DNA can be used to tell people apart because humans differ from each other based on either their DNA sequences or the lengths of repeated regions of DNA. The technique of gel electrophoresis separates DNA by size, thus allowing people to be identified based on analyzing the lengths of their DNA.
Decrease of sebum production will lead to the following dry skin which is less water proof loss of water through the skin through sweating due to lack of barrier increased infection as sebum has antibacterial properties
Explanation: as the muscles shortens due to contraction, the actin filaments from opposite ends of the sarcomere approach each other. So the two Z bands come closer with reduction in length of the sarcomere