bild

Sweat glands. Coloured scanning electron micrograph (SEM) of a group of three sweat glands (green) on the surface of the skin. These openings (pores) release sweat onto the surface of the skin. This has the effect of cooling the body, as the sweat's evaporation carries away heat. Magnification: x130 when printed 10cm wide. (KEYSTONE/SCIENCE PHOTO LIBRARY/STEVE GSCHMEISSNER)