what must occur before mitosis takes place
When a new cell is created, it must have the same library of genetic information all other cells in the body have access to. Because all the material in the new cell must come from the first cell, the original cell must make a copy of its DNA before completing the process of mitosis. These two sets of DNA only exist for as long as it takes the cell to undergo mitosis, which can be anywhere from 30 to 90 minutes in certain human cells.