Chapter 18-19

Last update by mayurcooled on 04/23/2014
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The tryptophan operon is a repressible operon that is



A. permanently turned on. B. turned off only when glucose is present in the growth medium. C. turned on only when tryptophan is present in the growth medium. D. turned on only when glucose is present in the growth medium. E. turned off whenever tryptophan is added to the growth medium.

Answer:
E. turned off whenever tryptophan is added to the growth medium.

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