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.
Â· just now. 1  Most instrument have this item marked on it. 2  Least count is the minimum measurement which can be taken accurately by a measuring device.It is the. 3  Least count is the smallest measurement which can be measured using that instrument. 4  In the metric system, 0.02 mm.