High resolution

Module 9: Figure chromosome separation

Control of chromosome separation at anaphase.

The spindle checkpoint ensures that the cell cycle is arrested at metaphase until all the chromatids are lined up on the metaphase plate. The onset of chromosome separation, which marks the beginning of anaphase, is triggered by a specific stimulus. There are indications that a surge in the level of Ca2+ may be responsible for activating the anaphase-promoting complex (APC) through the sequence of events described in the text.