Definition: The genetic material of the nucleus consisting of deoxyribonucleoprotein that occurs in two forms during the phase between mitotic divisions: as heterochromatin, seen as condensed, readily stainable clumps; as euchromatin, dispersed lightly staining or nonstaining material. During mitotic division the chromatin condenses into chromosomes.
[G. chroma, color]
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Examples: glitazone, GI cocktail, etc.