Answer:
PCR is a biochemical process capable of amplifying a single DNA molecule into millions of copies in a short time. Amplification is achieved by a series of three steps: (1) denaturation, in which double-stranded DNA templates are heated to separate the strands; (2) annealing, in which short DNA molecules called primers bind to flanking regions of the target DNA; and (3) extension, in which DNA polymerase extends the 3′ end of each primer along the template strands. These steps are repeated (“cycled”) 25–35 times to exponentially produce exact copies of the target DNA