1. The Cell Cycle

2. Order of cell organization………
Cell  Tissue  Organ  Organ System  Organism
**Cells must divide and create many cells in order for this process to occur

3. The Cell Cycle  Interphase, Mitosis and Cytokinesis
Interphase (G1, S and G2)
G1 –
(Organelles Duplicate)
S – DNA synthesizes (also called duplicates or replicates)
G2 –
(Cell prepares to divide)

4. The Cell Cycle **Interphase  Organelles replicate, DNA synthesizes and cell prepares to divide ** Mitosis is Asexual Reproduction Divides Nucleus **Cytokinesis  Divides Cytoplasm

5. Interphase – Prepares for Mitosis
** Majority of time for a cell is in this phase
** Cell grows
** Organelles duplicated (G1)
**DNA synthesizes (S)
** Only chromatin (uncoiled chromosomes) visible

6. Chromosomes Duplicate In the S Phase of Interphase
Carriers of genes
Some genes carry the “instructions” for protein production
Remember, chromosomes are duplicated during the S phase of Interphase prior to mitosis!
You have 46 total chromosomes in the nucleus of most of your cells!!

7. **Nuclear Division Called Mitosis

8. **Prophase **Metaphase After Interphase **Anaphase **Telophase
**Four phases of mitosis (cell division) are:
**Prophase
**Metaphase
**Anaphase
**Telophase
**Recall Mitosis Divides the nucleus, Cytokinesis Divides the Cytoplasm

9. Prophase ** Duplicated chromosomes become visible
** A spindle, football shape structure that contains many fibers, moves to opposite poles

10. Metaphase
**Chromosomes line up in the MIDDLE of the cell ) its equator)
**Each chromatid is attached to a separate spindle fiber by its centromere (in the middle!!)

11. Anaphase ** Centromeres split pulling apart sister chromatids.
** Chromatids move to opposite poles

12. Telophase ** Chromosomes uncoil back into chromatin
Animal Cell
** Chromosomes uncoil back into chromatin
** Two nuclei appear
** In animals a cleavage furrow forms (plants have a cell plate)
** In plants a cell plate forms between the 2 cells

13. Cytokinesis – Division of Cytoplasm
** Two new identical daughter cells after

14. Mitosis at a Glance– Cell Division

15. Cytokinesis in an Animal Cell
ONLY in animal cells

16. Cytokinesis in a Plant Cell
Only in Plants
Only in Plants

17. Onion Root Tip – Can You Find the Stages of Mitosis

18. Mitosis in Real Time

19. Modeling Mitosis

20. Really Cool Animation

21. Cell Cycle in Prokaryotes (Bacteria)
**NO TRUE NUCLEUS!!! DNA replicates and the plasma membrane just pinches inward to form two new cells.