Two nucleotides that are in different nucleic acid chains and whose bases pair (interact) by hydrogen bonding. In DNA, the nucleotide bases are adenine (which pairs with thymine) and guanine (which pairs with cytosine).
A partnership of adenosine with thymidine or cytosine with guanine in a double helix.
In the double-stranded helical arrangement of DNA, the purine bases (i.e., base pairs) that are either an adenine-thymine pair or a guaninecytosine pair. These base pairs connect the helical strands of DNA like the steps of a spiral staircase.
Within a DNA molecule, there exists a section known as a base pair, consisting of two nucleotide bases connected by hydrogen bonds. These base pairs form the “rungs” of the DNA “ladder” structure. Among the four bases, there are only two possible pairings: guanine always pairs with cytosine, and adenine pairs with thymine. The specific sequence of base pairs within each DNA chain serves as the code that governs cellular activities.