Microbiology

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Microbiology Practical Review
Patricia Sidelsky - 2004
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How do you make a smear from a solid culture and
a broth culture?
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Gram Stain
What is the primary stain ?
Crystal violet
What is the counterstain?
Saffranin
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Gram positive organisms stain_____________because_
__________________ Gram negative organisms stain
_____________ because_____________________________
_
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The most common errors in gram staining?

• Decolorizer
• Fixing
• Timing
• Smear

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What is the importance of using iodine in the
Gram stain?
Iodine is the mordant . It helps the crystal
violet stick to the gram positive cell wall
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Morphology and Gram stain?
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Gram stain
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Blood agar plates
What are the types of hemolysis?
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This is selective for
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What organisms produces these results?Why?
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These results are caused by?
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EMB stands for
What do these results show?
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Differential and selective ?
What agar?
Selects for? Differentiates between?
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Sugar fermentation
Explain the results in tube 3A
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What is the agar used in this test?
Explain the results in tube 4
Explain the results in tube 2
Explain the results in tube 5
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What enzyme causes the liquefaction of gelatin?
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What organism tests positive ?
What causes the pink color?
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What enzyme changes the color from green to blue?
Organisms that have a positive test use what for
their source of carbon?
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What reagent is added to these tubes ?
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This test is used to differentiate between?
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This experiment is used to test for ..
What type of agar?
Which is the positive result ?
What is this reagent?
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Sensitive( susceptible) or resistant?
Type of agar ?????????
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Test for what kind of organisms ?
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The name of the test is ..
What reagent is added to the slant?
Which organism tests positive?
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What bacterium has a positive test?
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What two organisms are catalase ?
What compound is broken down in the above
reaction? What gas is produced?
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What bacterium ferments mannitol and has a high
tolerance for salt? Do any other organisms
tolerate salt?