Cell Division—Mitosis Notes
Cell Division — process by which a cell divides into ____________________
Why do cells need to divide?
Living things__________ by producing __________________________, NOT because each cell increases in
size___________________ of damaged tissue
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
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 ____________________
2 identical “sister”
chromatids attached at an area in the middle called a ______________________
When cells divide, “sister” _____________________ separate and 1 goes to each new cell
Why does DNA need to change from chromatin to chromosome?
More _____________________ division
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
Why does mitosis occur?
So ___________ new __________________ cell has _______________ with a complete set of
__________________
4 phases of nuclear division (mitosis), directed by the cell’s DNA (____________)
1. Prophase
Chromosomes __________________
Nuclear envelope ___________________
________________________ form
2. Metaphase—(Middle)
a. Chromosomes line up in _____________________ of cell
b. Spindle fibers ________________ to chromosomes
3. Anaphase—(Apart)
a. Chromosome copies ______________
b. Spindle fibers pull chromosomes to ___________________________
4. Telophase—(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
___________________ ________________________ ______________________
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 ______________________________ – the
DNA of these cells has become ____________________or changed (________________)
These ______________________________ cells form masses called _____________________
____________________ tumors are ___________________ – these cells _______________________ to other
parts of the body
_____________________ tumors are _________________________ – these cells break loose and can invade
and _________________________________ in other parts of the body (called ______________)
Cancer is not just one disease, but ____________________________ – over _______________________ types
of cancers
Phase
Interphase
Prophase
Metaphase
Anaphase
Telophase
Cytokinesis
Chromosome Appearance & Location
Important Events