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Related to karyosome: excystation


An irregular aggregation of chromatin in the nucleus of a cell not undergoing mitosis.


1. (Biology) any of the dense aggregates of chromatin in the nucleus of a cell
2. (Biology) the nucleus of a cell


(ˈkær i əˌsoʊm)

any of several masses of chromatin in the reticulum of a cell nucleus.
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References in periodicals archive ?
There is one nucleus with a large blot-like karyosome and no peripheral chromatin.
Karyosome A structure within the nuclue of amoebae having a relatively constant size and location in each species.
When the case was referred to the parasitology laboratory (Infectious Diseases Department, Pavia University Hospital), a definitive diagnosis of PAM was made on the basis of morphology of amebic trophozoites, which exhibited a conspicuous karyosome, a vacuolated cytoplasm, and a mean diameter of 10 [micro]m to 12 gm.