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.
From top to bottom, Crux measures just 6 degrees â only a little taller than the distance between the pointer stars of the Big Dipper. (Reminder: Your clenchd fist held at arm's length is 10 degrees wide.) In fact, the Southern Cross is the smallest (in area) of all the constellations. Like the Big Dipper of the northern sky, the Southern Cross indicates the location of the pole and as such is often utilized by navigators.