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.
Pink algae is not really an algae, it is a type of bacteria. When the bacteria colonise a surface you will notice it in the form of a pink or clear slimy layer. Pink algae (i.e. pink bacteria colonies) are not very common in aquariums but they do occur.