The cells that make up all living things contain three basic elements. There are molecules that encode genetic information and can be copied; DNA and RNA. There are proteins; the molecules that perform important tasks. And encapsulating them all, there is a membrane made from fatty acids. Life arose in saltwater, which destabilizes membranes. Furthermore, magnesium ions, which are required for RNA, also destabilize membranes. Scientists think that they may have solved the mystery what stabilized membranes – amino acids. The findings were published in the journal Proceedings of the National Academy of Sciences.