Nucleotides contain either ribose, found in RNA, or deoxyribose, found in DNA. Deoxyribose is not synthesized in the cell, it is produced by action of the enyme ribonucleotided reductase on ribonucleotide diphoshates. Ribose is the product of the pentose phosphate pathway.
A nucleotide is made up of three things. It consists of a nitrogenous base made up of either adenine, cytosine, guanine or thymine. The nucleotide also contains either the sugar deoxyribose or ribose. Finally, it contains one or more phosphate groups. Nucleotides bond together and form a double helix, which was discovered by scientists Francis Crick and James Watson in 1956.