DNA stands for Deoxyribonucleic Acid. DNA is the molecule that carries the genetic instructionsused in the growth, development, functioning, and reproduction of all living organisms and manyviruses. DNA is made up of two long chains of nucleotides, which are the building blocks ofDNA. The nucleotides are made up of a sugar molecule, a phosphate group, and a nitrogenousbase. The nitrogenous base is the part of the nucleotide that determines the genetic informationencoded in the DNA. There are four nitrogenous bases in DNA: adenine (A), guanine (G),cytosine (C), and thymine (T). These bases pair up in a specific way (A with T and C with G) toform the familiar double helix structure of DNA. The sequence of the four nitrogenous bases inthe DNA molecule determines the genetic code and is responsible for the diversity of life onEarth.