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The separation of the poles of the cell during anaphase is accomplished by ____________

-contraction of overlapping microtubules

-contraction of nonoverlapping microtubules

-the sliding of overlapping microtubules from opposite poles over one another in the same direction

-the sliding of overlapping microtubules from opposite poles over one another in opposite directions

-expansion of microtubules from the center of the cell toward the poles

User Mejonzhan
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Final answer:

Cell poles separate during anaphase by the action of polar microtubules sliding past each other in opposite directions, facilitated by the motor protein dynein, leading to cell elongation.

Step-by-step explanation:

The separation of the poles of the cell during anaphase is accomplished by the sliding of overlapping microtubules from opposite poles over one another in opposite directions. During this phase, polar microtubules, which extend from centrioles or microtubule-organizing centers (MTOCs) at opposite poles, overlap at the cell's center.

The motor protein dynein, attached to these microtubules, facilitates their sliding movement by hydrolyzing ATP. As this happens, dynein on the microtubules from one pole 'walks' along those extending from the opposite pole. This motion, orchestrated primarily by non-kinetochore microtubules, contributes to cell elongation by pushing the poles apart.

Furthermore, kinetochore microtubules assist in pulling the sister chromatids toward the poles as the cell elongates. It is this elegant interplay of microtubule dynamics that ensures successful cellular division and the faithful segregation of chromosomes into daughter cells.

User Epitka
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