Which nucleotide base pairs with adenine in DNA?

In DNA, adenine (A) pairs with thymine (T) through two hydrogen bonds. This specific pairing is essential for the structure of DNA, as it helps maintain the double helix configuration by ensuring that the width of the helix remains uniform. The complementarity of the base pairs—adenine with thymine and guanine with cytosine—contributes to the stability of the DNA molecule and is vital for accurate DNA replication during cell division.

Other nucleotide bases do not pair with adenine in DNA. Cytosine, for example, pairs with guanine, while uracil is found in RNA instead of thymine, serving a similar pairing role with adenine.