THE 4 STAGES OF
START
Prophase
Metaphase
Telophase
Anaphase
Prophase
 The chromosomes coil.
 The nuclear membrane disintegrates.
 The spindle apparatus forms.
 The nucleolus disappears.
Each centrosome of an animal cell contains two
centrioles. Plant cells do not have centrioles but
they do form spindle fibers.
Photographs of Prophase
Animal cell (early prophase)
Plant (onion)
Metaphase
 The nuclear membrane disappears completely.
 In animal cells, the two pair of centrioles align at
opposite poles of the cell.
 Polar fibers continue to extend from the poles to the
center of the cell.
 Chromosomes move randomly until they attach to
polar fibers from both sides of their centromeres.
 Chromosomes align at the metaphase plate at right
angles to the spindle poles.
 Chromosomes are held at the metaphase plate by
the equal forces of the polar fibers pushing on the
centromeres of the chromosomes.
Photographs of Metaphase
Animal cell (whitefish)
Plant cell (onion)
Anaphase
 The paired centromeres in each distinct chromosome begin to
move apart.
 Once the paired sister chromatids separate from one another,
each is considered a "full" chromosome. They are referred to
as daughter chromosomes.
 Through the spindle apparatus, the daughter chromosomes
move to the poles at opposite ends of the cell.
 The daughter chromosomes migrate centromere first and the
kinetochore fibers become shorter as the chromosomes near
a pole.
 In preparation for telophase, the two cell poles also move
further apart during the course of anaphase. At the end of
anaphase, each pole contains a complete compilation of
chromosomes.
Photographs of Anaphase
Early Anaphase Plant Cell (onion)
Animal Anaphase
Late Anaphase Plant Cell (onion)
Telophase
 The polar fibers continue to lengthen.
 Nuclei begin to form at opposite poles.
 The nuclear envelopes of these nuclei are formed from remnant
pieces of the parent cell's nuclear envelope and from pieces of the
endomembrane system.
 Nucleoli (plural form of nucleolus) also reappear.
 Chromatin fibers of chromosomes uncoil.
 After these changes, telophase/mitosis is largely complete and the
genetic "contents" of one cell have been divided equally into two.
Photographs of Telophase
Early Telophase Plant Cell (onion)
Telophase Animal Cell (whitefish)
Late Telophase Plant Cell (onion)
Glossary
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b
Spindle Apparatus (spindle fibers)- A collection of microtubules attached
to a centromere during mitosis and meiosis that are responsible for the
movement of the chromosomes to opposite poles.
Centrosome- A small region of cytoplasm adjacent to the nucleus that
contains the centrioles and serves to organize microtubules.
Centromere- a region of a chromosome where it attaches to a spindle
fiber during mitosis and meiosis
Centriole- One of two cylindrical cellular structures that are composed
of nine triplet microtubules and form the asters during mitosis.
Polar fibers-microtubules that make up the spindle fibers
Chromatids- Either of the two daughter strands of a replicated
chromosome that are joined by a single centromere and separate during
cell division to become individual chromosomes.
Kinetochore- Either of two submicroscopic attachment points for
chromosomal microtubules, present on each centromere during the
process of cell division
Works Cited
 http://student.ccbcmd.edu/~gkaiser/biotutorials/
dna/mitosis/acprophaseB.html
 http://biology.about.com/od/mitosis/ss/mitosisst
ep_3.htm
 http://student.ccbcmd.edu/~gkaiser/biotutorials/
dna/mitosis/acmetaphase.html
 http://iknow.net/cell_div_education.html\
 http://www.cellsalive.com/mitosis.htm
 http://student.ccbcmd.edu/~gkaiser/biotutorials/
dna/mitosis/actelophase.html
 http://www.biologycorner.com/resources/cell_cy
cle.jpg