In bacterial cells, the tryptophan operon encodes the genes needed to synthesize tryptophan. What happens when the concentration of tryptophan inside a cell is high?
a. It activates the tryptophan repressor, allowing transcription of the tryptophan operon.
b. It inactivates the tryptophan repressor, allowing transcription of the tryptophan operon.
c. It activates the tryptophan repressor, which shuts down expression of the tryptophan operon.
d. It inactivates the tryptophan repressor, which shuts down the tryptophan operon.
e. It activates the tryptophan repressor, which breaks down excess tryptophan.
Ans: c. It activates the tryptophan repressor, which shuts down expression of the tryptophan operon.
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