Besides the negative regulation of repressor protein, what’s the unique regulation of tryptophan operon:()
A. Repression
B. Induction
C. Attenuation
D. Catabolite repression
E. Anti-termination
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Which of the following conditions lead to the highest expression of tryptophan operon:()
A. High concentration of Trp while low concentration of other amino acids.
B. High concentration of other amino acids while low concentration of Trp.
C. Both Trp and other amino acids are high concentration.
D. Both Trp and other amino acids are low concentration.
Tryptophan operon belongs to:()
A. negative regulation-induction system
B. negative regulation-repression system
C. positive regulation-induction system
D. positive regulation-repression system
An operon containing three structural genes can be regulated by negative transcriptional regulation, then which of the following statements is true:()
A. The operon contains three binding sites for repressor proteins.
B. The operon contains three promotors.
C. The inhibitor of the regulator protein of the operon would inhibit the transcription of structural genes.
D. The regulator gene of the operon can be located downstream of this operon.
The role of glucose in catabolite repression is:()
A. Improving the activity of adenylate cyclase, to increase the concentration of intracellular cAMP.
B. Inhibiting the activity of adenylate cyclase, to decrease the concentration of intracellular cAMP.
C. Improving the activity of phosphodiesterase, to increase the concentration of intracellular cAMP.
D. Inhibiting the activity of phosphodiesterase, to decrease the concentration of intracellular cAMP.
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