Partial diploid forms of E. coli were created, each of which contained a complete lactose operon at its normal chromosomal site and the regulatory sequences only (lacI, P, lacO) on a plasmid. Predict the effect of each mutation on the activity of β-galactosidase before and after the addition of inducer. Use - , +, or + + to indicate approximate activity levels. Briefly explain the basis for each of your predictions.

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Mutatiorn (a) No mutations ineither chromosomal (b) A mutation in the plasmid operator, (c) A mutation in the chromosomal Before After or plasmid genes which abolishes its binding to repressor promoter, which reduces affinity of promoter for RNA polymerase by 10-fold_ (d) A lacIgene mutation in the chromosome which abolishes binding of the lacl gene product to inducer (e) A lacI gene mutation in the plasmid, which abolishes binding of the repressor to the inducer abolishes its binding to repressor which abolishes its binding to cyclic AMP ( A chromosomal lacO mutation, which (g) A mutation in the gene for CRP,