During anaphase, sister chromatids separate to move to opposite poles of the cell.

During anaphase, sister chromatids separate to move to opposite poles of the cell.

• A. Chromatids separate to opposite poles
• B. Nuclear envelope forms
• C. Chromosomes align at the equator
• D. Spindle fibers disassemble

Answer: (A)

Anaphase is the stage of mitosis when sister chromatids separate and are pulled toward opposite poles. This separation happens after cohesin is cleaved, and the kinetochore microtubules shorten, pulling the chromatids apart. The poles are pushed further apart as nonkinetochore microtubules lengthen, helping move the chromatids toward opposite ends of the cell. The option describing chromatids separating to move to opposite poles captures this exact event, so it’s the best choice. The other options describe processes from other stages: the nuclear envelope reforms around each set of chromosomes in telophase, chromosomes align at the cell’s equator in metaphase, and spindle fibers disassemble later in mitosis during telophase/cytokinesis.

Anaphase is the stage of mitosis when sister chromatids separate and are pulled toward opposite poles. This separation happens after cohesin is cleaved, and the kinetochore microtubules shorten, pulling the chromatids apart. The poles are pushed further apart as nonkinetochore microtubules lengthen, helping move the chromatids toward opposite ends of the cell. The option describing chromatids separating to move to opposite poles captures this exact event, so it’s the best choice. The other options describe processes from other stages: the nuclear envelope reforms around each set of chromosomes in telophase, chromosomes align at the cell’s equator in metaphase, and spindle fibers disassemble later in mitosis during telophase/cytokinesis.