Answer :
When there is low lactose in the system, the repressor will bind to the active site preventing transcription of protein. When there is high lactose, it will bind with the repressor preventing it from binding to the active site. Thus, transcription of protein will occur.
Answer:
When the lactose in absent then under such a situation the Lac repressor protein bind to lac operator and prevents the transcription of lac Z, lacY and lac A gene by the RNA polymerase. When the lactose is present then the allolactose binds to lac repressor and prevent repressor binding and the lac operon is called inducible.
When the concentration of lactose is high then at that time the lac operon is turned on and CAP is bind and bacteria is able to use lactose. When the concentration of lactose is low inside the cell under such a situation the lac operon is shut off and bacteria are not able to use lactose