Question

An amino acid is synthesized by the prokaryote, E. coli. The genes for the enzymes are responsible for synthesizing this amino acid are encoded in an operon. The operon is regulated by a reperssor. When the amino acid binds to the repressor, the repressor changes shape so it can bind to the operator. Which of the following statements is true?
A. When levels of the amino acid are high, it binds to the repressor, allowing synthesis of this amino acid to proceed.
B. When levels of the amino acid are low, it binds to the repressor, allowing synthesis of this amino to proceed.

Answer 1

The answer is when levels of the amino acid are high, it binds to the repressor, ending the synthesis of this amino acid