Explain the types of restriction enzymes.

Explanation

A restriction enzyme, which is able to cut DNA molecules into fragments at desired site within the molecule known as restriction sites. They are classified into Exonucleases and Endonucleases based on their mode of action.
(i) Endonucleases are the enzymes responsible for removing one nucleotide at a time from the end of a DNA molecule. Eg: Bal 31, Exonuclease II
(ii) Endonucleases are enzymes that break the iternal phosphodiester bonds within DNA molecule Eg: Hind II, EcoRI, Pvul,BamHI, Taql.