Biology: Life on Earth
10th Edition
ISBN: 9780321729712
Author: Gerald Audesirk, Teresa Audesirk, Bruce E. Byers
Publisher: Benjamin Cummings
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Chapter 1, Problem 3AC
Review Alexander Fleming's experiment that led to the discovery of penicillin. What would be an appropriate control for the experiment in which Fleming applied filtered medium from a Penicillium culture to plates of bacteria?
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Attached below is the study about the effects of handwashing and the effectiveness of soap against bacteria. What conclusions can be generated from this result?
A
C
before washing hands
10 second hand wash
B
D
hot water only rinse
30 second hand wash
Figure 8: Agar plates with bacteria A) before washing hands B) after rinsing hands in hot water C) After washing
hands with soap for 10 seconds and D) after washing hands for 30 seconds. Images show that the number of
bacteria on the plate are not greatly reduced after a hot water rinse or 10 second handwash but bacterial levels are
reduced after a proper hand wash for 30 seconds.
The Kirby-Bauer test examines the effectiveness of antibiotics and disinfectants or antiseptics on separately plated bacteria. Which of the following Zones of Inhibition (ZOI) measurements on a plate of Klebsiella pneumoniae shows the strongest inhibition of the bacterium's growth?
a) Penicillin, 7 mm ZOI
b) Actinomycin, 9 mm ZOI
c) Tetracycline, 26 mm ZOI
d) Chloramphenicol 2 mm ZOI
e) Streptomycin, 23 mm ZOI
What is the purpose of staining bacteria? What is the purpose of collecting bacteria from different sources and staining them. What can you learn from this type of experiment?
Chapter 1 Solutions
Biology: Life on Earth
Ch. 1 - 1. Organisms respond to _______. Organisms acquire...Ch. 1 - Prob. 2FTBCh. 1 - Prob. 3FTBCh. 1 - An important scientific theory that explains why...Ch. 1 - 5. The molecule that guides the construction and...Ch. 1 - What properties are shared by all forms of life?Ch. 1 - Why do organisms require energy? Where does the...Ch. 1 - Define evolution, and explain the three natural...Ch. 1 - Prob. 4RQCh. 1 - 5. What are some differences between prokaryotic...
Ch. 1 - 6. What basic principles underlie scientific...Ch. 1 - Which kingdom(s) are heterotrophic? Which are...Ch. 1 - What is the difference between a scientific theory...Ch. 1 - 8. What factors did Rudi control for in his open...Ch. 1 - Prob. 10RQCh. 1 - List the steps in the scientific method with a...Ch. 1 - What properties of life does your computer...Ch. 1 - 2. How would this textbook's definition of life...Ch. 1 - 3. Review Alexander Fleming's experiment that led...Ch. 1 - 4. Explain an instance in which your own...Ch. 1 - Provide an example (different from that in the...
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