single-letter designation of the pyrimidine base cytosine; also used in diagrams to represent a nucleotide containing cytosine


the structure by which hereditary information is physically transmitted from one generation to the next; the organelle that carries the genes


tests performed in parallel with experimental samples and designed to demonstrate that a procedure worked correctly


a pyrimidine base; one of the four nitrogen-containing molecules in nucleic acids DNA and RNA; designated by the letter C


the breaking down of DNA by chemical or physical means


the process of unfolding of the complementary double strands of DNA to form single strands

Deoxyribonucleic acid (DNA)

the genetic material of organisms, usually double-stranded—composed of two complementary chains of nucleotides in the form of a double helix; a class of nucleic acids characterized by the presence of the sugar deoxyribose and the four bases adenine, cytosine, guanine, and thymine

Diallelic DNA

variation showing only two forms with a frequency of more than 1%


having two sets of chromosomes, in pairs (compare haploid)


deoxyribonucleic acid

DNA band

the visual image representing a particular DNA fragment on an autoradiogram

DNA databank (database)

a collection of DNA typing profiles of selected or randomly chosen individuals

DNA polymerase

an enzyme that catalyzes the synthesis of double-stranded DNA

DNA probe

a short segment of single-stranded DNA labeled with a radioactive or chemical tag that is used to detect the presence of a particular DNA sequence through hybridization to its complementary sequence


a technique in which different molecules are separated by their rate of movement in an electric field


a protein that is capable of speeding up a specific chemical reaction but which itself is not changed or consumed in the process; a biological catalyst

Ethidium bromide

an organic molecule that binds to DNA and fluoresces under ultraviolet light and is used to identify DNA


single-letter designation of the purine base guanine; also used in diagrams to represent a nucleotide containing guanine


a haploid reproductive cell

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