The lactose (lac) operon in E. coli is a gene that helps break down lactose in the cell. If there is no lactose present, the operon is repressed. In 3-5 sentences, explain how the lac operon is used and repressed in cells. Use the following words in your response: operon, operator, repressor, RNA polymerase, and transcribe/transcription

Answer 1

The lac operon in E. coli is a group of genes responsible for the metabolism of lactose. When lactose is not present, a repressor protein binds to the operator region of the operon, preventing RNA polymerase from attaching and transcribing the genes necessary for lactose metabolism. In the presence of lactose, the lactose molecules bind to the repressor, causing it to change shape and detach from the operator. This allows RNA polymerase to access the promoter and transcribe the genes in the operon, leading to the production of enzymes that break down lactose.