Purines

Definition

Purines are one of the two types of nitrogenous bases found in nucleotides, which make up DNA and RNA. The two purines are adenine (A) and guanine (G).

Related terms

Adenine (A):

One of the two purine bases that pairs with thymine in DNA or uracil in RNA.

Guanine (G):

The other purine base that pairs with cytosine in both DNA and RNA.

Nucleotide:

The building block of DNA and RNA consisting of a sugar, a phosphate group, and a nitrogenous base (either a purine or pyrimidine).