Stages of Mitosis

Mitosis (M Phase) The M Phase consists of: Mitosis and Cytokinesis Four Stages of Mitosis: P rophase M etaphase A naphase T elophase

Late Interphase Centrosome (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 Prophase Spindle 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.

Metaphase Centrosome 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.

Anaphase Centrosome Shortening spindle apparatus

Anaphase Spindle apparatus shortens and chromatids are pulled apart.

Telophase & Cytokinesis Animal cell “cleavage furrow” OR Plant 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