1. The Life Cycle of the Cell and Mitosis
Sections 8.1, 8.2, 8.6, 8.7, 8.8

2. The Life Cycle of the Cell

3. G1 Stage G1 = Growth or Gap Cell Increases in Size
Cell Performs its role, job or function

4. S Phase S = Synthesis Cell Replicates [copies] its DNA
Cell continues to perform its job

5. G2 Stage Cell continues to perform its job
Cell prepares all other material necessary for the Mitosis [Cell Division]

6. Interphase G1 + S + G2 = Interphase Phase / Stage between Divisions
Not Technically part of Mitosis but included in discussion
PLANT OR ANIMAL

7. INTERPHASE

8. Mitosis
Definition: Cell Division Producing Two Genetically Identical Daughter Cells
Two Major Events
Karyokinesis: Division of the Nucleus
Cytokinesis: Division of the rest of the Cell
Divided into Four Stages
Divisions made on morphology [physical appearance] and cellular activity [what the cell is doing]

9. Prophase Observable Events:
DNA condenses from Chromatin to Chromosome form.
The Nucleolus “Disappears”.
The Nuclear Envelope “Disappears”
Mitotic Spindle Apparatus Forms
Prophase Congression occurs
Animal Cells Only: Centrioles Migrate to opposite ends of cell

10. Prophase [continued] Chromatin v. Chromosome DNA
Long, Thin, Useable v. Short, Thick and Inaccessible
Nucleolus “Disappears” as DNA condenses
Nuclear Envelope Stored in Rough E.R.
Mitotic Spindles:
Protein Strands [microtubules] used to separate chromosomes; attach to the Centromere
Prophase Congression:
Movement of the Chromosomes to Plane of Division

11. Prophase [continued]

12. PROPHASE

13. Metaphase
Observable Event: Centromere of the Chromosomes line up at the Plane of Division [usually the middle of the Cell]

14. Metaphase [continued]
Centromere:
Part of the Double Chromosome to which the Mitotic Spindles Attach
Chromatid:
one half of a Doubled Chromosome
NOT used when Chromosome is Single [prior to the S Phase or After Anaphase]

15. METAPHASE

16. Anaphase Observable Event
Double Chromosomes Split into Single Chromosomes
Caused by Mitotic Spindles Pulling Apart the Chromatids
Single Chromosomes move [pulled] to opposite ends of the cell.

17. ANAPHASE

18. Telophase Observable Events: “Reverse of Prophase”
DNA Decondenses from Chromosome form to Chromatin form
Nucleolus “Reappears”
Nuclear Membrane “Reappears”
Mitotic Spindles Disassemble

19. Telophase [continued]
Observable Events [continued]
Cytokinesis:
Division of the rest of the cell
Differs in Plant Cells and Animal Cells
Plant Cells
New Cell Wall and Cell Membrane form from the middle out toward the sides at the plane of division [ Cell Plate]

20. TELOPHASE

21. Telophase [continued]
Animal Cells:
In growing of the Cell Membrane from the perimeter toward the middle [Cleavage Furrow or Invagination of the Membrane]

22. TELOPHASE

23. Interphase
After Telophase is completed, each of the two genetically identical daughter cells enter G 1 of Interphase and begin the cycle again.