2. Cell Cycle 3 Steps Interphase cell growth and development
Longest phase
Mitosis
cell reproduction creating 2 new nuclei
Cytokinesis
cell reproduction finishes
creating 2 new cells (DAUGHTER)

4. Importance of Cell Division
Some cells get old and wear out
New cells formed by the cell cycle replace old cells before they die
For example: every human is shedding old skin cells. We loose about 40,000 cells every minute.
Cells lining the stomach are replaced every week because your stomach is so acidic
New cells formed by the cell cycle replace old cells before the cell dies.

5. Vocabulary Preview Cell Cycle Interphase Mitosis Cytokinesis
Prophase
Metaphase
Anaphase
Telephase
Cytokinesis
Homologous Chromosome
Daughter Cell
Sister Chromatid
Centromere
Cell Plate

6. Length of a Cell Cycle
The length of a cell cycle is different for each type of organism and every different type of cell (skin, heart, lung, etc…)
When organisms are young and growing, the cell cycle repeats more quickly.
An example: A zebra fish grows from 1 cell to 256 cells in 15 minutes

7. Preview Cell Division
Enlarge Screen for a bigger view

8. Phases of the Cell Cycle

9. RESULTS OF CELL DIVISION
After Mitosis and Cell Division, the original cell, called the parent cell NO LONGER EXISTS
After the cell cycle (at the end of cytokinesis) 2 new identical cells (called Daughter cells) are created. They are genetically identical to the parent cell.
Think Write Pair Share: What happened to the original parent cell?
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10. Interphase First Phase of the Cell Cycle
Chromosomes (which is another name for the DNA) in the nucleus are like a bunch of spaghetti noodles.
For each chromosome there is an identical chromosome. This identical pair is called homologous chromosomes.
Humans have 23 pairs of homologous chromosomes.

11. Phase in Interphase Interphase has three phases G1, S, and G2. G1
Cells grow
perform cell functions (do their job) S
DNA is copied G2
perform cell functions (do their job),
all organelles are copied

13. Mitosis 2nd part of the Cell Cycle
Mitosis is a continuous process.
PMAT
It is made up of 4 phases
Prophase
Metaphase
Anaphase
Telophase
PREVIEW:

14. Prophase The first phase of mitosis is Prophase.
1) Chromosomes (DNA) twist (condense) into tight coils
2) Nucleus breaks apart

15. Metaphase
During Metaphase, all the chromosomes that are attached to the fibers move to the middle of the cell.
The pairs line up end to end, across the center of the cell.
“Meet in the middle”

16. Anaphase
During Anaphase, The chromosomes are pulled apart making 2 sister chromatids.
The sister chromatids are pulled to opposite sides of the cell

17. Telophase
During Telophase, a new nuclear membrane forms around the separated chromatids making 2 identical nuclei in 1 cell.

21. Cytokinesis

22. Cytokinesis

23. Viewing Cell Division
Cell Cycle, Animal Mitosis, & Plant Mitosis
Mitosis:
Plant Cell Mitosis:
Microscopic:
Hand Drawn:
Living Cell-Time lapse photography:

24. Writing to Learn
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