DNA is a macromolecule found in cell nuclei that controls the type of cell and organism formed. It is made up of nucleotides, each containing a phosphate group, deoxyribose sugar, and a nitrogenous base. The four bases are adenine, thymine, cytosine, and guanine. Nucleotides bond together in a chain with the bases pairing - adenine with thymine and cytosine with guanine. These paired strands coil together into the iconic double helix structure of DNA.