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cytosine

Wikipedia

After German Cytosin, equivalent to Ancient Greek κύτος (kútos) + -ine. Cytosine was discovered and named by the German biochemists Albrecht Kossel and Albert Neumann in 1894 when it was hydrolyzed from calf thymus tissues.

• IPA^(key): /ˈsaɪtəsiːn/

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cytosine (plural cytosines)

1. (biochemistry) A heterocyclic base, 4-aminopyrimidin-2(1H)-one, which pairs with guanine in DNA and RNA (by means of three hydrogen bonds).

   Hypernyms: nucleobase, pyrimidine

   Coordinate terms: adenine, guanine, thymine, uracil

   • 1997, Ian McEwan, Enduring Love, Vintage (1998), page 164:

     Then he found them, the substances that made up the four-letter alphabet in whose language all life is written — adenine and cytosine, guanine and thymine.