Tiebreakers_  The APC/C, or cyclosome, is activated at the end of this process, and cyclin B is attached to ubiquitin, which marks it to be destroyed by proteasomes. This deactivates maturation-promoting factor. Sister chromatids are held together by cohesin, and the inhibition of separase through the presence of securin during this process prevents cohesin from breaking down. A checkpoint during 
Tiebreakers_  The APC/C, or cyclosome, is activated at the end of this process, and cyclin B is attached to ubiquitin, which marks it to be destroyed by proteasomes. This deactivates maturation-promoting factor. Sister chromatids are held together by cohesin, and the inhibition of separase through the presence of securin during this process prevents cohesin from breaking down. A checkpoint during it detects any failure of fibers from the mitotic spindle to attach to kinetochores. For ten points, name this phase of mitosis in which the condensed sister chromatids align at the equatorial plate, and occurs between prophase and anaphase.
Tiebreakers_  The APC/C, or cyclosome, is activated at the end of this process, and cyclin B is attached to ubiquitin, which marks it to be destroyed by proteasomes.
{metaphase}