In the presence of abundant tryptophan:
A)the attenuator stem-loop structure forms,allowing transcription to continue.
B)the attenuator stem-loop structure forms,terminating transcription.
C)the preemptor stem-loop structure forms,allowing transcription to continue.
D)the preemptor stem-loop structure forms,terminating transcription.
E)None of the answer options are correct.

Question

Quizplus · Accepted Answer

In the presence of abundant tryptophan, the attenuator stem-loop structure forms, which causes the termination of transcription. This is a mechanism of gene regulation in bacteria, such as in the trp operon of E. coli, where high levels of tryptophan promote the formation of a transcriptional terminator structure, effectively stopping the synthesis of enzymes involved in tryptophan synthesis.

In the Presence of Abundant Tryptophan