Which cell division produces reproductive cells in sexually reproducing organisms?

• A. Mitosis
• B. Cytokinesis
• C. Binary Fission
• D. Meiosis

Answer: (D)

Reproductive cells in sexually reproducing organisms are formed by a division that halves the chromosome number and generates genetic variation. This division is meiosis. It involves two successive rounds of division, producing four haploid gametes from a single diploid cell. During Meiosis I, homologous chromosomes pair up and exchange genetic material through crossing over, and the way these pairs line up and separate creates new combinations of genes. Independent assortment during this process further increases genetic diversity. The result is gametes with half the original number of chromosomes, ready to fuse with a gamete from another individual to restore the species’ diploid chromosome number after fertilization.

In contrast, mitosis keeps the chromosome number the same to create identical somatic cells for growth and tissue maintenance. Cytokinesis is the process that splits the cell’s cytoplasm after division, occurring alongside mitosis or meiosis. Binary fission is a form of asexual reproduction in some single-celled organisms and does not involve producing gametes.