Final answer:
The lac operon in E. coli is transcribed into a single mRNA molecule that contains the coding sequences for all three enzymes: lacZ, lacY, and lacA. The correct optionis 2.
Step-by-step explanation:
The lac operon in E. coli consists of three structural genes: lacZ, lacY, and lacA. These genes code for proteins involved in lactose metabolism. When the lac operon is transcribed, a single mRNA molecule is produced that contains the coding sequences for all three enzymes.
Therefore, the answer to the question is 1 mRNA molecule.
A single mRNA molecule is transcribed to translate the three enzymes of the lac operon.
To translate the three enzymes of the lac operon, only one mRNA molecule is transcribed. This is because the lac operon is organized such that it allows for the production of a single, continuous mRNA transcript that includes the coding regions for all three enzymes: lacZ, lacY, and lacA. The operon structure, which includes a promoter and operator upstream of these structural genes, ensures coordinated expression. Hence, when the operon is active, a single mRNA that encodes all three enzymes is produced.