EBK BROCK BIOLOGY OF MICROORGANISMS
15th Edition
ISBN: 8220103633352
Author: Stahl
Publisher: PEARSON
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Chapter 3, Problem 2AQ
Summary Introduction
To explain:
The following observation in light of the redox tower: Escherichia coli cells fermenting glucose grow faster when nitrate (NO3-) is supplied to the culture and then grow even faster when the culture is aerated.
Concept introduction:
An oxidation is a process in which electrons are removed from a substance and in the reduction process; electrons are added to the substance. The combination of these processes is termed as redox (
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Below is shown a growth curve for an E. coli culture. As indicated, the culture was incubated in the absence of a carbon source for 2 hours until Glucose and Lactose were added; Glucose was used up after 5 hours, and Lactose was used up after 8 hours. During the time-course, you take four samples, labeled A-D, after 1, 3, 7 and 9 hours, respectively, as indicated under the graph. Assuming there is cAMP present at t=0, for each sample identify whether CAP and/or the Lac Repressor would be bound to the DNA, and explain why.
Below is shown a growth curve for an E. coli culture. As indicated, the culture was incubated in the absence of a carbon source for 2 hours until Glucose and Lactose were added; Glucose was used up after 5 hours, and Lactose was used up after 8 hours. During the time-course, you take four samples, labeled A-D, after 1, 3, 7 and 9 hours, respectively, as indicated under the graph. Assuming there is cAMP present at t=0, for each sample identify whether CAP and/or the Lac Repressor would be bound to the DNA, and explain why.
Chapter 3 Solutions
EBK BROCK BIOLOGY OF MICROORGANISMS
Ch. 3.1 - Which four chemical elements make up the bulk of a...Ch. 3.1 - Which two classes of macromolecules contain most...Ch. 3.1 - Differentiate between trace metals and growth...Ch. 3.1 - Prob. 1CRCh. 3.2 - Compare and contrast simple transporters, the...Ch. 3.2 - Prob. 2MQCh. 3.2 - Cells of Escherichia coli transport lactose via...Ch. 3.3 - Prob. 1MQCh. 3.3 - Prob. 2MQCh. 3.3 - Prob. 1CR
Ch. 3.4 - What is free energy?Ch. 3.4 - Prob. 2MQCh. 3.4 - Using Table 3.2, calculate G0 for the reaction...Ch. 3.4 - Prob. 1CRCh. 3.5 - Prob. 1MQCh. 3.5 - Prob. 2MQCh. 3.5 - Prob. 3MQCh. 3.5 - Prob. 1CRCh. 3.6 - Prob. 1MQCh. 3.6 - Prob. 2MQCh. 3.6 - Prob. 3MQCh. 3.6 - Prob. 1CRCh. 3.7 - How much free energy is released when ATP is...Ch. 3.7 - Prob. 2MQCh. 3.7 - Prob. 3MQCh. 3.7 - Prob. 1CRCh. 3.8 - Which reactions in glycolysis are redox steps?Ch. 3.8 - Prob. 2MQCh. 3.8 - Prob. 3MQCh. 3.8 - How is ATP made in fermentation and in...Ch. 3.9 - How many molecules of CO2, NADH, and FADH2 are...Ch. 3.9 - What two major roles do the citric acid cycle and...Ch. 3.9 - Why is the glyoxylate cycle necessary for growth...Ch. 3.9 - Prob. 1CRCh. 3.10 - Prob. 1MQCh. 3.10 - Which electron carriers described in this section...Ch. 3.10 - List some of the key electron carriers found in...Ch. 3.11 - How do electron transport reactions generate the...Ch. 3.11 - How much energy is released per NADH oxidized...Ch. 3.11 - What structure in the cell links the proton motive...Ch. 3.11 - Prob. 1CRCh. 3.12 - Prob. 1MQCh. 3.12 - Prob. 2MQCh. 3.12 - Prob. 3MQCh. 3.12 - What is the major difference between aerobic...Ch. 3.13 - What form of activated glucose is used in the...Ch. 3.13 - Prob. 2MQCh. 3.13 - What functions does the pentose phosphate pathway...Ch. 3.13 - What is the importance of the enzyme...Ch. 3.14 - Prob. 1MQCh. 3.14 - List the steps required for the cell to...Ch. 3.14 - Which nitrogen bases are purines and which are...Ch. 3.14 - Prob. 1CRCh. 3.15 - Prob. 1MQCh. 3.15 - Prob. 2MQCh. 3.15 - Describe the process by which a fatty acid such as...Ch. 3 - Using the data of Figure 3.10, predict the...Ch. 3 - Prob. 2AQ
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