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.
So, 165 km is about the lowest reasonable orbit. There are satellites orbiting at many altitudes up to 35,600 km, which is the height for geosynchronous orbits) and there have been satellites orbiting much higher (either for some scientific purpose or some accident).