Section 9-2 Bio 30 NWRC
Mitosis is an important part of the cell cycle (click here for a review of the CC and a preview of Mitosis) • • • • •
Mitosis consists of 4 stages Prophase Metaphase Anaphase Telophase
Mitosis • Results in 2 genetically identical cells • Allows for organism growth • Allows damaged cells to be replaced
Interphase The cell is engaged in metabolic activity and performing its prepare for mitosis The cell grows replicates its DNA Interphase consists of G1, S and G2 stages
Prophase • Chromatin in the nucleus begins to condense (meaning it tightens into X shaped chromosomes)The nucleolus disappears.
Prophase • Some fibers cross the cell to form the mitotic spindle.
Early Prophase Late Prophase
Metaphase • Spindle fibers align the chromosomes along the middle of the cell nucleus. This line is referred to as the metaphase plate. This organization helps to ensure that in the next phase, when the chromosomes are separated, each new nucleus will receive one copy of each chromosome.
Anaphase • The paired chromosomes separate and move to opposite sides of the cell.
Telophase • Chromatids arrive at opposite poles of cell, and new membranes form around the daughter nuclei. The spindle fibers disperse, and cytokinesis or the partitioning of the cell may also begin during this stage.
Link to Interaction • Mitosis • A video to sum it all up
Cytokinesis • This is the process which actually divides the cytoplasm of the cell. • In plant cells, the rigid wall requires that a cell plate be synthesized between the two daughter cells.
Assessment • 1. A cell must undergo Cytokinesis in order for the cell division to be complete
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Assessment • 3. Chromosomes are not yet lined up in prophase – they resembles Xs and have centomeres
Assessment • 4. Prophase
Review • Much of this presentation comes from this website – visit it yourself to review