Cell Cycle
MITOSIS
7TH GRADE SCIENCE
TEACHER: DIEGO VALVERDE
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Cell division is necessary for any organism to grow
and, once it has fully developed, to maintain healthy
tissues.
There are two types of cell division, meiosis and
mitosis. Meiosis occurs in sexually reproducing
organisms like animals and plants. The process of
meiosis involves DNA being replicated and divided
into daughter cells that have half the number of
chromosomes of the parent cell. This is to allow for
two reproductive cells to join, thus creating new
life. Mitosis is the asexual reproduction of a cell,
occurs in a fully formed organism to replace old cells
or repair damaged tissue. The process of mitosis
results in the replication of identical cells.
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.
Animated Cell Cycle
http://www.cellsalive.com/mitosis.htm
• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase &
Cytokinesis
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Stage 1- Interphase
 Longest part of cell life
 Cell carries out normal activities
 DNA in long strands called chromatin
 Centrioles as a pair
Centrioles
Late Interphase
Chromatin doubles to form
chromosomes (# doubles)
• Other cell parts also double
• Editing of DNA to repair errors
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Centrioles
Nucleus
CELL
MEMBRANE
Cytoplasm
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Stage II- Mitosis
Phase # 1- Prophase
Chromosomes coil and become visible
• Centrioles (or poles) appear and begin to
move to opposite end of the cell. Spindle
fibers form between the poles.
• Nuclear membrane disappears.
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Centrioles
Sister chromatids
Spindle fibers
Animal Cell
Plant Cell
Spindle fibers
Centrioles
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Phase # 2- Metaphase
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Chromosomes line up in the
middle of the cell on the
spindle fibers.
Centrioles
Spindle fibers
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Phase # 3- Anaphase
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Chromatids (or halves 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
Phase # 4 - Telophase
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Chromatids finish separating.
Nuclear membrane reforms
Chromatids unwind and become
chromatin.
Nuclei
Chromatin
Nuclei
Animal Cell
Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
STAGE III - Cytokinesis
Cytoplasm and cell organelles
divide evenly
• Two new cells are formed
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Animal Cell Cycle -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
Plant Cell Cycle -- Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
1. Interphase
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase
6. Cytokinesis
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I Pick More Apples Than Chris
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https://www.youtube.com/watch?v=L61Gp_d7evo
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https://www.youtube.com/watch?v=lFzuw6ZWOGI
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https://www.youtube.com/watch?v=ZyXrtODhJEA
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https://www.youtube.com/watch?v=ZeW8HaCUtOQ