Post on 09-Feb-2016
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Interphase
• This cell shows how all cells look before mitosis.
• Interphase is a phase of the cell cycle, but technically, NOT a stage of mitosis.
Prophase• The nuclear membrane breaks down.• The chromosomes shorten and
thicken. • The other structures important for
mitosis are also forming (ex. the centrioles).
Metaphase
*The chromosomes are pulled to the cell's equator by the spindle fibers.
*The chromosomes MEET IN THE MIDDLE
Detail…• Here's the confusing part -
When the individual chromatids (½ of the "X") are separated from the chromosome (the "X"),
• They are now, each referred to as a full chromosome.
• In other words, the chromosome, composed of two chromatids, separates into the separate chromatids, which are then renamed chromosomes, even though they were only one half of a chromosome only moments before! - Whew!
Anaphase
• The newly formed chromosomes are pulled by the spindle fibers toward opposite poles of the cell.
Telophase
• The chromosomes stop moving.• The spindle fibers break down. • The membrane of the cell pinches
creating two separate cells. • The nuclear membrane reforms.• The nucleolus reappears.
Very Last Part…Cytokinesis
• This is when the two new cells completely divide.
• Plant and Animal cells do this differently!
Animal Cell• A ring (contractile ring) tightens and
tightens until the two new cells pinch apart.
Cleavage Furrow