What is the difference between mitosis and meiosis in terms of chromosome number?

• A. Mitosis yields two diploid identical cells; meiosis yields four haploid cells with half the chromosome number
• B. Mitosis yields four haploid cells; meiosis yields two diploid cells
• C. Mitosis yields two haploid cells; meiosis yields two diploid cells
• D. Mitosis yields four diploid cells; meiosis yields four haploid cells

Answer: (A)

How chromosome number changes during cell division. In mitosis, a somatic cell divides once after DNA replication to produce two daughter cells that are diploid and genetically identical to the parent, so the chromosome count stays the same. In meiosis, the cell divides twice after a single round of DNA replication, yielding four haploid daughter cells, each with half as many chromosomes as the original diploid cell. This reduction is essential for sexual reproduction because gametes fuse to restore the diploid number. For example, a human cell with 46 chromosomes would produce two cells with 46 each after mitosis, or four cells with 23 each after meiosis. This distinction is exactly captured by the description that mitosis yields two diploid identical cells and meiosis yields four haploid cells with half the chromosome number.