Nucleic acids are a type of polymers (macromolecules). Nucleic acids may be the DNA (deoxyribonucleic acid) or RNA (ribonucleic acid). The DNA stores genetic information while RNA translates this information into proteins.
The building blocks of nucleic acids are called nucleotides. These are organic molecules composed of a base, a five-membered carbon ring (sugar), and a phosphate group. The bases that comprise monomers of the DNA are adenine (A), guanine (G), cytosine (C), and Thymine (T). For RNA's, Thymine is replaced by Uracil (U), and the rest are the same.
The sugar is either deoxyribose for DNA or ribose for RNA. A base bound to the sugar is called a nucleoside.
The nucleoside then is bound to a triphosphate group to create the nucleotide, which are the monomers, or the repeating units for the nucleic acids.