The Stages of Mitosis
Mitosis Stages
Stages of Cell Mitosis
9 th grade Biology
By Mr. C. Swartz, September 25, 2011
Stage 1: Interphase
• DNA has replicated.
• Structure is loose; not yet the solid structure of a chromosome.
• Nuclear membrane still intact (protects DNA from mutation)
Stage 2: Prophase
• DNA molecules shorten and condense by coiling, to form chromosomes.
• Nuclear membrane and nucleolus no longer present.
• Spindle apparatus has migrated to opposite poles of cell.
Stage 3: Metaphase
• Spindle fibres attach themselves to centromeres in chromosomes.
• The fibres align the chromosomes at the equatorial plate.
Stage 4: Anaphase
• Spindle fibres shorten.
• Centromere splits.
• The result: sister chromatids pulled behind centromeres
Stage 5: Telophase
• Chromosomes reach the poles of their spindles.
• Nuclear envelope reforms.
• Chromosomes uncoil, and spindle fibres disintegrate.
Credits
Permission from:
Page 3: http://www.ivyrose.co.uk/HumanBody-
Images/Cell_Structures/Prophase-
Early_cIvyRose.jpg
All other images provided by C. Swartz, referencing: http://library.thinkquest.org/C0118084/Gene/C hromosomal_Inheritance/StagesMitosis.htm
