Gel electrophoresis is used for

When genomic DNA extracted from any tissue of a plant or animal species is digested with a restriction enzyme, it is cleaved into segments. The segments of different sizes can be separated through gel electrophoresis. Gel electrophoresis involves movement of fragments or molecules from a well created on one edge of the gel. Endonucleases are enzymes that produce internal cuts called cleavage in DNA molecules. A class of endonucleases cleaves DNA only within or near those sites, which have specific base sequences, such endonucleases are known as restriction endonucleases. The selected vector is cut open with a restriction enzyme that has a unique target site located in the sequence where the DNA insert should be integrated to facilitate the selection of recombinant DNA.