chiasma(redirected from chiasma syndrome)
Also found in: Dictionary, Thesaurus, Medical.
Related to chiasma syndrome: Wilbrand's knee
chiasma(kīăz`mə): see crossing overcrossing over,
process in genetics by which the two chromosomes of a homologous pair exchange equal segments with each other. Crossing over occurs in the first division of meiosis. At that stage each chromosome has replicated into two strands called sister chromatids.
..... Click the link for more information. .
A cross-shaped point of intersection of two parts, especially of the optic nerves.
(cell and molecular biology)
The point of junction and fusion between paired chromatids or chromosomes, first seen during diplotene of meiosis.