Which of the following best describes the primary difference between mitosis and meiosis in eukaryotic cells?

• A. Mitosis results in genetic variation, while meiosis does not.
• B. Mitosis produces two genetically identical diploid cells, while meiosis produces four genetically unique haploid cells.
• C. Mitosis occurs only in gametes, while meiosis occurs in somatic cells.
• D. Mitosis involves two rounds of cell division, while meiosis involves only one.

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the purpose of mitosis and meiosis. Mitosis is a process of cell division that results in two genetically identical diploid cells, primarily for growth, repair, and asexual reproduction. Meiosis, on the other hand, is a specialized form of cell division that produces four genetically unique haploid cells, which are gametes (sperm and egg cells) used in sexual reproduction.
2. Step 2: Analyze the genetic outcomes of each process. Mitosis maintains the chromosome number of the parent cell (diploid, 2n), while meiosis reduces the chromosome number by half (haploid, n), ensuring genetic diversity in offspring.
3. Step 3: Compare the number of cell divisions. Mitosis involves a single round of cell division, while meiosis involves two rounds of cell division: meiosis I and meiosis II. This distinction is crucial for understanding the production of haploid cells in meiosis.
4. Step 4: Evaluate the genetic variation. Mitosis produces genetically identical cells, as there is no exchange of genetic material. In contrast, meiosis introduces genetic variation through processes like crossing over (exchange of genetic material between homologous chromosomes) and independent assortment of chromosomes.
5. Step 5: Eliminate incorrect options based on the above understanding. For example, mitosis does not occur in gametes, and meiosis does not occur in somatic cells. Additionally, meiosis involves two rounds of division, not one. The correct answer is: 'Mitosis produces two genetically identical diploid cells, while meiosis produces four genetically unique haploid cells.'