Noun
The word is derived from chiasma
At this stage, non-sister chromatids may cross-over at points called chiasmata (plural; singular chiasma ). Source: Internet
Because the chromosomes cannot be distinguished in the synaptonemal complex, the actual act of crossing over is not perceivable through the microscope, and chiasmata are not visible until the next stage. Source: Internet
Sites of crossing over entangle together, effectively overlapping, making chiasmata clearly visible. Source: Internet
The chiasmata remain on the chromosomes until they are severed at the transition to anaphase I. In mammalian and human fetal oogenesis all developing oocytes develop to this stage and are arrested before birth. Source: Internet
At the sites where exchange happens, chiasmata form. Source: Internet