Which stage do sister chromatids break apart and are pulled to opposite ends of the nucleus?

Which stage do sister chromatids break apart and are pulled to opposite ends of the nucleus?

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

Answer: (B)

Sister chromatids separate and are pulled to opposite ends of the cell during anaphase. At the start of this stage, cohesin proteins that hold the sister chromatids together at the centromeres are cleaved, releasing the paired chromatids. Once separated, kinetochore microtubules shorten and motor proteins pull the chromatids toward opposite poles. Nonkinetochore microtubules push the poles farther apart, aiding the separation. This movement sets up two distinct sets of chromosomes that will be enclosed by new nuclear envelopes in the next phase.

Sister chromatids separate and are pulled to opposite ends of the cell during anaphase. At the start of this stage, cohesin proteins that hold the sister chromatids together at the centromeres are cleaved, releasing the paired chromatids. Once separated, kinetochore microtubules shorten and motor proteins pull the chromatids toward opposite poles. Nonkinetochore microtubules push the poles farther apart, aiding the separation. This movement sets up two distinct sets of chromosomes that will be enclosed by new nuclear envelopes in the next phase.