Study Guide for Campbell Biology
11th Edition
ISBN: 9780134443775
Author: Lisa A. Urry, Michael L. Cain, Steven A. Wasserman, Peter V. Minorsky, Jane B. Reece, Martha R. Taylor, Michael A. Pollock
Publisher: PEARSON
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Textbook Question
Chapter 27, Problem 13TYK
O157:H7, a pathogenic strain of E. coli, has over 1,000 genes that are not present in the harmless strain K-12. Many of these genes are associated with phage DNA in the bacterial chromosome. These observations suggest that
- a. this virulent strain has many more R plasmids than does the harmless strain and is resistant to almost all antibiotics.
- b. at least some of these genes were acquired through phage-mediated horizontal gene transfer.
- c. virulence genes appear to have been acquired through conjugation with K-12.
- d. all of the above are correct.
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The linear dsDNA genome of λ binds on the LamB receptor of E. Coli and conducts a normal lysogenic cycle. Exposure to stress will cause the excision of λ prophage from the E. Coli genome. The excised λ genome is then replicated, packaged, and released from the cell as mature λ phage particles and ready to infect other bacterial cells. Among λ phage particles,the transducing phage mediates a specific type of recombination. Understand this scenario and answer the following questions.
1. What are the basic requirements for the insertion of λ into the E. Coli genome? 2. What special features are found in the λ insertion site? 3. What type of recombination occurs with λ insertion in the E. Coli genome? 4. How you will differentiate λ transducing phage from normal λ phage? 5. What exclusive mechanism λ phage utilizes for recombination?
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Chapter 27 Solutions
Study Guide for Campbell Biology
Ch. 27 - Fill in the following table with brief...Ch. 27 - Complete the following concept map that summarizes...Ch. 27 - This is a micrograph of the cyanobacterium...Ch. 27 - Prob. 4IQCh. 27 - Prob. 5IQCh. 27 - One might think of prokaryotes as primitive,...Ch. 27 - Prob. 2SYKCh. 27 - Prob. 1TYKFCh. 27 - __________ region in which the prokaryotic...Ch. 27 - __________ common staining technique that...
Ch. 27 - Prob. 4TYKFCh. 27 - Prob. 5TYKFCh. 27 - Prob. 6TYKFCh. 27 - Prob. 7TYKFCh. 27 - Prob. 8TYKFCh. 27 - ___________ use of organisms to remove...Ch. 27 - __________type of respiration that uses molecules...Ch. 27 - The Gram stain distinguishes among bacteria based...Ch. 27 - Prob. 2TYKCh. 27 - Some prokaryotes have specialized internal...Ch. 27 - Prob. 4TYKCh. 27 - Prob. 5TYKCh. 27 - Prob. 6TYKCh. 27 - Prob. 7TYKCh. 27 - Prob. 8TYKCh. 27 - Prob. 9TYKCh. 27 - Prob. 10TYKCh. 27 - Which of the following statements accurately...Ch. 27 - Prob. 12TYKCh. 27 - O157:H7, a pathogenic strain of E. coli, has over...
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