Summary OCR A/AS-Level Biology 2.6.2 Stages of Mitosis

Stages Of Mitosis
Early Prophase
 Chromosomes coil and condense (shorten and contract and thicken) into chromatids
 Chromatids take up stain mor easily and become more distinct
 Nucleolus is still present
 Centrioles divide

Late Prophase
 Nuclear membrane disintegrates
 Nucleolus shrinks and disappears
 Centrioles migrate to opposite poles

Metaphase
 Spindle fibres attach to centrioles and centromeres of chromatids
 Each centromere attaches to both poles by spindle fibres
 Chromatids line up at the equator

Anaphase
 Centromeres divide
 Chromatids are pulled apart towards the poles

Telophase
 Chromatids reach the poles and start to uncoil into chromosomes
 Chromosomes become less distinct
 Nuclear envelope starts to reform around each set of chromosomes