Practical Lab Final Images Flashcards
1) What media is this? What colors can it be?
2) What bacteria is this and what color is it supposed to look like?
1) EMB; media color ranges from yellow to red
2) E. aerogenes; larger colonies, pinkish to brown center
1) What media is this?
2) What bacteria is this? What color is it supposed to be?
1) EMB
2) E. coli; dark centered colonies with clear edges and tends to have a metallic sheen
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) BA (blood agar)
2) Alpha strep; dark brown due to alpha hemolysis
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) BA
2) SA; clearing has occurred and media has brightened due to beta hemolysis
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) BA
2) S. epi; nothing has occurred in the media due to gamma hemolysis
1) What media is this?
2) What bacteria is this? What has it done to the media?
1) MSA
2) S. epi; media remains pink because no fermentation occurred
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) MSA
2) S. aureus; the phenol red turned yellow due to fermentation (and decreased pH)
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) MAC
2) E.coli; it turned the neutral red indicator red since acids were produced by lactose fermentation. Growth was inhibited by bile salts.
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) MAC
2) S. ent (Salmonella enteritidis); the bacteria grew well, but the media remained yellow because no fermentation occurred.
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) MAC
2) S. son (Shigella sonnei); the bacteria grew well, but the media remained yellow because no fermentation occurred.
1) What media is this?
2) What bacteria is this? What has it done to the media and why?
1) Salmonella-Shigella Agar (SS)
2) E. coli; growth was limited by bile salts but turned the agar red due to lactose fermentation decreasing the pH (neutral red indicator).
1) What media is this?
2) What bacteria is this? What has it done with the media?
1) SS
2) S. enteritidis; transparent colonies with dark centers due to H2S formation
1) What media is this?
2) What bacteria is this? What has it done to the media?
1) SS
2) Shigella sonnei; has reddish pink colonies but has not changed the media
1) What test is this?
2) What did the bacteria do in the media?
3) What bacteria give this result?
1) TSI
2) A/A: Anaerobic fermentation of sucrose/lactose and produced gas; no H2S formation.
3) E. coli, K. pneumoniae, E. aerogenes
1) What test is this?
2) What did the bacteria do in the media?
3) What bacteria give this result?
1) TSI
2) K/A: Aerobic (glucose) and anaerobic (sucrose/lactose) fermentation and gas formation; no H2S formation
3) E. aerogenes
1) What test is this?
2) What did the bacteria do in the media?
3) What bacteria give this result?
1) TSI
2) A/A: Anaerobic fermentation of sucrose/lactose and produced gas; H2S formation occurred.
3) Citrobacter freundii (CF), Proteus vulgaris (PV)
1) What test is this?
2) What did the bacteria do in the media?
3) What bacteria give this result?
1) TSI
2) K/K aerobic respiration (glucose) only; no H2S or gas formation
3) B. subtilis; CX
1) What test is this?
2) What did the bacteria do in the red tube?
3) What did the bacteria do in the yellow tubes?
1) Phenol red sugars (glu, lac, man, suc, xyl)
2) Nothing; stayed red and no gas formed
3) Ferment the sugar and produce acid, turning phenol red yellow.
1) What test is this?
2) What did the bacteria do in the red tube?
3) What did the bacteria do in the yellow tubes?
1) Phenol red sugars
2) Nothing; stayed red and no gas was produced
3) Ferment the sugar and produce acid and gas, turning phenol red yellow and adding gas to the Durham tubes.
1) What test is this?
2) What did bacteria do in the top tube? What bacteria do(es) this?
3) What did bacteria do in the middle tube? What bacteria do(es) this?
4) What did bacteria do in the bottom tube? What bacteria do(es) this?
1) Litmus milk (LM)
2) Top: Lactose fermentation occurred (white); no clearing and clotting. B. cereus.
3) Middle: No fermentation occurred, but clearing and clotting occurred. B. subtilis.
4) Bottom: No fermentation, clearing, or clotting occurred. S. sonnei, E. faecalis, Cx.
1) What test is this?
2) What did bacteria do in the top and bottom tubes? What bacteria do(es) this?
3) What did bacteria do in the middle tube? What bacteria do(es) this?
1) Litmus milk (LM)
2) Top and bottom: Lactose fermentation occurred (white); no clearing or clotting. E. aerogenes, E. coli, K. pneumoniae, S. aureus
3) Middle: No fermentation, clearing, or clotting. S. sonnei, E. faecalis, Cx.
Which bacteria does slow fermentation and gives a purple LM result?
S. enteritidis
1) What test is this?
2) What did bacteria do in the top tube? What species do this?
3) What did bacteria do in the bottom tube? What species do this?
1) Phenylalanine deaminase (PHE)
2) Nothing occurred. E. coli, S. mitis, E. aerogenes.
3) Bacteria has phenylalanine deaminase, and reduced phenylalanine into PPA, which reacted with ferric chloride and turned dark green. P. vulgaris.
1) What test is this?
2) What bacteria is in the plate on the left? Describe the colony morphology.
