Microbiology: An Introduction
12th Edition
ISBN: 9780321929150
Author: Gerard J. Tortora, Berdell R. Funke, Christine L. Case
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 3CAE
The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were incubated aerobically for 48 hours at 37°C.
| Bacteria per ml Saliva | ||
| Before UsingMouthwash | After UsingMouthwash | |
| Mouthwash 1 | 13.1 × 106 | 10.9 × 106 |
| Mouthwash 2 | 11.7 × 106 | 14.2 × 105 |
| Mouthwash 3 | 9.3 × 105 | 7.7 × 105 |
What can you conclude from these data? Did all the bacteria present in each saliva sample grow?
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The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were inoculated aerobically for 48 hours at 37°C.
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Chapter 6 Solutions
Microbiology: An Introduction
Ch. 6 - Prob. 1RCh. 6 - Prob. 2RCh. 6 - Prob. 3RCh. 6 - Seven methods of measuring microbial growth were...Ch. 6 - By deep-freezing, bacteria can be stored without...Ch. 6 - A pastry chef accidentally inoculated a cream pie...Ch. 6 - Nitrogen and phosphorus added to beaches following...Ch. 6 - Differentiate complex and chemically defined...Ch. 6 - DRAW IT Draw the following growth curves for E....Ch. 6 - NAME IT A prokaryotic cell hitched a ride to Earth...
Ch. 6 - Two culture media were inoculated with four...Ch. 6 - Two culture media were inoculated with four...Ch. 6 - Use the following graph to answer questions 3 and...Ch. 6 - Use the following graph to answer questions 3 and...Ch. 6 - Assume you inoculated 100 facultatively anaerobic...Ch. 6 - The term trace elements refers to a. the elements...Ch. 6 - Which one of the following temperatures would most...Ch. 6 - Which of the following is not a characteristic of...Ch. 6 - Which of the following types of media would not be...Ch. 6 - An organism that has peroxidase and superoxide...Ch. 6 - E. coli was incubated with aeration in a nutrient...Ch. 6 - Clostridium and Streptococcus are both...Ch. 6 - Most laboratory media contain a fermentable...Ch. 6 - Flask A contains yeast cells in glucose-minimal...Ch. 6 - Clinical Applications and Evaluation 1. Assume...Ch. 6 - Heat lamps are commonly used to maintain foods at...Ch. 6 - The number of bacteria in saliva samples was...
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