Fragments of DNA formed after treatment with endonucleases are separated by the technique

Options

A. Polymerase chain reaction
B. Southern blotting
C. Colony hybridisation
D. Electrophoresis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the technique used to separate DNA fragments that are formed after treatment with endonucleases. Endonucleases are enzymes that cut DNA at specific sites, resulting in fragments.

2. **Analyzing the Options**:
- **Polymerase Chain Reaction (PCR)**: This technique is used to amplify DNA, creating millions of copies of a specific DNA segment. It does not separate DNA fragments, so this option is incorrect.
- **Southern Blotting**: This is a method used to identify specific DNA sequences within a sample. While it involves the separation of DNA, it is primarily for detection rather than separation of fragments, making this option incorrect.
- **Colony Hybridization**: This technique is used to identify specific DNA sequences in a colony of cells. It does not focus on the separation of DNA fragments, so this option is also incorrect.
- **Electrophoresis**: Specifically, gel electrophoresis is the technique used to separate DNA fragments based on their size. DNA fragments are negatively charged and move towards a positively charged electrode in a gel matrix, allowing for size-based separation.

3. **Identifying the Correct Answer**: After analyzing all the options, it is clear that the correct technique for separating DNA fragments formed after treatment with endonucleases is **Electrophoresis**.

4. **Conclusion**: Therefore, the answer to the question is **Electrophoresis**.

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