Mitosis Notes

CELL DIVISION 1 cell ÷ into 2 identical daughter cells (same genetic info) Eukaryotes (cells w/ nucleus) go through 2 stages of ÷ Mitosis – ÷ of nucleus –Cytokinesis – ÷ of cytoplasm

Cell cycle = Life span of the cell  G 1 phase – cell grows, makes more organelles & proteins  S phase – chromosome replication (S = synthesis = “to make”)  G 2 phase – molecules & organelles required for cell ÷ produced  M phase – mitosis & cytokinesis S phase G1 phase G2 phase

Cell cycle = Life span of the cell cont… G1, S and G2 make up INTERPHASE. Cell spends a majority of its life in this phase. M phase is CELL ÷. Relatively small portion of cell’s life.

MITOSIS 4 phases of nuclear division

Prophase Longest phase of mitosis Chromosomes become visible Centriole pairs begin to separate Spindle fiber forms (made of microtubules) Nuclear envelope breaks down Spindle begins to attach to chromosomes at centromere

Metaphase Chromosomes line up across center of the cell Centromere connected to spindle fibers Centriole pairs at opposite ends of cell

Anaphase Sister chromatid split apart Chromosomes get pulled to opposite poles by shrinking spindle fibers Chromosomes form “V” shape as they get dragged through the cytoplasm

Telophase Chromosomes decondence Nuclear envelope reforms around each set of chromosomes at opposite ends of cell Spindle fiber breaks apart 2 nuclei are formed

Cytokinesis ÷ of cytoplasm 2 new daughter cells are formed w/ same number of chromosomes as original cell.

Video of Mitosis Mitosis Movie

Homework Obj and 14.2 (Meiosis) Make a special table where you write similarities and differences between Meiosis and Mitosis or a Venn Diagram Discuss and stamp Wednesday Current Event due Friday Friday, last day to turn in progress reports (signed) SimilaritiesDifferences