When Cells Divide Mitosis By: Your teacher!© 1998
About Mitosis What is mitosis? Why is it important? The Phases of Mitosis Test your knowledge Review
What is Mitosis? How cells with nuclei reproduce One cell divides into 2 identical daughter cells. 5 stages (I.P.M.A.T.)
Why Mitosis? Allows multicellular organisms to grow 10 m of DNA in 10 um nuclear diameter Chromosomes = compact DNA & proteins, easy to move - facilitates division versus
Phases of Mitosis Interphase Prophase Metaphase Anaphase Telophase
Interphase Period I n-between divisions Nuclear membrane present DNA in loose strands for transcription Cell grows, DNA replicates (doubled)
Prophase Cell P repares to divide DNA condenses into doubled chromosomes Nuclear membrane disappears Spindle apparatus forms
Metaphase Chromosomes move to M iddle Spindle fibers attach at centromere (Kinetochores) Spindle apparatus stretches from pole to pole
Anaphase Chromatids move A way to poles Centromere splits 2 kinetochores Each chromosome 2 chromatids Spindle fibers contract pulling kinetochore/chromatid away
Telophase Cell T ears in T wo Nuclear membrane forms Chromosomes disperse Cytokinesis 2 identical “daughter” cells Both new cells in interphase
Phases of Mitosis Interphase - cell life I n-between divisions Prophase - cell P repares to divide Metaphase - chromosomes move to M iddle Anaphase - chromatids move A way Telophase - cell T ears in T wo
What is Mitosis ?
How cells with nuclei reproduce One cell divides into 2 identical daughter cells. 5 stages (I.P.M.A.T.)
Why Mitosis ? Which of these cells can divide it’s DNA evenly without damaging it?
Why Mitosis ? The bottom one! It’s DNA is condensed into chromosomes DNA in the top one cannot be divided
What Phase ? Chromosomes lined up in M iddle Spindle fibers attach at centromere (Kinetochores) Spindle apparatus stretches from pole to pole
It’s Metaphase! The chromosomes moved to the M iddle!
What Phase ? Period I n-between divisions Nuclear membrane present DNA in loose strands for transcription Cell grows, DNA replicates (doubled)
It’s Interphase! The cell is I n-between divisions
What Phase ? Chromatids move A way to poles Centromere splits 2 kinetochores Each chromosome 2 chromatids Spindle fibers contract pulling kinetochore/chromatid away
It’s Anaphase! Chromatids move A way to poles
What Phase ? Cell T ears in T wo Nuclear membrane forms Chromosomes disperse Cytokinesis 2 identical “daughter” cells Both new cells in interphase
It’s Telophase! Cell T ears in T wo
What Phase! Cell P repares to divide DNA condenses into doubled chromosomes Nuclear membrane disappears Spindle apparatus forms
It’s Prophase! The cell is P reparing to divide.
Mitosis = I.P.M.A.T. I nterphase - cell life I n-between divisions P rophase - cell P repares to divide M etaphase - chromosomes move to M iddle A naphase - chromatids move A way T elophase - cell T ears in T wo