What occurs during mitosis? Choose the correct answer.

• A. The cell undergoes cytokinesis without any changes to the nucleus.
• B. The nucleus divides to produce two genetically identical daughter nuclei.
• C. DNA is replicated, doubling the chromosome number.
• D. Homologous chromosomes pair and exchange genetic material.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the process of mitosis. Mitosis is a type of cell division that results in two genetically identical daughter nuclei, ensuring that each daughter cell has the same number of chromosomes as the parent cell.
2. Step 2: Clarify the stages of mitosis. Mitosis consists of several phases: prophase, metaphase, anaphase, and telophase. During these stages, the nucleus divides, and the chromosomes are evenly distributed to the daughter nuclei.
3. Step 3: Eliminate incorrect options. For example, cytokinesis is the division of the cytoplasm, not the nucleus, and occurs after mitosis. DNA replication occurs during the S phase of interphase, not during mitosis. Homologous chromosome pairing and genetic exchange occur during meiosis, not mitosis.
4. Step 4: Focus on the correct answer. The defining feature of mitosis is the division of the nucleus to produce two genetically identical daughter nuclei.
5. Step 5: Summarize the key concept. Mitosis ensures genetic consistency by dividing the nucleus and distributing identical sets of chromosomes to the daughter cells.