Meiosis is a special type of cell division necessary for sexual reproduction. These are sperm producing cells of a male crane fly, a species with only eight chromosomes per cell. During meiosis, the cell divides twice, producing four haploid cells containing one copy of each chromosome.
The first meiosis division separates pairs of homologous chromosomes, creating two haploid cells with only one set of chromosomes. The second division separates the chromatids of each chromosome. The end result is a production of four haploid cells, each with a single chromatid from each chromosome.
When haploid sperm and egg unite during fertilization, the resulting cell is diploid, having received one chromosome of each pair from each parent.