Describe the process of mitosis.

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Occurs  in  somatic/body  cells;  through  five  main  stages/phases:  Interphase/Resting  stage; intense  internal  activities  occur  in  the  cell  at  this  stage  in  preparation  for  the  division;  the activities  include;  replication  of  each  chromosome  to  multiply  genetic  material  to  retain chromosomal  number  in  daughter  cells;  chromosomes  appear  as  a  diffuse  tangle  of  threads (chromatin);  synthesis  of  new  cellular  organelles;  build-up  of  energy  stores  (ATP)  to  drive  the entire  cell  division  process;  Prophase;  chromosomes  become  visible;  as  they  shorten  and thicken  appearing  as  discrete  strands  (chromatids)  lying  parallel  to  each  other;  in  animal  cells, centrioles  separate  and  move  to  opposite  ends  (poles)  of  the  cell;  they  radiate  from  each  of  the ends  forming  spindle  fibres;  nuclear  membrane  begins  to  breakdown;  nucleolus  disappear; Metaphase;  chromosomes  migrate/move  to  the  centre  of  the  cell;  and  align  themselves  along the  equatorial  plane  of  the  spindle;  they  get  attached  to  the  chromosomes,  by  their  centromeres; nuclear  membrane  breaks  down    and  disappears;  spindle  fibres  lengthen;  and  attach  to  the centrioles  at  both  poles  forming  asters;  Anaphase;  chromatids  separate  at  the  centromere; shortening  of  the  spindle  fibres  occurs;  resulting  in  the  chromatids  migrating  to  opposite  poles of  the  cell;  spindle  apparatus  begins  to  disappear;  Telophase;  final  stage  where  chromatids reach  the  poles;  become  densely  packed  together  and  uncoil;  a  nuclear  membrane  forms  around each  mass/set  of  chromatids  (now  referred  to  as  chromosomes);  cytoplasm  divides  into  two (cytokinesis);  in  animal  cells,  the  cytoplasm  divides  by  constriction  of  the  cell  membrane; while  in  plant  cells,  a  cell  plate  forms  within  the  cytoplasm  and  grows  to  separate  the  cell  into two;  spindle  fibres  disappear  within  the  cytoplasm;  and  nucleoli  reappear  in    the  nuclei;  of  the two  daughter  cells  formed  at  the  end  of  telophase;  Max.
  20  mks 

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