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Biology

MEIOSIS 1

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Interphase

 Chromosomesreplicate to form

sisterchromatids

 Chromosomes

are not visible. Centriolereplicates.

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Prophase 1

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Prophase 1

• Chromosomes coil and become

shorter, thicker and visible under the light microscope.

• Homologous chromosomes

come together to form bivalents by synapsis forming a tetrad (Each pair, ith four chromatids!

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Prophase 1•

Synapsis – the pairing ofhomologous

chromosomes

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Prophase 1: rossingover

hromatidse!changeportions oftheirchromatidsat

chiasmata"

• "on#sister chromatids e$change

genetic material through the process ofcrossing over.

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rossing over

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•entrioles move toopposite poles ithspindle #bres beteenthem.

•

$ucleolus and nuclearenvelope disappear"

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 %&E E"'