BIOD 171/Microbiology Lab 9 Exam Portage Learning BIOD 171 Essential Microbiology Lab Portage Learning Lab #9 Exam...Latest 11/2021 Questions and Answers

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6 / 6 pts Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. Given Culture A and Culture B were accidentally mixed, what observations we... re made from the Gram stain (shown below)? Your Answer: some of the bacteria are Gram positive which we can see in purple clusters , some other bacteria are Gram negative that they are pink and their shape are rod Gram-positive cocci (spherical) clusters and Gram-negative bacillus (rods) were observed. This study source was downloaded by 100000840903812 from CourseHero.com on 07-18-2022 23:29:26 GMT -05:00 https://www.coursehero.com/file/96114525/BIOD-171-Lab9examdocx/ Question 2 2 / 6 pts Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. Given the results from a MacConkey agar plate shown below, what is the shape of Culture A? Culture B? Your Answer: MacConkey is a selective media and only Gram negative bacteria grow on it Culture A- No growth Culture B- there is growth, culture B must be gram negative. MacConkey agar is selective for Gram-negative bacteria. Thus, Culture A must be Gram-positive as no growth was observed. Coupled to the results of the gram stain, Culture A (Gram-positive) must be the cocci. Culture B must be Gram-negative (growth observed) and this correlates to the bacillus or rod-shaped bacteria. what is the shape of Culture A? Culture B? Question 3 6 / 6 pts This study source was downloaded by 100000840903812 from CourseHero.com on 07-18-2022 23:29:26 GMT -05:00 https://www.coursehero.com/file/96114525/BIOD-171-Lab9examdocx/ Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. The hemolytic properties of both cultures were next examined by streaking each culture on a blood agar plate (shown below). What is the hemolytic status of Culture A? Culture B? Your Answer: it indicates beta hemolysis, because of the lyses in red blood cells the agar has change of color Culture B, it grows but it does not have any lyses quality Culture A exhibits beta hemolysis as defined by the region of clearing around the growing bacterial streak. Culture B exhibits gamma-hemolysis (non-hemolytic) as indicated by the white colonies growing on the still red agar. Question 4 6 / 6 pts Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. Culture A and Culture B were assessed via the coagulase test as shown below. State your observations for each culture. This study source was downloaded by 100000840903812 from CourseHero.com on 07-18-2022 23:29:26 GMT -05:00 https://www.coursehero.com/file/96114525/BIOD-171-Lab9examdocx/ Your Answer: Culture A is completely inverted and we can see coagulation, so it is coagulase positive Culture B is still liquid and it is coagulase negative Culture A is coagulase positive. The inverted tube showcases the clotting/hardening effect. This strongly suggests Culture A is Staph aureus as shown in the Lab#6 coagulase test. Culture B is coagulase negative. The tube could not be inverted as the culture was entirely in liquid form. Question 5 6 / 6 pts Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. 1. Culture A and Culture B were streaked onto EMB plates. What does this tell you about each of the cultures? Describe your observations. This study source was downloaded by 100000840903812 from CourseHero.com on 07-18-2022 23:29:26 GMT -05:00 https://www.coursehero.com/file/96114525/BIOD-171-Lab9examdocx/ Your Answer: there is no growth in culture A in culture B there is growth and it fermented lactose and we can obviously see green metallic color EMB agar is both selective and differential media. EMB restricts Gram-positive and as such this again confirms Culture A is Gram-positive. Culture B clearly grew on the EMB plate, further confirming it is Gram-negative. A green metallic sheen was also observed which immediately suggests Culture B is E. coli. Question 6 6 / 6 pts Using the observations made and recorded from PL09 Unknown Pathogen, complete the results sections accordingly. Culture A and Culture B were assessed via the catalase test as shown below. State your observations for each culture. This study source was downloaded by 100000840903812 from CourseHero.com on 07-18-2022 [Show More]

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