Laboratory Experiments in Microbiology (11th Edition)
11th Edition
ISBN: 9780321994936
Author: Ted R. Johnson, Christine L. Case
Publisher: PEARSON
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Textbook Question
Chapter 7, Problem 4Q
Which step can you omit without affecting determination of the Gram reaction?
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Suppose your Professor handed you a test tube with 2.0mL of E.coli broth culture and told you to make a 10-1 dilution of the ENTIRE culture. Explain how you would do this.
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Which plate contains an unsupplemented minimal medium? [Select]
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plate 2
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plate 3
plate 7
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The following data were obtained by incubating gram-positive bacteria in nutrient medium +
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a. Table 7.3, which disinfectant is the most effective at stopping bacterial growth?
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b. In Table 7.3, which disinfectant was bactericidal? How can you tell?
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Table 7.3
K.O.
Subculture
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Initial
Subculture
Initial
1:16
1:32
1:64
1:128
Mortum
Sterl
Dilution
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Subculture
Initial
Subculture
1:16
1:32
1:64
1:128
Chapter 7 Solutions
Laboratory Experiments in Microbiology (11th Edition)
Ch. 7 - Why do gram-positive cells more than 24 hours old...Ch. 7 - Can iodine be added before the primary stain in a...Ch. 7 - Prob. 3QCh. 7 - Which step can you omit without affecting...Ch. 7 - Suppose you performed a Gram stain on a sample...Ch. 7 - Prob. 2CTCh. 7 - Human cells can be stained with crystal violet and...Ch. 7 - Considering that it isnt possible to identity...
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