Question

movement of the chromosomes during anaphase would be most affected by a drug that prevents which of the following processes?
formation of a cleavage furrow
elongation of microtubules
shortening of microtubules
cell wall formation
nuclear envelope breakdown

Explanation:

During anaphase, sister chromatids are separated and pulled to opposite poles of the cell. This movement is facilitated by the shortening of microtubules (spindle fibers) that are attached to the kinetochores of the chromosomes. If a drug prevents the shortening of microtubules, the movement of chromosomes during anaphase would be severely affected.

• Formation of a cleavage furrow occurs during cytokinesis (not directly related to chromosome movement in anaphase).
• Elongation of microtubules is more relevant to processes like spindle formation in earlier stages (prophase/metaphase) rather than the force - generating aspect for chromosome separation in anaphase.
• Cell wall formation is a feature of plant cell cytokinesis (not related to chromosome movement in anaphase).
• Nuclear envelope breakdown occurs in prophase (not related to the mechanism of chromosome movement in anaphase).

Answer:

shortening of microtubules