1. Mitosis and the Cell Cycle
Chapter 10
Mitosis and the Cell Cycle

2. Mitosis Song

3. Fun Facts DNA from one cell stretched out would be 2 m long
DNA from a baby would have 15 round trips from the sun to Pluto

4. Chromosomes Def. – DNA that is organized and packaged into structures
DNA is composed of hereditary units called genes

5. Chromosomes (cont.)(page 225)
Organized by super-coiling
They are coiled around a protein called a histone.
A DNA wrapped histone is then called a nucleosome.

8. Cell Cycle Cell cycle= the cell’s life cycle Made up of 3 parts
Interphase
Mitosis
Cytokinesis

9. Cell cycle continued Interphase
This is where the cell will spend most of its life
During this phase the cell is not dividing
3 phases
G1 (First gap phase)
S (Synthesis phase)
G2 (Second gap phase)

10. Interphase G1 Grows rapidly S Cell’s DNA is copied G2
Continues to grow and prepares to divide

12. Cell cycle continued
Cell Division- the following two steps is where the cell divides
Mitosis
Nucleus divides
Cytokinesis
Division of cytoplasm

13. Mitosis- 4 phases (pg 231) Prophase
Chromosomes become thick and visible
Nuclear membrane breaks down
Centrioles move to the poles
Spindle fibers form (attached to centrioles)

15. Mitosis Metaphase Nuclear membrane is completely gone
Chromosomes MEET in the middle of the cell
Spindle fibers attached to centromeres

17. Mitosis Anaphase Spindle fibers shorten
Sister chromatids (half an X) start to move to opposite sides of the cell (now a chromosome)
Ends when the chromosomes reach the poles

19. Mitosis
Telophase
A nuclear membrane forms around the chromosomes at each pole
Chromosomes uncoil and change back into chromatin form (spaghetti)
Spindle fibers break down and disappear

21. Cytokinesis- last part
Splitting of the cytoplasm
Different in plants and animals
Plants pg. 232
Have a cell plate form in the middle of the cell

22. Cytokinesis (cont.) Animals
Cell is pinched in half by a belt of protein threads
Balloon and string demo