Which event during anaphase would be most directly impacted by a drug that prevents the shortening of microtubules?

Which event during anaphase would be most directly impacted by a drug that prevents the shortening of microtubules?

• A. Separation of sister chromatids
• B. Formation of the nuclear envelope
• C. Cytokinesis initiation
• D. Chromosome condensation

Answer: (A)

During anaphase, the separation of sister chromatids is primarily driven by the shortening of microtubules that connect to the kinetochores of chromosomes. As the microtubules pull the chromatids apart toward opposite poles of the cell, the effective shortening of these microtubules is crucial for this process to occur. If a drug inhibits the shortening of microtubules, this fundamental action would be obstructed, preventing the chromatids from being pulled apart and thus thwarting their separation. The other options involve different processes unrelated to the mechanical action of microtubule shortening in anaphase. The formation of the nuclear envelope takes place post-anaphase during telophase, while cytokinesis initiation is a process that involves the actin and myosin filaments rather than microtubules directly. Chromosome condensation occurs during prophase, prior to anaphase, making it also unrelated to the events of anaphase itself. Thus, the direct impact of a drug preventing microtubule shortening would unmistakably affect the separation of sister chromatids.

During anaphase, the separation of sister chromatids is primarily driven by the shortening of microtubules that connect to the kinetochores of chromosomes. As the microtubules pull the chromatids apart toward opposite poles of the cell, the effective shortening of these microtubules is crucial for this process to occur. If a drug inhibits the shortening of microtubules, this fundamental action would be obstructed, preventing the chromatids from being pulled apart and thus thwarting their separation.

The other options involve different processes unrelated to the mechanical action of microtubule shortening in anaphase. The formation of the nuclear envelope takes place post-anaphase during telophase, while cytokinesis initiation is a process that involves the actin and myosin filaments rather than microtubules directly. Chromosome condensation occurs during prophase, prior to anaphase, making it also unrelated to the events of anaphase itself. Thus, the direct impact of a drug preventing microtubule shortening would unmistakably affect the separation of sister chromatids.