Cell CycleCell Division Mitosis and cytokinesis Mitosis Growth

Cell Cycle/Cell Division Mitosis and cytokinesis

Mitosis • Growth – Somatic (body) cells undergo mitosis for growth. • Maintenance – Somatic cells use mitosis to repair damage. • Asexual Reproduction – Mitosis is the process used by some organisms to reproduce (budding, etc…)

Steps to Mitosis • Interphase • Steps to Mitosis – – – Prophase Metaphase Anaphase Telophase Cytokinesis

Interphase • 1 - DNA replication • 2 - transcription and translation (normal cell growth)

Prophase • Chromatins condense • Nuclear envelope dissolves freeing DNA in the cell. Animal cells only: • Centrioles form spindle fibers

Metaphase • Metaphase Plate (chromosomes line up in the middle of the cell) • Highly organized so that both new cells will get exactly the same DNA • Spindle fibers completely attached to centromeres

Anaphase • Paired chromosomes are pulled to opposite sides • Each chromosome is an exact copy of one original chromosome. • Each end is considered a polar end.

Telophase • Chromatids end up at separate poles, spindle fibers begin to dissolve • Nuclear envelopes begins to form • Cell starts to pinch off through cytokinesis

Cytokinesis • Division of all the rest of cellular organelles into two identical daughter cells. Animal Cells: Actin forms around the center of the cell and contract pinching off two cells. Plants Cells: New cell plate created between the two cells.

Mitosis Animation • http: //www. biology. arizona. edu/cell_bio/tutorials/cell_cycle/cells 3. html