teratoma. [terâ²ÉtÅâ²mÉ] pl. teratomas, teratomata. a tumor composed of different kinds of tissue, none of which normally occurs together or at the site of the tumor. Teratomas are most common in the ovaries or testes.
The pink-colored film or ring frequently seen on showers, tubs, toilets and pet water bowls is typically caused by growth of the airborne bacteria Serratia marcesens. This harmless nuisance organism reacts with standing water and frequently forms during spring and summer months.
The rust-colored stains you find under your faucets or in your toilet turn up when iron meets air. Green or brown stains in the toilet usually indicate lime buildup. Lime scale forms as hard water evaporates and leaves a mineral buildup behind. As it dries, it picks up any dirt particles along with it, and slowly the stain builds, layer by layer, on the inside of the toilet bowl. Yuck!