In the lac operon of E. coli, the repressor gene (lacI =I) may exist as wild type (I), a null (I-), a superrepressor mutant (Is), or
a trans-dominant negative (I-d), the promoter (Plac) may exist as wild type (P+) or non-active (P-), the operator (laco) may
exist as wild type (O+) or cis-dominant (Oc), beta galactosidase (lacZ) may exist as wild type (Z+) or inactive (Z-), and
permease (lacY) may exist as wild type (Y+) or inactive (Y-). Complete the table below, using + and 0 to indicate whether
the bacteria will be able to grow on lactose medium.
growth yes or no
Question 7
IsP+O+Z+Y+
IsP+OcZ+Y+
I-dP+O+Z+Y+
I-P+O+Z+Y-
I+P+O+Z-Y+
I-dP+O+Z+Y-
I+P+O+Z-Y+
I+P-O+Z+Y-
I+P+O+Z-Y+
I-dP+O+Z+Y-
I+P+OcZ-Y+
