The correct answer is: B) continuous transcription of the structural gene controlled by that regulator
A regulatory gene is gene that encodes for a protein, such as a repressor (or activators) that controls the transcription of another gene or group of genes.
The regulatory gene of a repressible operon encodes for the repressor that inhibits gene transcription. So, when that repressor isn’t active, transcription occurs continuously.
Answer:
The food type changes in a given environment, then the amount of each type of bird beak will changes as birds with beaks more suited to the available food will consume more successfully over time. The independent variable of the lab is the type of food that is available to the birds.
It has two layers.
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