What is the primary type of cell division involved in the formation of gametes?

The primary type of cell division involved in the formation of gametes is meiosis. This specialized form of cell division reduces the chromosome number by half, creating four non-identical daughter cells, each with a haploid set of chromosomes. This reduction is crucial for sexual reproduction because when gametes (sperm and egg) fuse during fertilization, they restore the diploid chromosome number in the resulting zygote.

Meiosis consists of two rounds of cell division—meiosis I and meiosis II. In meiosis I, homologous chromosomes are separated, leading to genetic variation through processes like crossing over and independent assortment. In meiosis II, sister chromatids are separated, resulting in gametes that are uniquely genetic combinations of the parent organism's genes.

This unique division process ensures that offspring have genetic diversity, which is important for evolution and adaptation in changing environments. Therefore, meiosis is the fundamental mechanism for generating gametes necessary for sexual reproduction.