DNA and RNA

DNA The compound deoxyribonucleic acid a complex organic chemical with a spiral, double-helix structure. It is the 'brains' behind the workings of the living cell, and is made up of chains of nucleotides.

RNA The abbreviation for ribonucleic acid. It is an essential constituent of the living cell, where it carries 'instruction' from the DNA. It is made up of long chains of nucleotides.