Polymerase chain reaction (PCR) is a laboratory technique used to amplify DNA sequences. The method involves using short DNA sequences called primers to select the portion of the genome to be amplified.olymerase chain reaction (PCR) is a laboratory technique used to amplify DNA sequences. The method involves using short DNA sequences called primers to select the portion of the genome to be amplified.
The smallest possible size for anything in the universe is the Planck Length, which is 1.6 x10-35 m across.
The smallest unit of length is a Planck Length. This is the  equivalent of a millionth of a billionth of a billionth of a  billionth of a centimeter. This is too small for t â¦ he human eye to  see without assistance like a microscope. Answered.