Mitosis
•a form of
asexual Reproduction
•
Mitosis is the process in which the
nucleus divides to form two new nuclei
(Click on Mitosis above for video)
2
2
How do little elephants grow up to be BIG
elephants?
Skin cancer - the abnormal growth of
skin cells - most often develops on skin
exposed to the sun.
Cell that reproduce by asexual
reproduction reproduce constantly.
Is found inside of the cell
 Every human body cell has 46
chromosomes (23 from mom, 23 from
dad)
 DNA is copied during interphase (before
mitosis starts)

The process of asexual
reproduction begins after a
sperm fertilizes an egg.
Both plants and animals use mitosis
 Some unicellular organisms use mitosis to
reproduce

Plant cells have chloroplast (for
photosynthesis)-they also have cell
walls
 Plant cells also have large vacuoles
to store water
 Animal cells have no chloroplast or
cell wall-contains small vacuoles if
any


Centrioles, spindle fibers, centromeres are
all temporary structures in the cell used for
mitosis
Centrioles move to the opposite ends of
the cell and attach to chromosomes by
spindle fibers
Animated Mitosis Cycle
http://www.cellsalive.com/mitosis.htm
Cell Division occurs in a series of stages,
or phases
• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase & Cytokinesis
Chromosomes are copied (# doubles)
• Chromosomes appear as threadlike coils
(chromatin) at the start, but each chromosome
and its copy(sister chromosome) change to sister
chromatids at end of this phase
•
Nucleus
CELL
MEMBRANE
Cytoplasm
Centromere-holds together the sister chromatids
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
•
•
Mitosis begins (cell begins to divide)
Centrioles (or poles) appear and begin to
move to opposite end of the cell.
Spindle fibers form between the poles.
Centrioles
Sister chromatids
Spindle fibers
Animal Cell
Plant Cell
Spindle fibers
Centrioles
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Chromatids (or pairs of chromosomes) attach
to the spindle fibers.
Centrioles
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Chromatids (or pairs of chromosomes)
separate and begin to move to opposite
ends of the cell.
Centrioles
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
•
•
Two new nuclei form.
Chromosomes appear as chromatin (threads
rather than rods).
Mitosis ends.
Nuclei
Chromatin
Nuclei
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
•
Cell membrane moves inward to create two
daughter cells – each with its own nucleus
with identical chromosomes.
Animal Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
Plant Mitosis -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
28
http://www.cellsalive.com/mitosis.htm