The two homologous chromosomes do not completely separate but remain attached together at one or more points as indicated by X arrangements known as Chiasmata. The displacement of Chiasmata is termed as terminalization. Terminalization is completed in Diakinesis stage.
OR
During diplotene the chiasmata begins to be displaced along the length of the chromosomes .The terminal chiasmata slips of f the ends of the chromosomes and it's position is taken up by an interstitial chiasmata .this process is called terminalisation
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