Pyrimidines

Definition

Pyrimidines are one of the two types of nitrogenous bases found in nucleotides, which make up DNA and RNA. The three pyrimidines are cytosine (C), thymine (T), and uracil (U).

Related terms

Cytosine (C):

A pyrimidine base that pairs with guanine in both DNA and RNA.

Thymine (T):

A pyrimidine base that pairs with adenine only in DNA.

Uracil (U):

A pyrimidine base that replaces thymine in RNA; it also pairs with adenine.