Sperm production site. Coloured scanning electron micrograph (SEM) of a sectioned seminiferous tubule,the site of sperm production in the human testes. This tubule contains a swirl of the tails of forming sperm cells (purple) at its centre. The tubule is lined with a stratified epithelium containing two types of cell: Sertoli cells,which nourish developing sperm,and spermatogenic cells,from which the sperm cells form in a process known as spermatogenesis. After this,the sperm cells mature into their mobile form in a process known as spermiogenesis. Magnification: x360 when printed 10 centimetres wide. |