A linear polymer made up of a specific sequence of deoxyribonucleotide repeating units linked by 3′,5′-phosphodiester bonds; it is the carrier of genetic information. The set of DNA molecules that contains all genetic information for an organism is called its genome. DNA is found primarily in the nuclei of eukaryotic cells and in the nucleoid of bacteria. Small amounts of DNA are also found in organelles (such as mitochondria and chloroplasts) that contain their own genomes, in autonomously maintained DNAs called plasmids, and in viruses.