operon question

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operon question

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bioguy
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04/12/08 - 05:02 PM

A bacterial operon has two genes and one regulatory site. Experiments have determined the transcribed and non-transcribed regions of the operon. Deletion of 10 bp of the non-transcribed region resulted in the genes be actively transcribed irrespective of the presence or absence of sugar. What is the deleted region?

A. Activator site

B. Operator site

C. Repressor site

D. Activator gene

Tiff
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04/12/08 - 05:36 PM

bioguy
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04/12/08 - 11:42 PM

exactly, i thought the same too. but its not!!! can anyone think otherwise????

Tiff
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04/13/08 - 02:17 PM

bioguy wrote:
exactly, i thought the same too. but its not!!! can anyone think otherwise????

OK. Then the only other thing I can think of is the B - the operator site. In review the question, the deleted region is the non-transcribed region. Transcription takes place after the operator region. The operator site is where repressor proteins and activator proteins bind.

sigh
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04/13/08 - 06:22 PM

B
In the question we see "deletion of non-transcribed region" so it can not be repressor because repressor is transcribed as protein...

bioguy
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04/13/08 - 09:17 PM

you guys got it nod

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