Mitosis - Wayne County Public Schools

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Mitosis
By: Ann Benning
Asexual Reproduction
• Asexual Reproduction: One parent, the offspring is a clone
of the parent/organism because of no exchange of genetic
material
• Four types of Asexual Reproduction :
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–
–
–
Mitosis
Bidding
Binary Fission
Regeneration
• There is only 1 parent involved and the offspring is identical
(nothing is different) to the parent
What is Mitosis?
• Mitosis is a process where a single a single cell
divides resulting in two genetically identical cells
• Before Mitosis begins Interphase occurs
• Mitosis has 4 steps (PMAT)
–
–
–
–
Prophase
Metaphase
Anaphase
Telophase
• New cells are produced by the power of mitosis
Interphase
• Interphase has to happen before anything can happen in
mitosis
• Interphase has an appearance a normal cell
• Chromosomes are not visible at the time and are long, skinny
things called chromatins
– Chromatins are made of 40% DNA and 60% Protein
• DNA is replicated
• Interphase is important to the cell because it prepares the cell
for mitosis
Prophase (Pmat)
• Prophase is the first step in mitosis
• Prophase is when the chromosome’s replicates are visible
and they attach themselves to centrioles
• Centrioles then move to opposite ends of the cell
• The nucleolus disappears and the nuclear envelope breaks
down
• Prophase is important to the cell because it forms all the
needed things/items they need to split the cell like
– Spindle Fibers
Metaphase (pMat)
• Metaphase is the 2nd step in Mitosis
• During Metaphase, chromosomes line up around the
equator of the cell
• The spindle fibers attach themselves to centrioles
• Metaphase is important to the cell because it starts
to allow the cell to divide into two
Anaphase (pmAt)
• Anaphase is the 3rd step in Mitosis
• The centromeres split into 2
• Spindle Fibers pull centromeres to opposite poles(ends) of
the cell
• The chromosomes split into 2 chromatids
– These are also pulled to the opposite ends of the cell
• Anaphase is important to the cell because it pulls the
chromosomes to the “new cells”
Telophase (pmaT)
•
•
•
•
Telophase is the 4th step of Mitosis
Chromatids unravel and form chromatids
Centrioles replicate themselves
The nuclear membrane comes and reforms around the
chromosome
– To make the 2 “new cells”
• Telophase is important to the cell because allows the cell
to divide into 2 new cells
Cytokinesis
• Cytokinesis is a step of cell cycle but not a step
in Mitosis
• Cytokinesis is the physical division of
cytoplasm to daughter cells
Ways to Remember
•Mitosis
–PMAT
(Prophase, Metaphase, Anaphase and Telophase)
•Cell Cycle:
–IPMATC
(Interphase, Prophase, Metaphase, Anaphase, Telophase and Cytokinesis)
Quick Review #14
1. What step does the centrioles replicate themselves?
a. Telophase
b. Prophase
c. Anaphase
2. What step does the cell look the same like nothing
will happen or nothing has happened?
a. Prophase
b. Anaphase
c. Interphase
3. What step does centromeres get pulled to opposite
ends of the cell?
a. Anaphase
b. Cytokinesis
c. Metaphase
4. What step do centrioles move to opposite ends of
the cell?
a. Metaphase b. Prophase
c. Telophase
Quick Review #2
5. How many parents does asexual reproduction need?
a. 10
b. 1
c. 2
6. When does the cell become 2 “new cells”?
a. Cytokinesis
b. Prophase
c. Telopahse
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