Nester's Microbiology: A Human Perspective
9th Edition
ISBN: 9781259709999
Author: Denise G. Anderson Lecturer, Sarah Salm, Deborah Allen
Publisher: McGraw-Hill Education
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Chapter 4, Problem 10SA
Summary Introduction
To review:
The best method to determine the number of microorganisms in lake water using both a direct microscopic count and a plate count.
Introduction:
The direct microscopic count and the plate count are the measuring techniques for observing the microbial growth of the microorganisms in a sample with the help of a microscope. These techniques measure the mass and number of the cells, and constituents of the cellthat is proportional to cell number.
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the scientist is studying the effect of water purification tablets on the creek water in her local area. She collected several different 2 L samples from a creek. For each sample, she measured the number of coliform group bacteria colonies in the water initially, and then added a water purification tablet and measured the number of coliform group bacteria colonies over time. She found that the following equation was a good fit to the data:
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Chapter 4 Solutions
Nester's Microbiology: A Human Perspective
Ch. 4 - Describe a detrimental and a beneficial effect of...Ch. 4 - Define a pure culture.Ch. 4 - Prob. 3SACh. 4 - Explain how the environment of a colony differs...Ch. 4 - Prob. 5SACh. 4 - Why would botulism be a concern with canned foods?Ch. 4 - Explain why O2-containing atmospheres kill some...Ch. 4 - Explain why photoautotrophs are primary producers.Ch. 4 - Distinguish between a selective medium and a...Ch. 4 - Prob. 10SA
Ch. 4 - Prob. 1MCCh. 4 - Compared with their growth in the laboratory,...Ch. 4 -
3. Cells are most sensitive to penicillin during...Ch. 4 - Which best describes the intestinal tract? a) An...Ch. 4 - E. coli, a facultative anaerobe, is grown for 24...Ch. 4 - The generation time of a bacterium was measured at...Ch. 4 - Which of the following is false? a)E. coli grows...Ch. 4 -
8. If the pH indicator were left out of MacConkey...Ch. 4 -
9. A soil sample is placed in liquid and the...Ch. 4 -
10. If the concentration of E. coli in a broth is...Ch. 4 -
1. You are a microbiologist working for a...Ch. 4 - High-performance boat manufacturers know that...Ch. 4 - This figure shows a growth curve plotted on a...Ch. 4 - Prob. 2CT
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