1. The Cell Cycle and Mitosis
Chapter 9 and 10.1

2. What is the cell cycle?
Repeating sequence of cellular growth and division throughout the life of an organism.

4. Cell division and why we care about it.

5. Interphase G1 Phase- Growth 1 S phase – DNA synthesis

8. G1 Phase- Growth 1
1st Growth Phase = (G1)
1. Cell grows rapidly and carries out routine functions
2. Phase takes most of the cell’s life
3. Muscle and nerve cells never divide, so they remain in G1

10. S phase- Synthesis Phase
Synthesis Phase (S)
1. Cell’s DNA is copied
2. At the end of the stage, each chromosome consists of 2 chromatids a centromere.

12. G2- Second Growth Phase Second Growth Phase (G2)
1. Hollow microtubules are assembled
2. Microtubules are used to move chromosomes during mitosis

14. M phase- Mitosis Mitosis 1. Nucleus is divided into 2 nuclei
2. Each nucleus ends up with the same number of chromosomes as the original cell.
3. Includes prophase, metaphase, anaphase and telophase.

15. Prophase The cell’s chromatin tightens.
Sister chromatids are attached at the centromere
Spindle fibers form in the cytoplasm
The nuclear envelope seems to disappear.
Spindle fibers attach to the sister chromatids

17. Prophase- Plant and animal cell

18. Metaphase
Sister chromatids are pulled along the spindle apparatus toward the center of the cell.
They line up in the middle of the cell.

20. Metaphase- Plant and animal cell

21. Anaphase The microtubules of the spindle apparatus begin to shorten.
The sister chromatids separate
The chromosomes move toward the poles of the cell.

23. Anaphase- Plant and animal cell

24. Telophase The chromosomes arrive at the poles and begin to relax.
Two new nuclear membranes begin to form and the nucleoli reappear
The spindle apparatus disassembles

26. Telophase- Plant and animal cell

27. Cytokinesis
In animal cells, microfilaments constrict, or pinch, the cytoplasm.
In plant cells, a new structure, called a cell plate, forms

29. Cytokinesis- Plant and animal cell

30. 9.2 Quiz What is the importance of Mitosis?
What are the 4 phases of Mitosis?
How do prokaryotic cells divide?