Download Cell Cycle and Mitosis Notes ppt

MITOSIS
Why do cells reproduce?
How do cells reproduce?
What controls cell division?
What is the relationship between
mitosis and tumors?
Figure 12.3 Chromosome duplication and distribution during mitosis
Why do cells need to divide?
Some organisms divide in order to reproduce
(asexual reproduction)
• Organisms like humans
rely upon cell division in
order to grow, and to
replace old or damaged
cells
•
Mitosis Vocabulary
1. Mitosis - the first stage of cell division
when the nucleus divides
2. Cytokinesis – the second stage of cell
division, when the cytoplasm divide
3. Parent cell - the cell that is dividing
4. Daughter cells- the two new cells that form
from mitosis
Mitosis Vocabulary
5. Centriole - a small structure located near
the nucleus; it creates the spindle (in animal
cells only)
6. Spindle - a fibrous, oval-shaped structure
formed by the centrioles during mitosis
7. Nucleus - where DNA
is found in a
eukaryotic cell
Mitosis Vocabulary
8. Chromosomes (DNA threads) – genetic
material within the cell that controls the
cell’s activities.
9. Chromatids – sister strands of a replicated
chromosome attached at the centromere.
10.Centromere - the area (near
the middle) where sister
chromatids are attached to
each other.
G0
Cell Cycle
Prophase
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Longest phase
Replicated chromosomes become shorter and
thicker (condensed)
Nuclear membrane disappears
Centrioles begin to separate
The spindle (tiny threads) forms between the
centrioles
Prophase
Metaphase
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(line up in Middle)
Shortest phase
Centrioles finish separating and the spindle is
completely formed
The replicated chromosomes line up SINGLE
FILE in the middle of the cell
Metaphase
Anaphase
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(sister chromatids pull Apart)
Sister chromatids separate
One set moves to each end or pole
Ends when chromosomes stop moving
Anaphase
Telophase
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(makes Two new cells)
The nuclear membrane reforms around
each nucleus
The spindle (tiny threads) disappears
Each centriole is located outside of each
new nucleus
Chromosomes become longer and thinner
and then disappear
One cell separates into two identical cells
(cytokinesis)
Telophase
Cytokinesis
Occurs at the same time as telophase
• The cell membrane pinches inward in most
animal cells
•
Mitosis in Plant Cells
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Plants have no centriole, but the spindle
still develops
Plant cell cytoplasm separates into two
parts by the formation of a cell plate.
This becomes the cell wall of the new
plant cells.
See what you know!
The following are different stages
of mitosis. See if you can identify
what stage the cell is in.
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