STEVE GSCHMEISSNER / SCIENCE PHOTO LIBRARY STEVE GSCHMEISSNER / SCIENCE PHOTO LIBRARY
Sperm production site. Coloured scanning electron micrograph (SEM) of sectioned seminiferous tubules, the sites of sperm production in the human testes. Each tubule contains a swirl of the tails of forming sperm cells (white/green) at its centre. The tubules are 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. Then, the sperm cells mature into their mobile form in a process known as spermiogenesis. Each testis has about 500 of these tubules that are 30-70cm long. Magnification: x70 when printed 10cm wide.
Model release not required. Property release not required.