Mitosis Notes


  1.  Introduction Slide
Mitosis- The gradual, continuous process in which the nucleus divides. A second set of chromosomes is formed inside the cell.


When the cell splits and produces two new cells, each set of chromosomes goes to a new cell.



Phases of Mitosis






Nucleus is clearly seen
Chromosomes make copies of themselves.






Chromosomes become visible
Membrane around nucleus begins to disappear.





Chromosome pairs line up along the middle of the cell.







Chromosome pairs split apart and begin to move to opposite sides of the cell.










Nuclear membrane forms around each set of chromosomes
Each new nucleus has the same number of chromosomes as the original cell
Cytoplasm divides
Two new cells are formed




The nuclear membrane breaks down during prophase because the nucleus is preparing to divide.  


The nuclear membrane forms during telophase because the nucleus has divided and the membrane helps filter what reaches the nucleus of each new cell.  


Why is each stage (phase) necessary for mitosis to occur?  Each stage is a step in the process, if one does not occur mitosis will not happen.