1. The B-galactosidase gene of the lac operon is expressed at high level when which combination of following conditions is met? A. Select one answer for each of the following. Lactose concentration low high Lac Repressor Protein Inactive Active CAMP concentration low high Catabolite Activator Protein (CAP) Inactive Active B. Describe a mutation in a noncoding regulatory element that would result in constitutively high ß-galactosidase expression in the presence of both low glucose and low lactose. Explain its effect on gene regulation.

1. The B-galactosidase gene of the lac operon is expressed at high level when which combination of following conditions is met? A. Select one answer for each of the following. Lactose concentration low high Lac Repressor Protein Inactive Active CAMP concentration low high Catabolite Activator Protein (CAP) Inactive Active B. Describe a mutation in a noncoding regulatory element that would result in constitutively high ß-galactosidase expression in the presence of both low glucose and low lactose. Explain its effect on gene regulation.

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Description: 1. The B-galactosidase gene of the lac operon is expressed at high level when which combinationof following conditions is met?A. Select one answer for each of the following.Lactose concentrationlowhighLac Repressor ProteinInactiveActiveCAMP concentr

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter16: Regulation Of Gene Expression

Section: Chapter Questions

Problem 2TYK: For the E. coli lac operon, when lactose is present: a. and glucose is absent, cAMP binds and...

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1. Assuming that the level of glucose is low, a mutation in the repressor associated with the lac operon of E. coli which prevents binding of the repressor to lactose should result in: a. constitutive expression of the lac operon genes b. lack of expression or refuced expression of the lac operon genes under all circumstances c. expression of the genes only when lactose is present d. expression of the genes only when lactose is absent e. lack of expression of the lac operon genes, resulting in an increase in lactose production
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