Gene regulation

What effect on transcription of the structured and regulatory genes of the lac operon is observed when lactose is present in the environment in large amounts?
(a)   Transcription of the structural genes occur when lactose is present
(b)   The genes are transcribed for only a single generation and then are shut off
(c)   Lactose represses the synthesis of the repressor
(d)   Transcription does not occur
(e)   Beta galactosidase gene activation is turned off


When glucose is present, the levels of cyclic AMP in the cell are low. What occurs in the lac operon of the cell as a consequence of high glucose?
(a)   When glucose is present, the cell will convert it to lactose and use that as the carbon source. 
(b)   When glucose is present, the levels of cyclic AMP are low. Therefore the lac operon genes are transcribed
(c)   When glucose is present, the levels of cAMP are low, CAP alone will not bind to the CAP binding site, and the structural genes are not transcribed. 
(d)   There is no effect