1. 10.1 Cell Growth
Living things grow because it produces more and more cells.
Are the cells of an adult larger than the cells of a baby?

2. NO!!! Adults just have more cells than babies do.

3. Limits to Cell Growth Volume increases faster than surface area
The larger a cell becomes, there are more demands put on that cell. “DNA overload.”
Nutrients and waste have a hard time going in and out of the cell.
Hammond population and highways

4. Ratio of Volume to Surface Area
Surface area= (length x width x 6) cm2
Volume= (length x width x height) cm3
Ratio of volume S.A. to Volume= SA/ Volume

5. What happens when a cells gets too large?
Cell division- process whereby the cells divide into two daughter cells
Before the cell divides all the DNA is copied.
Each new daughter cells gets its own “genetic library” they each get all the DNA.

6. 10.2 Cell Division
Process in which the cell divides into two daughter cells. Each has the same exact information as the original cell.
Before cell division occurs the cell must replicate or copy all its DNA.
Solves the problem of DNA overload by dividing (reduces the cell’s volume)
Allows efficient exchange of materials with the environment.

7. Chromosomes
Structures found in the nucleus of a cell that contain genetic information.
Human cells have 46 chromosomes
23 chromosomes from mom
23 chromosomes from dad

8. Make up of a chromosome
A chromosome is composed of two identical chromatids attached by a centromere. Each chromatid is made up of tightly wound DNA wrapped around histones. .
                                                                                                           

9. Chromosomes DNA coils around a special protein called a HISTONE.
DNA and HISTONE make
up NUCLEOSOMES.

10. Cell Cycle
A cell grows, prepares for division, and divides to form two daughter cells…each of which repeat the cycle again.
From One mitosis to the next mitosis
Interphase, Cell division (mitosis), cytokinesis

11. Interphase G1=cell growth S phase= DNA is replicated
G2=cell prepares for mitosis
Kind of like intermission…can’t really see this happening, but happens behind the scene.

12. Interphase

13. Mitosis Process in which the nucleus of a cell divides.
Divided into four phases
Prophase-1st, longest phase. Chromatin condenses and chromosomes become visible.
Metaphase-2nd phase (shortest) chromosomes line up at center of cell
Anaphase-3rd phase chromatids split and separate to opposite poles
Telophase-4th phase. Almost two new cells, but not completely separated.

14. Mitosis

15. Prophase

16. Metaphase

17. Anaphase

18. Telophase

19. Cytokinesis
The cytoplasm pinches in half. Each daughter cell has an identical set of duplicate chromosomes.

20. Fine TUNING what you’ve learned.

21. 10.3 Regulating the Cell Cycle
Cyclin Protein Regulators- regulate the timing of the cell cycle.
Internal Regulators- make sure that mitosis has waited for chromosomes to replicate all the DNA.
External Regulators- speed up or slow down mitosis.

22. Cancer Uncontrolled cell growth is called cancer
Most healthy cells will stop dividing when they come into contact with one another.
Cancer cells do not stop when touch another cell. Grows until the nutrient supply is gone.

23. Cancer

24. What do cells do incase of injury?
Cells rush to the cite of the wound and rapidly divide.
They start to slow down when they get close to each other.
When do they stop?
When they touch one another…
At this time…you most likely have a scab.
On that note…we are done with this chapter. 