1. Cell Growth and Revision
CHAPTER 5
Cell Growth and Revision

2. Why do cells reproduce? GROWTH REPAIR ________________________

3. Life Spans of Body Cells ______________________
Stomach lining cells: 2 days
Life Spans of
Body Cells
______________________
Platelets: 10 days
Skin Cells: 20 days
______________________
Red Blood Cells: 120 days
______________________
______________________
Brain cells: years
Intestinal lining cells: 3 days
______________________

4. Chromosomes DNA plus proteins is called chromatin.
chromatid
telomere
centromere
One half of a duplicated chromosome is a chromatid.
Sister chromatids are held together at the centromere.
Telomeres protect DNA and do not include genes.
Condensed, duplicated chromosome
Condensed, duplicated chromosome

5. The Cell Cycle
The four stages of the cell cycle are gap 1, synthesis, gap 2, and mitosis.
1) Gap 1 (G1): cell growth and normal functions
2) DNA synthesis (S): copies DNA
3) Gap 2 (G2): additional growth
4) Mitosis (M): includes division of the cell nucleus (mitosis) and division of the cell cytoplasm (cytokinesis)
Mitosis occurs only if the cell is large enough and the DNA undamaged.

6. Mitosis Interphase prepares the cell to divide.
Mitosis and cytokinesis produce two genetically identical daughter cells.
Parent cell
centrioles
spindle fibers
centrosome
nucleus with
DNA
Interphase prepares the cell to divide.
During interphase, the DNA is duplicated.

7. Steps of Mitosis Prophase Metaphase Anaphase Telophase PMAT
_______________________________________
PMAT

8. PROPHASE Sister Chromatids Nuclear Membrane Centrioles Fibers
Shorten and Thicken
Begins to break down
Move apart from one another
Form between centrioles

9. METAPHASE Sister Chromatids Nuclear Membrane Centrioles Fibers
Become attached to the fibers. Are pulled to middle of cell
Are stretched between the two ends of cell
Remains dissolved
Move to opposite ends of cells

10. ANAPHASE Sister Chromatids Nuclear Membrane Centrioles Fibers
Pulled apart by fibers.
Each chromatid is separate from its “sister”
Still at cell’s poles;
Pull each chromatid toward opposite ends of cell
Remains dissolved

11. TELOPHASE Sister Chromatids Nuclear Membrane Cell Membrane Fibers
Each end of cell has a complete set of chromosomes.
Begins to pinch, forming two new cells
Begin to disappear
Begins to reform

12. Mitosis Cytokinesis differs in animal and plant cells.
In animal cells, the membrane pinches closed.
In plant cells, a cell plate forms.

13. Result in two IDENTICAL daughter cells
The Point of Mitosis
Result in two IDENTICAL daughter cells
Each cell will have the SAME number
of chromosomes as the original cell.
Each cell will have the SAME job as the original cell.

14. Understanding Mitosis
Starting with prophase, draw a cell undergoing mitosis.
Your original cell has 8 chromosomes.
Make sure to include the cell membrane,
nuclear membrane, chromosome,
centrioles, and fibers.
PROPHASE
ANAPHASE
METAPHASE
TELOPHASE

15. INTERPHASE PROPHASE METAPHASE ANAPHASE TELOPHASE Cell’s Life Cycle:
Mitosis:
Prophase
Metaphase
Anaphase
Telophase
INTERPHASE
____________________________________________________________
PROPHASE
METAPHASE
ANAPHASE
TELOPHASE
____________________________________________________________
____________________________________________________________
____________________________________________________________
____________________________________________________________

16. Plant Mitosis

17. Plant Cell vs. Animal Cell
MITOSIS
Plant Cell vs. Animal Cell
The process is VERY SIMILAR in each type of cell.
There are only 2 differences:
Plant cells do not have centrioles
A cell wall is laid down at the end of the cell division.

18. Can You Put These Cells In The Correct Sequence Of Mitosis?
??So What Is This??
3. Anaphase
2. Metaphase
___________________
___________________
___________________
??So What Is This??
1. Prophase
4. Telophase
___________________
___________________
___________________

19. Mitosis is only a small part of a cell's
"LIFE CYCLE"
_____________________________
(Just like you; You will only spend a short time of your life actually reproducing!")
At least...LET'S HOPE SO!
INTERPHASE
The cell spends most of its life in
_____________________________
(The phase IN-BETWEEN mitosis)
Life Cycle Animation

20. Can You Put These Cells In The Correct Sequence Of Mitosis?
3. Anaphase
Interphase
2. Metaphase
___________________
___________________
___________________
1. Prophase
4. Telophase
Interphase
___________________
___________________
___________________

21. An organism's cells are in different parts of their life's cycle.
Rates of Mitosis
An organism's cells are in different parts of their life's cycle.
Can you identify the phases of this plant's cells?
__________
______________
__________
______________
______________

22. Changes in the Rate of Mitosis
Changes often occur in the growth rate of cells.
Faster Rate of Mitosis:
CANCER
_______________________
Slower Rate of Mitosis:
AGING
_______________________

23. Cancer Cell division is uncontrolled in cancer.
Cancer cells form disorganized clumps called tumors.
Benign tumors remain clustered and can be removed.
Malignant tumors metastasize, or break away, and can form more tumors.
cancer cell
bloodstream
normal cell

24. Cancer Cancer cells do not carry out necessary functions.
Cancer cells come from normal cells with damage to genes involved in cell-cycle regulation.

25. Cancer Carcinogens are substances known to promote cancer.
Standard cancer treatments typically kill both cancerous and healthy cells.

26. Chemicals used on household items
CANCER CAUSERS
SOME VIRUSES
RADIATION
1._________________________
2._________________________
Sun
X-Rays
______________
______________
CHEMICALS
3._________________________
Chemicals used on household items
and/or pesticides
Nuclear Wastes
Drugs
__________________ __________________ ____________________

27. CHROMOSOMES OF ORGANISMS
“GUESSTIMATE”
ACTUAL CHROMOSOME #
CAT
DOG
CHIMPANZEE
EARTHWORM
GOLDFISH
CARROT
LETTUCE
ONION
CHICKEN
GUINEA PIG
HUMAN
MOSQUITO
PEA
PENICILLIN
CORN
FROG 32 78 48 36 94 18 18 16 78 64 46 6 14
1-4 20 26

28. Chromosome Comparisons
If an organism has more chromosomes,
does that mean it is smarter? NO
If an organism has more chromosomes,
does that mean it is larger? NO
If an organism has more chromosomes,
does that mean it is more complex or evolved? NO

29. Stem cells are unique body cells.
Stem cells have the ability to
divide and renew themselves
remain undifferentiated in form
develop into a variety of specialized cell types

30. Stem Cells Stem cells are classified into three types.
totipotent, or growing into any other cell type
pluripotent, or growing into any cell type but a totipotent cell
multipotent, or growing into cells of a closely related cell family

31. Stem Cells Stem cells come from adults and embryos.
Adult stem cells can be hard to isolate and grow.
The use of adult stem cells may prevent transplant rejection.
The use of embryonic stem cells raises ethical issues
Embryonic stem cells are pluripotent and can be grown indefinitely in culture.
First, an egg is fertilized by a sperm cell in a petri dish. The egg divides, forming an inner cell mass. These cells are then removed and grown with nutrients. Scientists try to control how the cells specialize by adding or removing certain molecules.

32. Stem Cells
The use of stem cells offers many currently realized and potential benefits.
Stem cells are used to treat leukemia and lymphoma.
Stem cells may cure disease or replace damaged organs.
Stem cells may revolutionize the drug development process.