3) What bacteria is in the right? Describe the colony morphology
1) Mitis-Salivarius (MS)
2) Proteus vulgaris; has large mucoid colonies but reduced growth (because of tellurite in media)
3) E. faecalis; dark blue to black shiny colonies (S. mitis is the same)
1) What test is this?
2) What bacteria is this? Describe the colony morphology
3) What enzyme is present in bacteria that can grow on this media?
1) MS
2) Alpha strep; has small colonies with abundant growth (streptococcus grows best on MS and is most resistant to crystal violet).
3) Saccharase (invertase)
1) What test is this?
2) What did the bacteria do in the entirely yellow tube? What species does this?
3) What did the bacteria do in the tube with red? What species does this?
1) Sulfide Indole Motility (SIM)
2) No motility, no H2S formation, no indole formation. E. aerogenes.
3) Indole formation occurred (red); no motility or H2S formation. E. coli.
1) What test is this?
2) What did the bacteria do in the top tube? What species does this?
3) What did the bacteria do in the bottom tube? What species does this?
1) SIM
2) H2S formation and motility occurred; no indole production. C. freundii.
3) Indole production (red), H2S formation, and motility occurred. Proteus vulgaris.
1) What test is this?
2) Which tube is positive? Give an example of a species that does is. What occurs on the media?
3) Which is negative? Give an example of a species with this result.
1) Citrate
2) The bright blue tube: E. aerogenes grows on citrate and releases ammonium salts, increasing pH and turning bromothymol blue blue.
3) The green tube: E. coli.
1) What test is this?
2) Which tube is positive? Give an example of a species that does this. What occurs on the media?
3) Which is negative? Give an example of a species with this result.
1) Methyl red.
2) The red tube is positive; E. coli does mixed-acid fermentation and lowers pH, causing methyl red to turn red.
3) The yellow tube is negative; E. aerogenes.
1) What test is this?
2) Which tube is positive? Give an example of a species that does this. What occurs on the media?
3) Which is negative? Give an example of a species with this result.
1) Voges-Proskauer (VP)
2) The tube on the right (dark red/ purple); E. aerogenes performs alcoholic fermentation and produces acetylmethylcarbinol, which reacts with VP-A and VP-B.
3) The tube on the left (yellow); E. coli.
1) What test is this?
2) Which tube is positive? What occurs on the media?
3) Which is negative?
1) ONPG
2) The tube on the right (yellow) is positive; the culture’s B-galactosidase allowed for ONPG to be broken down (via lactose fermentation) into nitrophenol (yellow) and sugar.
3) The tube on the left (clear).
1) What test is this?
2) Which tube is positive? Give an example of a species that does this. What occurs in the media?
3) Which is negative? Give an example of a species with this result.
1) Coagulase
2) The tube on the left (contains a clot); S. aureus.
3) The tube on the right; S. epi.
1) What test is this?
2) Is a positive or negative example?
3) What happens during this test?
4) What species is negative for this test?
1) Catalase
2) A positive example (bubbles/ fizzing).
3) The enzyme catalase degrades toxic H2O2
4) Negative: Streptococci genus
1) What test is this?
2) What does the test tube on the far left indicate?
3) What does the red test tube in the middle indicate?
4) What does the orange test tube on the right indicate?
5) What does the red test tube on the far right indicate?
1) NO3 (Nitrate)
2) Colorless before zinc: Proceed with zinc test.
3) Red before zinc: Nitrate reductase and NO2 are present
4) No change after zinc: Denitrification occurred; N2 present.
5) Red after zinc: Nothing has occurred; NO3 still present
1) What test is this?
2) Which of the clear petri dishes is positive? Which is negative?
3) What side of the green petri dish is positive and which is negative? What is used to make it green?
1) DNase
2) Right one (zone of clearing around culture) is positive, left one is negative.
3) The right side (zone of clearing around culture) is positive, the left side is negative. Methyl green is used.
1) What test is this?
2) Which tube is positive? What occurs in this tube?
3) Which tube is negative?
1) Nutrient Gelatin/ Gelatinase
2) The tube on top is positive; it remained liquid even when cold due to gelatinase breaking down gelatin.
3) The tube on the bottom is negative (becomes solid)
1) What test is this?
2) Which plate is positive? What occurs on this plate?
3) Which plate is negative?
1) Nutrient starch (amylase)
2) The one on the left (zone of clearing) because the starch that has reacted with iodine has been broken down by amylase.
3) The one on the right (all dark purple)
1) What test is this?
2) Which tube is positive? What occured in this tube?
3) Which tube is negative?
1) Urea
2) The pink tube; urease broke down urea into ammonia and CO2, which increased pH and caused phenol red to turn pink/purple.
3) The orange tube (stayed orange)
1) What test is this?
2) Which tube is positive? What occured in this tube?
3) Which tube is negative?
1) Lysine Decarboxylase (LYS)
2) The purple tube; after glucose fermentation, lysine is broken down by lysine decarboxylase, which increases pH and causes the bromocresol purple to turn purple.
3) The yellow tube; glucose was fermented and the tube stayed yellow (acidic).
