Explain briefly:
(a) PCR
(b) Restriction enzymes and DNA
( c) Chitinase

Explanation

PCJt : PCR stands for Polymerase Chain Reaction. In this reaction multiple copies of the gene (or DNA) of interest is synthesised vitro in, using sets of primers and the enzyme Thq DNA Polymerase. Restriction Enzymes and DNA : These are the enzymes which restrict the growth of bacteriophages. These enzymes are present in many bacteria where they function as a part of their defence mechanism called Restriction Modification System. Restriction enzymes are of two types : Restriction endonuclease cuts DNA into pieces. Modification enzyme adds methyl group to DNA. Chitlnase : It is an enzyme which breaks down the chitinous substance present in the wall of fungi.