Oogenesis is the production and growth of the ova (egg cells) in the animal ovary. Special cells (oogonia) within the ovary divide repeatedly by mitosis to produce large numbers of prospective Egg cells (primary oocytes). When mature, these undergo meiosis, which halves the number of chromosomes. During die first meiotic division a polar body and a secondary oocyte are rooked. At the second meiotic division the abecedary oocyte produces an ovum and a cord polar body. Oocytes may be present in due- ovaries at birth and may represent the total number of eggs to be produced.