The Cell Cycle

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The Cell Cycle

• The Stages of Mitosis

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In the beginning
You all began life as a single cell.
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Then two, four, eight, sixteen
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And nine months later
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But how does this all happen?
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Mitosis

• The process that ensures each new cell has a
  nucleus with a complete set of
• instructions.

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4 Steps of Mitosis

• Prophase
• Metaphase
• Anaphase
• Telophase

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Mitosis Animation
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Prophase
Chromosomes condense and can be seen with a light
microscope. The nucleolus and nuclear membrane
disappear. Spindle fibers (animals only) begin
to form and attach to one side of each centromere
(middle of the chromosome).
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Metaphase
The tugging action of the spindle fibers pull the
double-stranded chromosomes into a line across
the centre of the cell.
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Anaphase
The spindle fibers begin to contract and shorten.
This pulls the centromere apart. The
double-stranded chromosome breaks into two single
strands and move to opposite ends of the cell.
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Telophase
One complete set of chromosomes is now at each
pole (end) of the cell. The spindle fibers
disappear and the nuclear membrane and nucleolus
form around each new set of chromosomes. The
cell is ready to divide into two new cells.