What is a Base Pair?
Human DNA consists of about 3 billion bases, and more than 99 percent of those bases are the same in all people. The order, or sequence, of these bases determines the information available for building and maintaining an organism, similar to the way in which letters of the alphabet appear in a certain order to form words and sentences. DNA bases pair up with each other, A with T and C with G, to form units called base pairs. For example, two nitrogenous bases (adenine and thymine or guanine and cytosine) held together by weak bonds is called a base pair. Two strands of DNA are held together in the shape of a double helix by the bonds between base pairs.
