What are the steps in oogenesis?

Oogenesis describes the production of female gametes (ova) within the ovary The process begins during foetal development, when a large number of cells (oogonia) are formed by mitosis before undergoing a period of growth These cells begin meiosis but are arrested in prophase I until puberty At puberty, some follicles continue to develop each month is response to FSH secretion These follicles complete the first meiotic division to form two cells of unequal size The cell with less cytoplasm is a polar body (which degenerates), while the larger cell forms a secondary oocyte The secondary oocyte begins the second meiotic division but is arrested in prophase II (until fertilisation) It is released from the ovary (ruptured follicle develops into corpus luteum) and, if fertilisation occurs, will complete meiosisThe second meiotic division will produce an ovum and a second polar body

What are the steps in spematogenesis?

Spermatogenesis describes the production of spermatozoa (sperm) in the seminiferous tubules of the testes The first stage of sperm production requires the division of germline epithelium by mitosis These cells (spermatogonia) then undergo a period of growth This is followed by two meiotic divisions that result in four haploid daughter cells These haploid cells then differentiate to form sperm cells The developing sperm cells are nourished throughout by the Sertoli cells