Molecular biology. The molecule that encodes genetic information in all living cells. DNA consists of deoxyribose connected with one of the organic bases adenine (A), guanine (G), cytosine (C), or thymine (T), linked by phosphodiester bounds. DNA occurs in the majority of cases as a double-stranded molecule held together by hydrogen-bonds between A and T and between G and C. The genetic information is encoded in the sequence of bases of the single-strand. DNA is identically duplicated by replication.