Figure 37.4: Gametogenesis Male and female germ cells proliferate by mitosis to produce an abundant supply of diploid cells that initiate and complete meiosis to produce sperm or ova. (A) Spermatogenesis. (B) Oogenesis. During oogenesis in many animals, the first polar body to be produced does not divide, so only two polar bodies are produced in total. 2n is the diploid number of chromosomes per cell; n is the haploid number. See Concept 7.4 for details of meiosis.