The separation of sister chromatids into independent daughter chromatids characterizes, for 10 points, what stage of mitosis preceded by metaphase.
In this stage, polar microtubules grow longer and push the spindle poles apart.  Simultaneously, kinetocore microtubules no longer fight each other as they move to opposing spindle poles, pulling attached chromosomes with them.  The separation of sister chromatids into independent daughter chromatids characterizes, for 10 points, what stage of mitosis preceded by metaphase.
In this stage, polar microtubules grow longer and push the spindle poles apart.  
anaphase