Microbiology lab practical final ex 7, 8, 9,11 Questions With Complete Solutions

FeCl3 Used in a PAA agar to detect presence of phenylpyruvic acid positive green color. MAC agar What stain do you do on Day 1 of the unknown lab? You may Gram stain from your unknown broth to confirm if the bacteria are Gram-positive or Gram-negative. A throat culture performed by using a throat swab is used to detect which organism that causes strep throat? Group A Streptococcus Bacteria Which staphylococci is the most important bacteria in human disease? Staphylococcus Aureus Which organisms did we work with in class are virulent pathogens? 1. E. coli 2. S. marcescens 3. P. vulgaris 4. S. typhimurium 5. P. aeruginosa 6. K. pneumoniae Which organism is the most common cause of diaper rash in infants? Candida In the Unknown Lab (not the virtual) what do you do on Day 1? EMB (eosin-methylene blue agar) plate, MAC (MacConkey agar) plate PEA (phenylethyl alcohol agar) plate. Which two are Gram-Negative Lactose Fermentation ? EMB and MAC Which one is Gram-positive? PEA EMB Test Results Gram- negative Lacose Fermentation selective Gram+ organisms *Light pink (-) not fermenting *Dark purple (+) slow fermenters acidic *Metallic green/blue black (+) strong vigorous lactose fermenters acidic EMB agar (eosin methylene blue) PEA agar (Phenyl Ethyl agar) MAC (MacConkey) Test Results Lactose fermentation Selective for Gram-negative reddish/pink= positive ferments lactose acid Yellow= no lactose fermenting No growth no colonies it's Gram (+) A) Lactose negative Gram(-) lactose (-)