Template:POTD/2012-11-17
A diagram showing the structure of DNA, with detail showing the structure of the four bases: adenine, cytosine, guanine and thymine, and the location of the major and minor groove. Along with RNA and proteins, DNA is one of the three major macromolecules that are essential for all known forms of life. Most DNA molecules are double-stranded helices, consisting of two long polymers of simple units called nucleotides, molecules with backbones made of alternating sugars (deoxyribose) and phosphate groups, with the bases attached to the sugars.Image: Richard Wheeler