Biology / Unit 4 Bio 0859 short lesson, about 20 seconds
Prometaphase and the Kinetochore
Captions available
The idea
Prometaphase is the stage where the nuclear envelope finishes fragmenting and each sister chromatid grows a kinetochore, a protein structure at the centromere that binds spindle microtubules.
In practice
Spindle microtubules extending from opposite poles attach to a chromosome's two kinetochores, one set from each pole.
Where people slip
A chromosome is not secured until both sister chromatids' kinetochores attach to microtubules from opposite poles.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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