Gel Electrophoresis Process Case Study

1. How does the process of gel electrophoresis separate DNA fragments?

It uses an electric current to separate different-sized molecules in a porous, sponge-like matrix.

2. What is the purpose of the agarose gel?

It is used to separate DNA molecules that range in different lengths.

3. What is the purpose of adding blue “tracking” dye to the DNA samples?

The blue tracking dye is added to help load the samples easily and helps able to see the DNA moving through the gel.

4. Explain why DNA has an overall negative charge.

The phosphate groups in the DNA backbone carry negatively-charged oxygens, which overall makes it negatively charged.

5. Why is the fact that DNA has a negative charge so important in the gel electrophoresis process?