Question

QUESTION 11 You are studying a new bacterium that utilizes a sugar called athelose. This sugar can be used as an energy source when necessary. Metabolism of athelose is controlled by the ath operon. The genes of the ath operon code for the enzymes necessary to use athelose as an energy sourc You have found the following: * The genes of the ath operon are expressed only when the concentration of athelose in the bacterium is high. . When glucose is absent, the bacterium needs to metabolize athelose as an energy source as much as possible. The same catabolite activator protein (CAP) involved with the lac operon interacts with the ath operon. Based on this information, how is the ath operon most likely controlled? Choose the correct label for the drawing below. Not all labels will be used
Can someone please answers these for me?

Answer 1

11) As operon is only transcribe when concentration of athelose in bacterium is high, in negative control operon will be negative inducible & in positive control operon will be positive inducible. In positive inducible operon, in absence of high amount of substrate (athelose) regulatory protein is inactive activator & transcription doesn't occur. Thus option a will be combined with option 5. When concentration of athelose is high some of the athelose molecule will bind with the inactive activator & making it active, resulting in the transcription of the operon. Thus, option b will be combined with option 7 & option c will be combined with option 6. In negative inducible operon, in absence of high amount of substrate (athelose) regulatory protein is active repressor & prevents transcription. Thus option d will be combined with option 1. When concentration of athelose is high some of the athelose molecule will bind with the active repressor & making it inactive, resulting in the transcription of the operon. Thus, option e will be combined with option 7 & option f will be combined with option 4.

12) The answer will be it decreases the levels of cAMP in the cell, repressing transcription from the lac operon (Second option).

Explanation: When glucose level is high, cAMP is not made. In absence of cAMP, CAP protein unable to bind with the CAP binding site of the lac operon. In absence of CAP, RNA polymerase unable to bind properly & low level of transcription occurs in presence of lactose. Thus, second option is correct.