Mitosis Emile, Amanda, Jocelyn

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Emile Mirzoevs
Amanda Sabol
Jocelyn Sickler
 There
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are four stages of mitosis:
Prophase
Metaphase
Anaphase
Telophase
Photograph of a
Plant Cell – Click
Above
Photograph of a
Animal Cell –
Click Above
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Chromatin fibers become more tightly coiled and condense
into chromosomes that can be observed under a light
microscope.
Each duplicated chromosome appears as 2 identical sister
chromatids joined together.
The mitotic spindle begins to form. It is composed of
centrosomes and the microtubules that extend from them.
The centrosomes begin to move away from each other,
propelled by the microtubules.
Nuclear envelope fragments and the microtubules of the
spindle invade the nuclear area and interact with the
chromosomes. These extend toward the middle of the cell.
Each of the 2 chromatids of a chromosome now have a
kinetochore; a specialized protein structure located at the
centromere.
The microtubules attach to the kinetochore and jerk the
chromosome back and forth.
Largest stage of mitosis; lasts 20 minutes
 Centrosomes are now at opposite ends of a cell.
 Centrosomes convene at the metaphase plate,
an imaginary plane that is equidistant between
the spindle’s 2 poles. The chromosome’s
centromeres lie on the metaphase plate.
 For each chromosome, the kinetochores of the
sister chromatids are attached to kinetochore
microtubules coming from opposite poles.
 The entire apparatus of microtubules is called
the spindle because of its shape.

 Shortest
stage of mitosis; only lasts a few
minutes
 Begins when the 2 sister chromatids of each
pair suddenly part. Each chromatid thus
becomes a full-fledged chromosome.
 The two liberated chromosomes begin
moving toward opposite ends of the cell, as
their kinetochore microtubules shorten.
 Cell elongates as the nonkinetochore
microtubules lengthen.
 Two
daughter nuclei begin to form in the
cell.
 Nuclear envelope arise from the fragments of
the other parent cell’s nuclear envelope and
other portions of the endomembrane system.
 Chromosomes become less condensed.
 Cytokinesis divides the cytoplasm into two.
 Photograph
 Photograph
http://img.sparknotes.com/figures/D/d756b5b7
3abe2974f3521a828791899f/prophase.gif
 http://img.sparknotes.com/figures/D/d756b5b7
3abe2974f3521a828791899f/metaphase.gif
 http://withfriendship.com/images/h/35682/Ana
phase-picture.gif
 http://img.sparknotes.com/figures/D/d756b5b7
3abe2974f3521a828791899f/telophase.gif
 http://faculty.cbu.ca/cglogowski/BIOL%20101%2
0IMAGES/PlantCellMitosis_CL.jpg
http://waynesword.palomar.edu/images/plmito
3.jpg
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