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Home Q & A Board Biology-Related Homework Help Genetics and Developmental Biology
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Yeah.Yeah. Yeah.Yeah.
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3 years ago
Which of the following best explains why E. coli shuts down the trp operon if tryptophan is available in the environment?


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It does not shut down the trp operon, it only lowers the level of trp operon activity.


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The trp operon encodes genes that export tryptophan from the cell; if tryptophan already occurs in the environment, further export is not necessary.


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Synthesizing an amino acid takes energy, so it is a waste of energy to make something that is already available.


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Environmental tryptophan is of higher quality than what the E. coli can make itself.
Textbook 
Biology: Exploring the Diversity of Life

Biology: Exploring the Diversity of Life


Edition: 4th
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Jessie19950607Jessie19950607
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Yeah.Yeah. Author
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3 years ago
Just got PERFECT on my quiz
Mkersey12
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Yesterday
Good timing, thanks!
Harvinder
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2 hours ago
Thanks
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