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A nucleic acid that carries the genetic information in cells and some viruses, consisting of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine. DNA sequences are replicated by the cell prior to cell division and may include genes, intergenic spacers, and regions that bind to regulatory proteins.
(Biochemistry) deoxyribonucleic acid; a nucleic acid that is the main constituent of the chromosomes of all organisms (except some viruses). The DNA molecule consists of two polynucleotide chains in the form of a double helix, containing phosphate and the sugar deoxyribose and linked by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine. DNA is self-replicating, plays a central role in protein synthesis, and is responsible for the transmission of hereditary characteristics from parents to offspring. See also genetic code
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deoxyribonucleic acid: an extremely long, double-stranded nucleic acid molecule arranged as a double helix that is the main constituent of the chromosome and that carries the genes as segments along its strands: found chiefly in the chromatin of cells and in many viruses.
Short for deoxyribonucleic acid. The nucleic acid that is the genetic material determining the makeup of all living cells and many viruses. It consists of two strands of nucleotides linked together in a structure resembling a ladder twisted into a spiral. In eukaryotic cells, the DNA is contained mainly in the nucleus and mitochondria. DNA can replicate itself and synthesize RNA. Compare RNA. See Note at gene.
Did You Know? One of the wonders of nature is that the complexity and diversity of life can be contained in a molecule with a relatively simple structure. Deoxyribonucleic acid, commonly called DNA, exists mainly in the nucleus and mitochondria of each cell in an organism. It consists of two long strands linked together in a structure resembling a ladder twisted into a spiral, called a double helix. Each rung is made up of two chemical bases, called nucleotides, that are joined together by hydrogen bonds. There are four kinds of nucleotides in a DNA molecule: cytosine, guanine, adenine, and thymine—C, G, A, and T, for short. Specific sequences of these bases, known as genes, form codes that contain all of an organism's genetic information. When other components of a cell "read" this code, they produce proteins, the building blocks of life.
deoxyribonucleic acid.See also: Heredity
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|Noun||1.||DNA - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information; "DNA is the king of molecules"|
cistron, gene, factor - (genetics) a segment of DNA that is involved in producing a polypeptide chain; it can include regions preceding and following the coding DNA as well as introns between the exons; it is considered a unit of heredity; "genes were formerly called factors"
operon - a segment of DNA containing adjacent genes including structural genes and an operator gene and a regulatory gene
biochemistry - the organic chemistry of compounds and processes occurring in organisms; the effort to understand biology within the context of chemistry
base pair - one of the pairs of chemical bases joined by hydrogen bonds that connect the complementary strands of a DNA molecule or of an RNA molecule that has two strands; the base pairs are adenine with thymine and guanine with cytosine in DNA and adenine with uracil and guanine with cytosine in RNA
adenine, A - (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
cDNA, complementary DNA - single-stranded DNA that is complementary to messenger RNA or DNA that has been synthesized from messenger RNA by reverse transcriptase
episome - DNA that is not incorporated into the genome but is replicated together with the genome (especially in bacterial cells)
coding DNA, exon - sequence of a gene's DNA that transcribes into protein structures; "exons are interspersed with introns"
junk DNA - stretches of DNA that do not code for genes; "most of the genome consists of junk DNA"
recombinant deoxyribonucleic acid, recombinant DNA - genetically engineered DNA made by recombining fragments of DNA from different organisms
sticky end - an end of DNA in which one strand of the double helix extends a few units beyond the other
jumping gene, transposon - a segment of DNA that can become integrated at many different sites along a chromosome (especially a segment of bacterial DNA that can be translocated as a whole)
nucleic acid - (biochemistry) any of various macromolecules composed of nucleotide chains that are vital constituents of all living cells
polymer - a naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers