Cell Division—Mitosis Notes
Cell Division — process by which
a cell divides into __________
• Why do cells need to divide?
1.Living things _______ by
producing _________, NOT
because each cell increases in
size
2._________ of damaged tissue
3.If cell gets too big, it _______
get enough _________ into
the cell and _______ out of
the cell
• The _________ cell is called the _________ cell;
2 ______ cells are called ___________ cells
• Before cell division occurs , the cell _________ (copies)
all of its ______, so each daughter cell gets complete set
of _______________ from parent cell
• Each daughter cell is ___________ like the parent cell –
_________ kind and number of _______________ as the
original cell
2
Daughter
Cells
Parent Cell
•Many organisms, especially
____________organisms, reproduce by means of
cell division – called ___________________ – Ex:
bacteria
DNA
• DNA is located in the ____________and controls all cell
_____________ including cell division
• Long and ____________ DNA in a ______________ cell
is called _______________
• ____________, ___________, short DNA in a
_______________cell is called _________________
Consists of 2 parts: ____________ and ______________
o 2 identical “sister”
chromatids attached at
an area in the middle
called a ____________
o When cells divide,
“sister”
________________
separate and 1 goes to
each new cell
•Chromatin to chromosomes illustration:
Chromatin
Duplicates
itself
Why does DNA need to change
from chromatin to chromosome?
Coils up into
chromosomes
More _________division
Chromosome number
• Every organism has its own ___________________ of
chromosomes
Examples: Human = ____ chromosomes or ________
Dog = ____ chromosomes or ___________
Goldfish = ____ chromosomes or _______
Lettuce = _____ chromosomes or _______
• All ____________ (body) cells in an organism have the
__________ kind and ____________ of chromosomes
Examples: Human = _______ chromosomes
Human skin cell = _____ chromosomes
Human heart cell = _____ chromosomes
Human muscle cell = ____ chromosomes
Fruit fly = ______chromosomes
Fruit fly skin cell = ___ chromosomes
Fruit fly heart cell = ___chromosomes
Fruit fly muscle cell =__chromosomes
Cell Cycle -- series of events cells go through as they
_______ and __________
•Cell ________, prepares for division, then _________
to form 2 ____________cells – each of which then
begins the cycle again
Interphase—period of cell _______ and ___________
•DNA __________ (copying) occurs during Interphase
•During Interphase the cell also ________, carries out
normal __________, replicates all other ___________
•The cell spends most of its life cycle in _____________
Mitosis – division of the _________ into 2 nuclei,
each with the same number of _______________
•Mitosis occurs in _____ the _________ (body) cells
So ____ new ____________
Why does mitosis occur? cell has ___________ with a
complete set of
_____________
• 4 phases of nuclear division (mitosis), directed
by the cell’s DNA (___________)
_________
_________—(Middle)
Anaphase—(Apart)
_____________—(Apart)
__________—(Two)
__________
 Chromosomes
_______ ____
 Nuclear envelope
____________
 _________ ______
form
______________—(Middle)
 Chromosomes line up
in __________ of cell
 Spindle fibers
_____________ to
chromosomes
_____________—(Apart)
 Chromosome
copies __________
 Spindle fibers pull
chromosomes to
_______________
______________—
(Two)
 Chromosomes
____________
 Nuclear envelopes
__________
 __________________
are formed
 Spindle fibers
________________
Cytokinesis — the ____________ of the rest of the
cell (_______________ and organelles) after the
nucleus divides
In _____________ cells the
cytoplasm pinches in
In _________ cells a cell plate
forms
•After mitosis and cytokinesis, the cell returns to
________________to continue to grow and
perform regular cell activities
Summary: Cell Cycle
Interphase
Mitosis (PMAT)
Cytokinesis
•When cells become old or damaged, they ______
and are replaced with __________ cells
Cell Division Control
•_______ controls _____cell
activities including cell
______________
•Some cells _________
their ability to _________
their rate of cell division –
the DNA of these cells has
become ___________ or
changed (mutated)
•These super-dividing cells
form masses called
____________
•_________ tumors are _____ cancerous – these
cells do not spread to other parts of the body
•_________ tumors are ___________ – these cells
break loose and can invade and _____________
in other parts of the body (called metastasis)
•Cancer is not just one
disease, but ______
diseases – over
_____ different types
of cancers
http://www.youtube.com/watch?v=wRrNjHYxP_o
http://www.bbc.co.uk/blogs/adamcurtis/2010/06/th
e_undead_henrietta_lacks_and.html
Phase
Chromosome
Appearance & Location
Important Events
Interphase
DNA copies itself; chromatin
DNA replication, cell grows
and replicates organelles
Chromosomes coil up
Nuclear envelope
disappears, spindle fibers
form
Chromosomes line up in
the middle
Spindle fibers connect to
chromosomes
Anaphase
Chromosome copies divide
and move apart
Telophase
Chromosomes uncoil back
into chromatin
Cytokinesis
Chromatin
Spindle fibers pull
chromosome copies apart
to opposite poles
Nuclear envelopes reform,
2 new nuclei are formed,
spindle fibers disappear
Division of the rest of the
cell: cytoplasm and
organelles
Prophase
Metaphase