A partial diploid E. coli cell of lacI+lacP+lacOc lacZ-lacY-/ lacI- lacP+ lacO+lacZ-lacY+ genotype will synthesize:
A. lacZ but not lacY gene product in the presence of lactose.
B. lacY but not lacZ gene product in the presence of lactose.
C. lacY but not lacZ gene product in the absence of lactose.
D. neither lacZ nor lacY gene products in the presence of lactose.
E. both lacZ and lacY gene products in the absence of lactose.
Ans: B. lacY but not lacZ gene product in the presence of lactose.
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