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blue In/on which of these might you expect to find biofilms growing? none true Swimming pool Yes, Any habitat that has a surface exposed to water is a likely place for biofilms to grow. true Frozen deserts of the Antarctic Yes, Any habitat that has a surface at least occasionally exposed to water is a likely place for biofilms to grow. true A shower curtain Yes, Any habitat that has surface a exposed to water is a likely place for biofilms to grow. true A host organism Yes, Any habitat that has a surface exposed to water is a likely place for biofilms to grow. Which of the following is a requirement for the formation of biofilms? none true Water Yes, water is required for the growth of all biofilm. true Microorganisms, bacteria, algae, fungi Yes, Although inorganic and organic materials can deposit on surfaces exposed to water, it is not a biofilm unless microorganisms are present true Nutrients Yes, Many biofilms can grow in extremely low nutrient conditions, but some nutrient is always required false Nitric oxide No, Nitric oxide serves a hormonal effect in many higher organisms but it is not required for the formation of biofilms true A conditioning film Yes, There is evidence that microorganisms will adhere only to surfaces that have a prior deposit of proteins, polysaccharides and other organic materials, that is a conditioning film Traditional light microscopes and electron microscopes were the first instruments used to visualize biofilms. Each of these had limitations due to the special characteristics of biofilm. Which of these were limitations of light and electron microscopy? none true Light or brightfield microscopy generally requires staining in order to visualize individual microbial cells. Staining usually kills the subject under examination. Yes, Staining often requires either chemical or heat fixation which kills cells and destroys biofilm structure true Light microscopy used visible light, and microorganisms are transparent making them difficult to visualize with out staining. Yes, Transparent cells are difficult to observe without staining true Electron microscopy has very high resolution but requires the dehydration of the subject being examined. Yes, Biofilms are mostly water and dehydration destroys biofilm structure. true In light microscopes, light enters the objective lens from various depths within the biofilm due to the depth of field of the lens. This makes it difficult to observe cells in the biofilm at any given level. Yes, The large depth of field permits light to enter the objective from various depths within the biofilm making imaging difficult.