What specifically separates during anaphase of mitosis?

• A. Nuclear envelope
• B. Cytoplasm
• C. Homologous chromosomes
• D. Sister chromatids

Answer: (D)

Verified step by step guidance

1. Understand the context of mitosis: Mitosis is a process of cell division that results in two genetically identical daughter cells from a single parent cell. It consists of several phases: prophase, metaphase, anaphase, and telophase.
2. Identify the key event in anaphase: During anaphase, the main event is the separation of sister chromatids. These are identical copies of a chromosome that were duplicated during the S phase of the cell cycle.
3. Differentiate between sister chromatids and homologous chromosomes: Sister chromatids are identical copies of a single chromosome, connected by a centromere. Homologous chromosomes, on the other hand, are a pair of chromosomes (one from each parent) that have the same genes but may have different alleles.
4. Describe the mechanism of separation: During anaphase, the spindle fibers attached to the centromeres shorten, pulling the sister chromatids apart toward opposite poles of the cell. This ensures that each daughter cell will receive an identical set of chromosomes.
5. Clarify what does not separate during anaphase: The nuclear envelope and cytoplasm do not separate during anaphase. The nuclear envelope breaks down earlier in mitosis, and the cytoplasm divides during cytokinesis, which occurs after telophase.