It is derived from an algae also known as seaweed and

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It is derived from an algae, also known as seaweed and creates the solid medium called agar. Seaweed (algae) extract. 1 / 2 pts Ques ! on 6 Blood agar is which type of medium? Select all that apply. Di ff eren # al Correct! Correct! Blood agar can be used to di ff eren # al between species based on its hemoly # c ac # vity. Selec # ve Enriched Correct Answer Selec # ve and Di ff eren # al 5 / 5 pts Ques ! on 7 Match the following hemoly # c class with its descrip # on of ac # vity. 1. Alpha hemolysis A. No hemoly # c ac # vity 2. Beta hemolysis B. Incomplete hemoly # c ac # vity 3. Gamma hemolysis C. Complete hemoly # c ac # vity B 1 Correct! Correct! C 2 Correct! A 3 Correct! Correct! 2 / 2 pts Ques ! on 8 Columbia CNA agar is most closely related to which media: EMB agar Tryp # case Soy Agar Blood agar Correct! Correct! CNA agar is similar to BAP as it is also enriched with blood and allows for di ff eren # a # on based on hemoly # c pa ! erns. MacConkey Agar 2 / 2 pts Ques ! on 9 True or False: Chocolate agar gets its brown color from cocoa to produce an enriched media. True False Correct! Chocolate (cocoa) is never added to the media. The name is derived simply based on the color that actually comes from the presence of ‘cooked’ (lysed) red blood cells in the media. Your Answer: 5 / 5 pts Ques ! on 10 An unknown microbe is streaked onto a MacConkey agar plate. A $ er an overnight incuba # on at 37°C, growth is observed. Would a Gram stain be necessary? Why or why not? A gram stain would not be necessary as restricts gram-posi # ve bacterial growth. If a growth occured, we know that it is a gram nega # ve microbe. The color of the base of the agar plate changes as the microbes consume the nutrients within the agar. Therefore, no gram stain would be necessary. No. A Gram stain would not be necessary, as only only Gram-Nega ! ve microbes will grow on MacConkey agar. Your Answer: 10 / 10 pts Ques ! on 11 In an a ! empt to detect the presence of the pathogenic strain of E. coli O157:H7, a researcher spread a culture onto a MacConkey agar with failed results. What type of agar should they (correctly) try next? Why? The pathogenic strain of E.coli 0157:H7 is di ff erent from the other E. Coli strains as it is unable to ferment sorbitol. MacConkey plates contain sorbitol, instead of lactose to tell the di ff erence between non-pathogenic strains of E.coli and pathogenic. The researcher should try an EMB plate next, or an Eosin Methylene Blue Agar next as it is similar to the SMAC plate as lactose fermen # ng microbes will produce colonies on the surface of the agar. If it is present, it will show as a metallic green color on the EMB agar plates. The microbe should be plated on SMAC (Sorbitol-MacConkey agar) as it is specifically formulated to detect O157:H7. Pathogenic E. coli (O157:H7) cannot ferment sorbitol while non-pathogenic E. coli can ferment both soribitol and lactose. Therefore, colonies that ferment (acidic condi ! ons; non- pathogenic) can be di ff eren ! ated from non-fermenters (neutral to basic condi ! ons; pathogenic).

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