Definition of Polymerase Chain Reaction
Polymerase Chain Reaction is a technique that is employed when a large number of clones of a particular region of DNA are to be made. PCR has the ability to generate millions of copies in a very short period of time.
The PCR depends upon the DNA primers which are specifically designed for the particular DNA region and on a DNA polymerase which is known as Taq polymerase. Taq polymerase has an ability to withstand a great amount of heat and it is extracted from a thermophilic bacterium named Thermus aquaticus. This technique is used in cloning DNA fragments, in forensic analysis and in medical diagnostics.