题目
题目

BIOL_2004_81774_202509 Genetics Test 4- Requires Respondus LockDown Browser

单项选择题

When tryptophan concentrations are high in Escherichia coli, what happens?

选项
A.The tryptophan synthesis genes are not transcribed.
B.all of the above
C.Tryptophan binds the repressor so that it can repress trp operon transcription.
D.Attenuation causes premature termination of transcription.
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思路分析
The question asks what happens when tryptophan concentrations are high in Escherichia coli, focusing on the regulation of the trp operon. Option 1: 'The tryptophan synthesis genes are not transcribed.' With high tryptophan, the operon is repressed, so transcription of the biosynthetic genes i......Login to view full explanation

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