Consider an animal cell in which motor proteins in the kinetochores normally pull the chromosomes along the kinetochore microtubules during mitosis. Suppose, however, that during metaphase, this cell was treated with an inhibitor that blocks the function of the motor proteins in the kinetochore, but allows the kinetochore to remain attached to the spindle. The inhibitor has no effect on any other mitotic process, including the function of the nonkinetochore microtubules.

Answer yes or no to the following three questions concerning this animal cell that has been treated with the inhibitor:

- A. B.
Will this cell elongate during mitosis?

- A. B.
Will the sister chromatids separate from each other?

- A. B.
Will the chromosomes move to the poles of the cell?

A.
no

B.
yes

1. The cell will elongate during the process of mitosis as the drug inhibits the binding of the motor proteins to the kinetochore but not the process of elongation therefore yes is correct.

2. The kinetochore is the proteins which attach to the centromere position to which the microtubules attach, the kinetochore help in the movement of the chromosomes towards the opposite poles but the separation of the chromatids does not involve motor proteins and they will separate.

3. Since the chromosome movement requires the motor proteins therefore the chromosomes will not move towards the opposite poles and therefore no is correct.