effective for separating DNA fragments by size.

4. **Conclusion**: Based on the analysis, the correct method for separating DNA fragments generated by restriction endonucleases is **Electrophoresis**.

### Final Answer:
**Electrophoresis**

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