What is the default state of a gene whose expression is controlled by a repressor? An activator?
What will be an ideal response?
Ans: The default state for a gene whose expression is controlled by a repressor is continuous expression via recognition of its promoter by RNA polymerase. The presence of the repressor is required to turn the gene off. The default state for a gene whose expression is controlled by an activator is to remain unexpressed. The presence of the activator is required to turn the gene on.
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