To understand how the origin of life relates to biosensors, you need to understand a little about the chemistry of the origin of life. Today, virtually all organisms use DNA to encode genetic information, and proteins to carry out the day-to-day operations of the cell. The molecule that carries information from DNA and allows it to be decoded into a protein is called RNA.

• DNA is a long, double-stranded molecule twisted into a helix. It is composed of a chemical code (represented by the letters A, T, G, and C) that describes how to make proteins.
• RNA is similar to DNA, but it is shorter and single-stranded. RNA can carry an “imprint” of DNA information and take it to the place in the cell where proteins are built.
• Proteins are long chain-like molecules that fold into complicated shapes and perform all sorts of jobs in the cell — from providing raw building materials to running chemical reactions. They are the workhorses of the cell — and, hence, of the organism.