Question

How are the DNA fragments separated by gel electrophoresis is visualized and separated for use in constructing recombinant DNA?

Answer 1

DNA molecule is negatively charged, it can be pulled through the gel by an electric field. Small DNA molecules move more quickly through the gel than larger DNA molecules. As they are negatively charged they move towards the anode under an electric field. Then the separated bonds cut from the gel and get extracted by using a conventional technique. The eluted DNA fragments are then purified and used in recombinant DNA.