Examine the following theoretical operon (gen) in E. coli which contains structural genes (genC, genB, genA) that are involved in amino acid biosynthesis. The gen operon also includes the gene encoding for the regulator molecule within it. When the amino acid that this operon helps synthesize is present, it binds to the regulator forming a complex which can bind to the operator region. Assume that the regulator molecule only binds to the operator in the presence of the amino acid. Promoter || Operator genC genB gen operon Regulator genA Question 3 Assume each gene in the gen operon has its own start and stop codons. How would a nonsense mutation in the genB region influence the expression of the gen operon in the absence of the amino acid? A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information Question 3 Assume each gene in the gen operon has its own start and stop codons. How could a base substitution mutation in the operator region influence the expression of the gen operon in the abundance of the amino acid? A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information

Examine the following theoretical operon (gen) in E. coli which contains structural genes (genC, genB, genA) that are involved in amino acid biosynthesis. The gen operon also includes the gene encoding for the regulator molecule within it. When the amino acid that this operon helps synthesize is present, it binds to the regulator forming a complex which can bind to the operator region. Assume that the regulator molecule only binds to the operator in the presence of the amino acid. Promoter || Operator genC genB gen operon Regulator genA Question 3 Assume each gene in the gen operon has its own start and stop codons. How would a nonsense mutation in the genB region influence the expression of the gen operon in the absence of the amino acid? A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information Question 3 Assume each gene in the gen operon has its own start and stop codons. How could a base substitution mutation in the operator region influence the expression of the gen operon in the abundance of the amino acid? A. Gain of function B. Loss of function C. Null D. Silent E. Insufficient information

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

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