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base pairs

Monday 17 October 2005

Definition: Two nitrogenous (purine or pyrimidine) bases (adenine and thymine or guanine and cytosine) held together by weak hydrogen bonds.

Two strands of DNA are held together in the shape of a double helix by the bonds between base pairs. The number of base pairs is often used as a measure of length of a DNA segment, eg 500 bp.

See also

- deoxyribonucleic acid (DNA)
- nucleotide