The E. coli lac operon encodes three genes. These genes ____
a. cleave lactose into glucose and galactose, produce transacetylase, and actively transport lactose into the cell
b. encode an enzyme that cleaves glucose, a transport protein for active transport, and a transacetylase enzyme
for solubilizing lactose in the cytosol
c. encode an enzyme that cleaves lactose, a transport protein for active transport of lactose, and a transacetylase
enzyme whose function is unknown
d. catalyze the synthesis of lactose from glucose and galactose, produce transacetylase, and actively export
lactose from the cell
e. directly interact with the Lac repressor and initiate their own transcription
ANSWER: c
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