Movement of the chromosomes during anaphase would be most affected by a drug that prevents which of the following events in mitosis and cell division?
a) nuclear envelope breakdownb) elongation of microtubulesc) shortening of microtubulesd) formation of a cleavage furrow

The correct answer is: C) shortening of microtubules

Chromosome movement is possible thanks to changes in microtubule length. Several types of microtubules are involved. First, during the anaphase kinetochore microtubules shorten and consequently the chromosomes move toward the spindle poles. Then the astral microtubules that are anchored to the cell membrane pull the poles further apart. At the end of anaphase, the interpolar microtubules slide past each other and that additionaly separate the chromosomes.

a motor homunculus represents a map of brain areas dedicated to motor processing for different anatomical divisions of the body.

homunculus represents the importance of various parts of your body as seen by your brain. as a result, they take up a lot of brain space. although the cortical homunculus is a curiosity, penfield's work in mapping the brain's relationship to the body was invaluable.

a. by using fur or clothes to trap heat energy near the body