Post on 08-Jan-2018
description
Mitosis NotesMitosis 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 G1 phase – cell grows,
makes more organelles & proteins
S phase – chromosome replication (S = synthesis = “to make”)
G2 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
• http://www.cellsalive.com/mitosis.htm
• http://www.youtube.com/watch?v=CzPGhYiGyZ8• http://www.youtube.com/watch?v=vFf2dWZZtVg
Homework• Obj. 14.1 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)
Similarities Differences