Homework Unit 3 Life Science Magazine Project | Page 4

Mitosis is used to replace dead cells or to produce new ones. Mitosis is part of the cell cycle. It has four phases: prophase, metaphase, anaphase, and telophase. Before mitosis occurs, interphase happens. Interphase is when the cell is not dividing. During interphase, the cell grows to about twice its size, carries out normal functions, the organelles duplicate, and DNA replicates. All these things are to prepare the cell for mitosis. The first step of mitosis is called prophase. During prophase, long strands of DNA condenses to chromosomes, each with two chromatids that are exact copies of each other. The nulear membrane also disappears. Then is metaphase. During metaphase, the chromosomes line up in the middle of the cell. Next is Anaphase. During anaphase, the chromatids spliet into two chromosomes. These chromosomes are pulled to the opposite sides of the cell. Finally, it is telophase. During telophase, a nuclear membrane forms around each group of chromosomes. After mitosis, cytokinesis occurs. It wraps up the cell division process. Cytokinesis is when the cell pinches and divides. Only eukaryotes can have the process mitosis because they have a nucleus, and prokaryotes don't. Below is the mitosis process.

Mitosis