Why would you to expect genetic differences between cells to arise from meiosis and not from mitosis?

you will expect MORE genetic differences in meiosis....(you can always get genetic differences due to mutation in both processes).....but anyway, the goal of mitosis is to make an exact replica of the cell....the goal of meiosis is to make sperm/egg cells which will be half of the material used to make a typical body cell (so that when the halves join, they will make one fully functional cell). During one stage of meiosis, there is a process called "crossing over" in which the chromosomes will exchange some genetic material. This helps to ensure that the sperm/egg cell will be somewhat different from the parent cells