PLOS Biology distributes huge advances over the natural sciences. What's more, we push limits. Intended to propel science and the networks who rely on it, we're changing exploration correspondence to fit the examination procedure. Developing article types and strategies enable writers to share the full story behind their science with a worldwide crowd of scientists, teachers, arrangement producers, understanding support gatherings, and general society. Polymerase chain reaction (PCR) is advance technique in recombinant DNA research with impact on molecular cloning and genetics. By PCR a target sequence of DNA can be amplified a billion fold in several hours. The different steps of PCR are Denaturation, Annealing and Primer extension The top open access journals are peer reviewed scholarly journals of advanced technologies in biology and medicine. . By PCR a target sequence of DNA can be amplified a billion fold in several hours. The different steps of PCR are Denaturation, Annealing and Primer extension The top open access journals are peer reviewed scholarly journals of advanced technologies in biology and medicine.