DNA components. Computer artwork showing the structure of the two molecules that make up the backbone of DNA (deoxyribonucleic acid), phosphate (left) and deoxyribose (right). Atoms are represented by colour-coded spheres: carbon (green), oxygen (red), nitrogen (blue), hydrogen (white), with the bonds between them as rods. Within DNA, phosphates and deoxyriboses come together to form the frame or 'backbone' of the molecule. The other components (not shown) of DNA are the four nitrogenous bases: cytosine, guanine, adenine and thymine.