The lactose (lac) operon in E. coli is an example of a gene that is repressed when lactose is not available in a cell. In 3-5 sentences, explain what this means, using correct terminology. (4 points)

Answer 1

The lactose operon in E. coli refers to a cluster of genes involved in lactose metabolism. When lactose is not present in a cell, a repressor protein called LacI binds to a specific region on the DNA called the operator site. This blocks the promoter site, preventing RNA polymerase from initiating transcription of the genes involved in lactose metabolism. Therefore, the lac operon is repressed (switched off) in the absence of lactose, ensuring that the cell conserves energy by not producing unnecessary lactose-metabolizing proteins.

Answer 2

but what does this mean