CELL DIVISION

 When cell divides forming 2 new cells  Prokaryotic cells  Called Binary Fission  Split into 2 parts  Eukaryotic cells  Called Mitosis  Daughter cells form that are identical to parent

CHROMOSOMES  Chromosome  Threadlike structure made of DNA and protein  Different number depending on species  Example: fruit flies- 8 chromosomes  Humans: 46 chromosomes (23 pairs)  Chromatid- 2 copies of same chromosome  Centromere- holds chromatids together

STAGES OF MITOSIS  Interphase  Prophase  Metaphase (middle)  Anaphase (away)  Telophase  Cytokinesis

INTERPHASE  Where cell is most of the time  DNA copies itself (doubles)  Long strands of DNA  Can’t be clearly seen

PROPHASE  DNA shortens and can be seen  Nuclear membrane disappears  Spindle fibers appear (come from centrioles)  Group of fibers that guide movement of chromosomes

METAPHASE  Chromosomes continue to shorten and thicken  Chromosomes line up in the middle of the cell

ANAPHASE  Spindle fibers pull apart the doubled chromosomes  Separates and forms 2 single chromosomes  Move to opposite sides

TELOPHASE  Spindle fibers disappear  Nuclear membrane forms around each set of chromosomes  One cell pinches together into 2 new cells  Cytokinesis