What is the primary purpose of meiosis?

The primary purpose of meiosis is to produce gametes, which are the reproductive cells—sperms in males and eggs in females. During this specialized type of cell division, the chromosome number is halved from diploid (two sets of chromosomes) to haploid (one set of chromosomes). This reduction is crucial for sexual reproduction because when two gametes fuse during fertilization, they create a new organism with the correct diploid number of chromosomes.

Meiosis involves two consecutive divisions: meiosis I and meiosis II. In meiosis I, homologous chromosomes are separated, reducing the chromosome number by half. In meiosis II, the sister chromatids are separated, similar to what occurs in mitosis, but the cells remain haploid. This process ensures genetic diversity through crossing over and independent assortment, contributing to variation in offspring. Thus, meiosis plays a critical role in the life cycle of sexually reproducing organisms by ensuring that gametes contain a single set of chromosomes, allowing for proper genetic recombination and stable inheritance in successive generations.