MITOSISMITOSIS

Mitosis is… The process of cell growth & division There are 5 parts to it: –I Interphase*Growth* –P Prophase –MMetaphase –AAnaphase –TTelophase

Anaphase Interphase Telophase Prophase

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.

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

Metaphase *The chromosomes line up along the cell's equator and attach to the spindle fibers. *The chromosomes MEET IN THE MIDDLE

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

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

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.