At which phase of the cell cycle do centrosomes begin to move apart in animal cells?

At which phase of the cell cycle do centrosomes begin to move apart in animal cells?

• A. Telophase
• B. Metaphase
• C. Anaphase
• D. Prophase

Answer: (D)

During prophase, which marks the beginning of mitosis, the centrosomes play a crucial role in the formation of the mitotic spindle. As they begin to move apart, they are actively reorganizing microtubules that will later help separate the chromosomes. This movement is essential for establishing the bipolar spindle apparatus that is necessary for accurately segregating the chromosomes during the later phases of mitosis. In this phase, each centrosome migrates to opposite poles of the cell, and the mitotic spindle begins to form. This dynamic rearrangement of centrosomes sets the stage for the proper alignment and distribution of chromosomes in subsequent phases. The other phases, while critical in their own right, do not involve the initial movement of centrosomes. In metaphase, the chromosomes are aligned at the cell's equator, and the centrosomes have already been positioned. Anaphase is primarily characterized by the separation of sister chromatids pulling toward opposite poles, and by telophase, the cell is already on the brink of completing division, focusing on reformation of the nuclear envelope rather than any movement of the centrosomes.

During prophase, which marks the beginning of mitosis, the centrosomes play a crucial role in the formation of the mitotic spindle. As they begin to move apart, they are actively reorganizing microtubules that will later help separate the chromosomes. This movement is essential for establishing the bipolar spindle apparatus that is necessary for accurately segregating the chromosomes during the later phases of mitosis.

In this phase, each centrosome migrates to opposite poles of the cell, and the mitotic spindle begins to form. This dynamic rearrangement of centrosomes sets the stage for the proper alignment and distribution of chromosomes in subsequent phases.

The other phases, while critical in their own right, do not involve the initial movement of centrosomes. In metaphase, the chromosomes are aligned at the cell's equator, and the centrosomes have already been positioned. Anaphase is primarily characterized by the separation of sister chromatids pulling toward opposite poles, and by telophase, the cell is already on the brink of completing division, focusing on reformation of the nuclear envelope rather than any movement of the centrosomes.