DNA is made up of long chains of nucleotides. To make a complete DNA molecule, single nucleotides join to make chains that come together as matched pairs and form long double strands. Each nucleotide is comprised of the following:
A five-sided (pentose) sugar called deoxyribose
A phosphate
One of four nitrogen-rich bases: adenine, guanine, cytosine, or thymine
Nucleotides are joined together by phosphodiester bonds. Nucleotide chains are antiparallel and complementary.
