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E. coli cells with a mutated z gene of t...

E. coli cells with a mutated z gene of the lac operon cannot grow in medium containing only lactose as the source of energy because

A

They cannot synthesize functional beta galactosidase

B

They cannot transport lactose from the medium into the cell

C

The lac operon is constitutively active in these cells

D

In the presence of glucose, E. coli cells do not utilize lactose

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The correct Answer is:
A
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