Stages of Mitosis
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Transcript of Stages of Mitosis
Stages of Mitosis
Mitosis (M Phase)
The M Phase consists of:• Mitosis and Cytokinesis
Four Stages of Mitosis:Prophase MetaphaseAnaphaseTelophase
Late InterphaseCentrosome (with centriole pair)
Nuclear membrane
Nucleolus
Chromatin
Late Interphase
• Cell is preparing for division.
• Chromatin (relaxed form of DNA) has been replicated.
• Nuclear membrane and nucleolus are still visible.
Early & Late ProphaseSpindle apparatus
Centromere (where sister chromatids attach)
Nuclear membrane (disappearing)
Chromosomes made of two sister chromatids
Early & Late Prophase
• Chromatin condenses into chromosomes. • Nuclear membrane & nucleolus disappear. • Spindle apparatus forms.
MetaphaseCentrosome
Centromere
Equator or metaphase plate
Metaphase
• Chromosomes line up at imaginary line in the middle of the cell.
• Spindle apparatus is attached to the centromeres.
AnaphaseCentrosome
Shortening spindle apparatus
Anaphase
• Spindle apparatus shortens and chromatids are pulled apart.
Telophase & Cytokinesis
Animal cell “cleavage furrow”ORPlant cell “cell plate”
Chromosomes relaxing
Nuclear membrane reforming
Telophase & Cytokinesis
• Chromosomes arrive at opposite ends of the cell and begin to relax.
• Nuclear membranes reform and nucleoli reappear.
• Spindle apparatus disassembles.
Telophase & Cytokinesis
• Begins towards the end of mitosis.
• Microtubules help organelles and cytoplasm divide.
What’s the end product?
• Two identical daughter cells ready to start the cycle again… or not.
• Some cells (like your nerve and muscle cells) do not undergo division.
• For those that do (your skin and the lining of your intestinal tract) how would you know how quickly division takes place?
RE-identify the stages of Mitosis