Color-enhanced SEM of fecal bacteria. Microorganisms in human feces consist of bacteria of many genera and species. Digested portions of the foods are also noticeable. The high concentration of bacteria in the feces shown by enhanced scanning electron microscopy points to the need to wash hands after the use of a toilet in order to prevent the transfer of bacteria to foods. Image width: 10.7 micrometers. Magnification: 9,345x if the image is printed 10 cm wide.