DNA (deoxyribonucleic acid)
One of two types of molecules that encode genetic information. (The other is RNA. In humans DNA is the genetic material; RNA is transcribed from it. In some other organisms, RNA is the genetic material and, in reverse fashion, the DNA is transcribed from it.) DNA is a double-stranded molecule held together by weak hydrogen bonds between base pairs of nucleotides. The molecule forms a double helix in which two strands of DNA spiral about one other. The double helix looks something like an immensely long ladder twisted into a helix, or coil. The sides of the "ladder" are formed by a backbone of sugar and phosphate molecules, and the "rungs" consist of nucleotide bases joined weakly in the middle by the hydrogen bonds. There are four nucleotides in DNA. Each nucleotide contains a base: adenine (A), guanine (G), cytosine (C), or thymine (T). Base pairs form naturally only between A and T and between G and C so the base sequence of each single strand of DNA can be simply deduced from that of its partner strand. The genetic code in DNA is in triplets such as ATG. The base sequence of that triplet in the partner strand is therefore TAC. The first proof that DNA was the hereditary material was provided in 1944 by Oswald Avery, Maclyn McCarty and Colin MacLoed. The double helical structure of DNA was discovered in 1953 by James D. Watson and Francis H.C. Crick with the invaluable collaboration of the X-ray crystallographer Rosalind Franklin. Watson and Crick shared the 1962 Nobel Prize in Physiology or Medicine with Maurice H.F. Wilkins.

Medical dictionary. 2011.

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  • deoxyribonucleic acid — n. a nucleic acid, usually of very high molecular weight, consisting of a linear sequence of monomer units of deoxyribonucleotides, occurring in most organisms in pairs of strands, wound together in the form of a double helix; it is the main… …   The Collaborative International Dictionary of English

  • deoxyribonucleic acid — deoxyribonucleic acid. = DNA (см.). (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • deoxyribonucleic acid —  Deoxyribonucleic Acid  (DNA)  Дезоксирибонуклеиновая кислота (ДНК)   Высокополимерное природное соединение, содержащееся в ядрах клеток живых организмов. Молекула ДНК состоит из двух полинуклеотидных цепей, закрученных одна вокруг другой в… …   Толковый англо-русский словарь по нанотехнологии. - М.

  • deoxyribonucleic acid — [dē äks′ə rī΄bō no͞o klē′ik, dē äks′ə rī΄bōnyo͞oklē′ik; dē äks′ə rī΄bō no͞oklā′ik, dē äks′ə rī΄bō nyo͞oklā′ik] n. DNA …   English World dictionary

  • deoxyribonucleic acid — DNA, nucleic acid molecule composed of millions of bonded pairs nucleotides formed into a twisted double helix, molecule which carries the genetic information of an organism or virus …   English contemporary dictionary

  • deoxyribonucleic acid — deoksiribonukleorūgštis statusas T sritis augalininkystė apibrėžtis Biopolimeras, sudarytas iš deoksiribonukleotidų ir saugantis bei perduodantis genetinę informaciją. atitikmenys: angl. deoxyribonucleic acid; DNA rus. дезоксирибонуклеиновая… …   Žemės ūkio augalų selekcijos ir sėklininkystės terminų žodynas

  • deoxyribonucleic acid — (DNA)    The molecule of heredity. DNA is composed of deoxyribonucleic building blocks, each containing a base: Adenine (A), thymine (T), cytosine (C), or guanine (G); a deoxyribose sugar (S); and a phosphate group (P) …   Forensic science glossary

  • deoxyribonucleic acid — DNA. The molecules inside cells that carry genetic information and pass it from one generation to the next. Also called DNA …   English dictionary of cancer terms

  • deoxyribonucleic acid — (DNA; de ok se ri bo nu kle ik) The nucleic acid that constitutes the genetic material of all cellular organisms. It is a polynucleotide composed of deoxyribonucleotides connected by phosphodiester bonds …   Dictionary of microbiology

  • deoxyribonucleic acid — The type of nucleic acid containing deoxyribose as the sugar component and found principally in the nuclei (chromatin, chromosomes) and mitochondria of animal and plant cells, usually loosely bound to protein (hence the …   Medical dictionary

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