L.S.2 N.S. #4
Cell Division Notes
Why do cells undergo Cell Division?
_____To be able to split and make a new cell
_______________
Three types of Cell Division
A) __Binary Fission
_
B) ___Mitosis___________
C) ____Meiosis__________
A) Binary Fission- the ____simplest__________ form of cell division which
the cell splits into 2 equal parts_________
- Occurs in prokaryotic cells
and other one celled organisms
-Daughter cells are approximately
equal size.
- Purpose is to create a new organisms
for unicellular organisms
B) Mitosis- type of cell reproduction when the parent
cell splits into two identical daughter cells.
- Occurs in body cells (somatic cells)
- Purpose is to grow or _repair _
cells for multi-cellular organisms.
- Produces two identical daughter cells
(same DNA and number of chromosomes as the parent)
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C) Meiosis- type of cell reproduction which produces cells that have
___half___ the amount of _____DNA_____ as the parent.
-Occurs only in ___sex ___ _____cells________
(gametes)
- Purpose is to ____half___ the amount of
chromosomes to create ____4____ daughter cells
- Each daughter cell has half the amount of
___chromosomes____ as the parent, which later
can be united for an organism to undergo
___sexual __ ______reproduction____
Cell Cycle: Three phases for the cell cycle
_____Interphase______
Stage 1
____M-Phase_____
Stage 2
____Cytokinesis_______
Stage 3
Stage 1: ____Interphase__________- first stage of the cell cycle which
_____chromosomes_____ and other cell
materials are ____copied___.
-Cell is doing all the “____prep____”
work to divide.
-DNA ___replicates___
(makes a copy)
- ____Nucleus is visible__________
-_____Centrioles pair______________
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Stage 2: ____M-Phase____________ the cell is going through the actual
“phases” of mitosis or meiosis
The 4 phases of mitosis
Phase 1: ______Prophase_______
Phase 2: _______Metaphase______
Phase 3: _______Anaphase_______
Phase 4: _______Telophase________
Phase 1: ______Prophase________
- ___Nuclear__ ____Membrane__ starts
to disappear
- Chromosomes become _____visible____
- __Centrioles___ begin to separate and
____spindle__ ____fibers___ begin to form
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Phase 2: ______Metaphase___________
- “Meta” think ____middle_______
- Chromosomes line up in the
____middle_______ of the cell
- ___Centrioles_____ move to opposite poles of
the cell
-___Spindle fibers form_________
Phase 3: ____Anaphase_______________
- “Ana” think _____away_________
- Chromosomes start to ___pull___
___away____ toward opposite poles of the
cell.
- Each side of the cell has the __original___
number of chromosomes.
Phase 4: ______Telophase_______
-__Nuclear___ ____Membrane___
begins to form around new set of
chromosomes.
- Spindle fibers disappear
- Cell membrane “__pinches____ __in___”
beginning to form ___2___ daughter cells
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Stage 3: _____Cytokinesis______- last stage of the cell cycle
- ____Cytokinesis__ - division of
the cytoplasm.
- Forms __2__ ______daughter____
_____cells____
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Meiosis has __2__ rounds of cell division
Mitosis
Meiosis
- Produces __2__ daughter cells
- Produces _____4_____ daughter
that are ___identical__ to the
that have __half____ the DNA of
parent
parent
- __1 round of cell division
- ____2____ rounds of cell division
- Used for __growth__ and
- Used to make ___gametes _ for
___repair____
sexual reproduction