Centrioles migrate to opposite sides of cell. Spindle fibers run from the centromeres to the poles. Splitting of the centromeres marks the end of metaphase and the beginning of anaphase. Cytokinesis involves the formation of a cleavage furrow in animal cells and a cell plate in plant cells. Nuclear membrane reappears.
Chromosomes begin to uncoil and form chromatin.
You will arrest the onion cells in various stages of mitosis. Acetocarmine is used to stain the chromosomes. Be sure you can identify the regions shown in the diagrams on page 42 of the lab manual. Don't confuse mitosis and asexual reproduction. They are NOT the same thing.