Download Cell Cycle/Cell Division

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/cells3.html