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Cell Division

Mitosis Cell cycle - - The repeating sequence of cellular growth and division during the life of an organism

Mitosis -the process during cell replication where the nucleus divides

1st: Interphase: prophase: __chromosomes coil up__ and become __visible__ during prophase and the __nuclear envelope dissolves and a spindle forms__

2nd: metaphase: during metaphase the __chromosomes line up along the equator__ and the __spindle fibers line the chromatids of each chromosome to opposite poles__

3rd. Anaphase: __centromers divided__ during anaphase and the __chromatides move toward opposite poles as spindle fibers shorten__

4th telophase: __a nuclear envelope forms around the chromosomes at each pole the chromosomes uncoil__ and __spindle dissolves__. __Cytokinesis begins at this point__

Cytokinesis: -cytoplasm of the cell is divided in half, and the cell membrane grows around each cell to enclose it, forming 2 seperate cells -In Animal Cells, the cell is pinched in half by a belt of proteins. In plant cells, the cell forms a cell plate which divides the cell in half. The Cell plate eventually becomes a cell wall and membrane

Chromosomes

Meosis - the process of creating reproductive Gametes from Germ Cells. There are 2 types in Humans: Spermatogenesis (the creation of sperm in Males) and Oogenesis (the creation of ovums in Females). -It is believed that meiosis was first used by protists to help repair their DNA and other genetic materials because the DNA repair enzymes become active during meiosis.