In which phase of mitosis do the sister chromatids pull apart?

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

Answer: (B)

Verified step by step guidance

1. Understand the process of mitosis, which is the division of a single cell into two genetically identical daughter cells. Mitosis consists of several phases: prophase, metaphase, anaphase, and telophase.
2. Recall that sister chromatids are identical copies of a chromosome connected by a centromere. During mitosis, these chromatids need to be separated to ensure each daughter cell receives an identical set of chromosomes.
3. Review the phases of mitosis: In prophase, chromosomes condense and become visible. In metaphase, chromosomes align at the cell's equatorial plane. In anaphase, sister chromatids are pulled apart toward opposite poles of the cell. In telophase, the cell prepares to divide into two daughter cells.
4. Focus on anaphase: During this phase, the centromeres split, and the spindle fibers shorten, pulling the sister chromatids apart to opposite ends of the cell. This separation is crucial for equal distribution of genetic material.
5. Conclude that the phase in which sister chromatids pull apart is anaphase, as this is when the chromatids are separated and moved to opposite poles, ensuring each new cell will have the correct number of chromosomes.