The Organization of the Lac Operon, from Upstream to Downstream

Question

The organization of the lac operon, from upstream to downstream sequences, is represented by:
A) repressor gene -> lacZ -> lacY -> lac A
B) lacZ -> lacY -> lac A
C) lacZ -> lacY -> lac A -> operator -> promoter
D) operator -> promoter -> lacZ -> lacY -> lac A
E) promoter -> operator -> lacZ -> lacY -> lac A

Accepted Answer

The correct organization of the lac operon includes the promoter region, followed by the operator, and then the structural genes lacZ, lacY, and lacA in that order. The promoter is where RNA polymerase binds to initiate transcription, and the operator is the site where the repressor binds to regulate the operon's activity.