Question

You are studying a 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 source.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?Drag the labels onto the diagram to identify the small molecules and the states of the regulatory proteins. Not all labels will be used.POSITIVE CONTROLa) Inactive Activator (not glowing, w/o yellow square)b) cAMPc) Active Activator (glowing, w/ yellow square)NEGATIVE CONTROLd) Active Repressor (glowing, w/o yellow square)e) athelosef) Inactive repressor (not glowing, w/ yellow square)

Answer 1

POSITIVE CONTROL

c) Active Activator

d) Active Repressor

NEGATIVE CONTROL

f) Inactive repressor

a) Inactive Activator

b) cAMP

Explanation:

The positive controls are those groups in the experiment whose treatments are expected to confirm previously known results, thereby enabling the comparison of these results with the target group. In this case, both active activators and repressors are able to give results that can be compared with the test group

The negative controls are those experimental groups where no response is expected. In this case, both inactive activators and repressors, and cAMP (which is a secondary messenger in diverse biological processes but is not involved in this pathway), are not expected to produce any measurable response.