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blue Biofilms grow in . . . none true streams Yes. Biofilms grow in streams such as the one in the picture shown in this section. true Antarctica Yes. Extremophilic, or extreme-loving, organisms are found in biofilms that grow in both hot and cold climates. true deserts Yes. One common form of desert biofilm is the desert varnish that grows on rocks and canyon walls in deserts. true the human body Yes. We have communities of microbes living on and in us; for example, biofilms can grow on our mucous surfaces, in our digestive tract, on and in layers of our skin, and on our teeth as dental plaque. true deep ocean vents Yes. In fact biofilms seem to be the first living things to grow around newly formed vents. Which of the following are required for a biofilm to grow? none true a surface Yes. Biofilms begin to form when certain microorganisms adhere to the surface of some object. false high temperatures No. While some biofilms do thrive in hot environments like the hot springs of Yellowstone National Park, other such as those that grow in streams do not require high temperatures. true nutrients Yes. All living things require nutrients, and biofilms contain living organisms. true microorganisms Yes. Microorganisms play a major roles in biofilm formation by secreting substances (EPS) that help hold biofilm colonies together. true moisture Yes. Biofilms need at least some moisture to grow, but there are forms such as those that grow in deserts that have developed methods for surviving dry periods. Which of the following are human health effects that biofilms can cause? none true urinary tract infections Yes. Table 1.2 provides evidence that biofilms play a role in many medical contexts, including urinary tract infections. false biofouling No. Biofouling is a term that relates to contamination and fouling in industry. true Otitis media Yes. Table 1.2 shows evidence that biofilms play a role in many medical contexts, including Otitis media, which is an infection of the middle ear. true dental cavities Yes. Dental carries or cavities are result of bacterial infection (and biofilms). true peptic ulcers Yes. Evidence shows that it is not stress, but bacterial communities of Helicobacter pylori that cause peptic ulcers. Biofilms cause which of the following problems in industry? none true pipe corrosion Yes. The presence of biofilms on a pipe surface can substantially increase corrosion and subsequent pipe deterioration. true cooling tower fouling Yes. The slide show in this section of the hypertextbook showed biofilms growing on cooling tower fill and explained that the accumulated weight of biofilms can cause the collapse of fill material. true clogging heat exchangers in power plants Yes. The slide show in this section of the hypertextbook presented an example and pointed out that properly functioning heat exchangers are important for safe and efficient power plant operations. true water contamination Yes. Biofilms can form on surfaces that carry water and can cause the water to become contaminated. false fouling drying ovens No. Even biofilms have their limits and such extremely hot and dry environments do not support biofilms.