3.(10) Regulation of gene expression in prokaryote usually occurs at the transcription level, and the two major mechanisms are and 4.(15)What are the mechanisms that ensure the structure genes of lac operon are only transcribed at a full speed when lactose is the only carbon source. Detail the molecular interactions and events in each mechanism 5.(15) How the control strategy used by trp operon differs from that of lac operon, why?3. (10) Regulation of gene expression in prokaryote usually occurs at the transcription ___level, and the two major mechanisms are___ and ___ . 4. (15) What are the mechanisms that ensure the structure genes of lac operon are only transcribed at a full speed when lactose is the only carbon source. Detail the molecular interactions and events in each mechanism. 5. (15) How the control strategy used by trp operon differs from that of lac operon, why?