Post on 18-Nov-2014
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How do little elephants grow up to be BIG elephants?
G2: Cell double-checks to make
sure DNA is replicated and
cell has enough organelles for the upcoming
split
G1: Cell grows in size.
S: Cell makes identical copy
of its DNA
M: mitosis (Cell divides)
What are the three phases of Interphase?
What happens during S phase? What happens during G1 phase? What happens during M phase? What happens during G2 phase?
Animated Mitosis Cyclehttp://www.cellsalive.com/mitosis.htm
• Interphase
• Prophase
• Metaphase
• Anaphase
• Telophase & Cytokinesishttp://highered.mcgraw-hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120073/bio14.swf::Mitosis%20and%20Cytokinesis
What is binary fission?
Why does the DNA need to move to either side of the cell before the cell divides?
• Chromosomes are copied (# doubles)
• Chromosomes (DNA) appear as threadlike spaghetti called chromatin
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
• Nucleus starts to disappear.
• Chromatin coils to become chromosomes.
• Centrioles (or poles) appear and begin to move to opposite end
of the cell. • Spindle fibers form
between the poles.
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Spindle fibers
Centrioles
• Chromatids (a pair of identical chromosomes) are dragged to middle of cell along the metaphase plate.
Centromere
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
• Chromatids (or pairs of identical chromosomes) separate and begin to move to opposite ends of the cell.
Sister chromatids
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
What are the steps of mitosis?
What is the spaghetti –like DNA called?
What is the coiled, bundled DNA called?
• Two new nuclei form. • Chromosomes unwind
into chromatin (threads rather than rods).
• Mitosis ends.
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 -- ReviewInterphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
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- Cell Division
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http://www.cellsalive.com/mitosis.htm