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Consider a bacterial cell with the genotype lacI+ o+ lacZ+ lacY� that was transformed with an F' plasmid carrying lacIs o+ lacZ� lacY+. The expression of the genes lacZ+ and lacY+ in the merodiploid bacterium is ______.

a) Constitutive
b) Induced
c) Repressed
d) Conditioned

User TLGreg
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Final answer:

The expression of the lacZ+ and lacY+ genes in the transformed merodiploid bacterium is constitutive due to the presence of a super-repressor encoded by the lacIs allele on the F' plasmid.

Step-by-step explanation:

The expression of the genes lacZ+ and lacY+ in the merodiploid bacterium with the genotype lacI+ o+ lacZ+ lacY that was transformed with an F' plasmid carrying lacIs o+ lacZ lacY+ is constitutive. This is because the lacIs allele codes for a super-repressor that cannot be inactivated by allolactose, meaning the repressor will continually block the transcription of the lac operon even in the presence of the inducer lactose. Therefore, the lacZ+ and lacY+ genes on the F' plasmid will be expressed constitutively, as their regulation by the super-repressor is not influenced by the presence of lactose.

User Brett Holman
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