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blue You have probably encountered biofilms in which of these occasions? none true When you stepped on a slippery stone while crossing a stream or while swimming. Yes, Streams, ponds and lakes are a natural location for biofilms to grow and their slimy matrix can make for tricky footing. true When you were “grossed out” by the slimy mess coating your shower or shower curtain. Yes, Plastics are not immune to the growth of biofilms. As a matter of fact, no surface has yet been found on which biofilms will not grow. true Just before you decided that it was time for a trip to see the dental hygienist. Yes, The plaque on your teeth is a common biofilm and some of the residents of that plaque are responsible for dental caries. true When you sink backed up and you had to call the plumber to bring his/her snake. Yes, The nutrients we dump down the drain each day in the form of waste food are a banquet for the bacteria that form biofilms. They can become thick enough to clog a full sized drain pipe. That’s a lot of slime. Which of the following is true of biofilms that form in nature (not n the laboratory). none false They generally consist of a single species. No, Most biofilms in nature consist of many, perhaps hundreds of species. false They generally are found only under moderate conditions of temperature, pH, and salt concentration and pressure. No, biofilms have been found in the boiling hot springs of Yellowstone National Park, in the acid mine damaged streams of Appalachia, in the hypersaline Shark’s Bay in Australia and in the crushing pressure and super heated water of ocean thermal vents at the bottom of the ocean. false They cannot get a “grip” if the flow rate is high. No, Surprisingly, biofilms are able to get a grip even in extremely high flow rate habitats like dental water systems and high pressure water lines. As a general rule, the tougher you treat them, the better they grow. false They only form in relatively clean conditions, toxins are inhibitory to them. No, Acid mine damaged streams, the cyanide loaded waste ponds of gold mining operations, the heavily polluted ground water from leaking petroleum storage facilities, are all likely habitats for biofilm growth.