cytosine(heterocyclic base, 4-aminopyrimidin-2(1H)-one, which pairs with guanine in DNA and RNA) noun [UK: sˈaɪtəsˌaɪn] [US: sˈaɪɾəsˌaɪn]
citosinanoun {f}DNA is composed of four nucleotides: adenine, thymine, cytosine and guanine. = El ADN se compone de cuatro nucleótidos: adenina, timina, citosina y guanina.