background information:
INTERPHASE
in a microscope nucleus would be seen as a spherical structure, would be unable to see chromosomes -- this is the interphase. this is when DNA replication occurs.
PROPHASE
nucleus membrane breaks down - prophase
chromosomes become visible - visible as a pair of "chromatids" (two copies)
LATE PHROPHASE
cell division proceeds - network of protein molecules (spindle and spindle fibres)
late phrophase - chrmosome pair will move towards spindle and join onto one fibre
METAPHASE
pair of chromatids are attached to spindle fibre by centromere.
characteristic - chromosomes are arranged across the middle. the 'equator' of the cell.
ANAPHASE
spindle fibre shortens pulling chromatids in different directions
pair of chromatids move apart to the poles of the cell
separation of the pair of chromatids
TELOPHASE
end of mitosis
nucleus begins to reform around the chromosomes at either end of the cell
new nucleus of two new cells
formation of two nucli at opposite ends of the cell
CYTOKINESIS
cell splits into two - not part of mitosis!
cell begins to move inwards to divide cytoplasm in half. - membrane fuses across equator to produce two cells
they each contain a chromosome that is the same as the parental cell
P - aPpear
M - Middle
A - Apart
T - Two
Cytokinesis is NOT part of Mitosis
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