M I T O S I S

1. MITOSIS

2. Mitosis is… • The process of cell growth & division *The splitting of the nucleus.

3. There are 5 parts of Mitosis: • IInterphase *Growth* • PProphase • M Metaphase • A Anaphase • T Telophase

4. Interphase Prophase Anaphase Telophase

5. Interphase • This cell shows how all cells look before mitosis. • Interphase is a phase of the cell cycle, but technically, NOT a stage of mitosis.

6. Prophase • The nuclear membrane breaks down. • The chromosomes shorten and thicken. • The other structures important for mitosis are also forming (ex. the centrioles).

7. Metaphase *The chromosomes are pulled to the cell's equator by the spindle fibers. *The chromosomes MEET IN THE MIDDLE

8. Detail… • Here's the confusing part - When the individual chromatids (½ of the "X") are separated from the chromosome (the "X"), • They are now, each referred to as a full chromosome.

9. In other words, the chromosome, composed of two chromatids, separates into the separate chromatids, which are then renamed chromosomes, even though they were only one half of a chromosome only moments before! - Whew!

10. Anaphase • The newly formed chromosomes are pulled by the spindle fibers toward opposite poles of the cell.

11. Telophase • The chromosomes stop moving. • The spindle fibers break down. • The membrane of the cell pinches creating two separate cells. • The nuclear membrane reforms. • The nucleolus reappears.

12. Very Last Part…Cytokinesis • This is when the two new cells completely divide. • Plant and Animal cells do this differently!

13. Animal Cell • A ring (contractile ring) tightens and tightens until the two new cells pinch apart. Cleavage Furrow

14. Plant Cell • A cell plate forms between the two cells and this forms into the cell wall eventually.