Download The Cell Cycle:

The Cell Cycle:
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The life cycle of the cell as it grows up (matures) and prepared to divide.
Has three stages:
o Interphase
o Mitosis
o Cytokinesis
Interphase:
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The “growing up” phase of the cell.
Cell becomes full size.
It makes a second copy of its DNA
DNA is called chromatin (loose, tangly DNA = easy for the cell to “read”)
It makes copies of organelles
It is the longest stage of the cell cycle
Mitosis:
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Making a second nucleus.
Has four stages
o Prophase
o Metaphase
o Anaphase
o Telophase
Remember: ProMAT
Prophase
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“pro” means “in front of” / first step of mitosis
Chromatin (loose, tangled DNA) becomes coiled and compacted.
Coiled, rod-shaped DNA is called a chromosome.
The matching (two copies of) chromosomes (called sister chromatids) pair up and
are held together by a centromere.
The nuclear membrane dissolves/disappears.
Metaphase
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“meta” means “middle
Chromosomes line up along the center of the cell (the equator or metaphase plate)
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Spindle fibers form as a guide to direct one set of chromosomes to each side of
the parent cell. Centromeres attach to the spindle fibers.
Anaphase
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“ana” means “to back away”
Chromosomes pairs separate and begin to back away from each other so that
one complete set travels to each side of the parent cell.
Telophase
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“telo” means “at a distance”
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Chromosomes are now “at a distance” from each other with one complete set on
either side of the parent cell.
Parent cell stretches into a “figure 8” form and begins to pinch in at the center so
that two cells may form
New nuclear membranes form around the two sets of chromosomes (red in this
picture)
Cytokinesis
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The two daughter cells separate from one another.
In animal cells this separation happens when the cell membrane continues to
pinch in like a water balloon.
In plant cells (and other cells with a cell wall), a cell plate forms down the center
of the dividing cell. It contains material needed to build a dividing cell wall
between the daughter cells so that they can separate.
***This is a continual cycle that repeats over and over. Once a cell finishes cytokinesis, it
starts back at interphase again. ***