06-23-2012, 02:45 PM
The graph shows the relationship between the expression of repressor protein and the expression (transcription and translation) of a lac z gene, in wild-type Escherichia coli. Which of the following mutations in genetic elements of the lac operon could account for this relationship?
A) lac z promoter with no affinity for RNA polymerase
B) lac z protein with increased affinity for substrate
C) lac z protein with no affinity for substrate
D) Repressor with increased affinity for operator
E) Repressor with no affinity for operator
http://imageshack.us/photo/my-images/24/nbme6b3q47.jpg/
I think it's one of the no affinity ones. I'm guessing E? Can someone please explain? I've beaten lac operon to death, but for some reason it just keeps coming back.
A) lac z promoter with no affinity for RNA polymerase
B) lac z protein with increased affinity for substrate
C) lac z protein with no affinity for substrate
D) Repressor with increased affinity for operator
E) Repressor with no affinity for operator
http://imageshack.us/photo/my-images/24/nbme6b3q47.jpg/
I think it's one of the no affinity ones. I'm guessing E? Can someone please explain? I've beaten lac operon to death, but for some reason it just keeps coming back.