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 smaller number of the fractional scale is the distance on the map, the larger number in the scale is the distance on the ground. So if we take our example scale (1:62500) we can choose units we want to measure distance in. Lets chose inches.