Identify the point in mitosis at which separase cleaves the protein complex that holds sister chromatid pairs together. In normal cells

In the transition of metaphase to anaphase, the cohesin complex is cleaved by the separase enzyme in a process dependent on the activation of specific proteins that trigger posttranslational modifications (i.e., protein degradation by ubiquitination). This process of cleavage enables the sister chromatids to separate and move to opposite sides of the cell

a physical change is being made.