Question

How are DNA fragments separated and isolated?

Hint:

Gel electrophoresis separates DNA based on size; smaller fragments travel faster.

Answer 1

Step 1: Separation method.
DNA fragments are separated by a technique called gel electrophoresis. Agarose gel acts as a medium.
Step 2: Principle.
DNA is negatively charged (due to phosphate groups). When an electric field is applied, DNA fragments move towards the positive electrode. Smaller fragments move faster than larger ones.
Step 3: Visualization.
DNA fragments are stained with ethidium bromide or other dyes and visualized under UV light.
Step 4: Isolation.
The specific DNA fragment is cut out from the gel and extracted for further use.
Step 5: Conclusion.
Gel electrophoresis allows both separation and isolation of DNA fragments.