only the proteins that the bacteria escherichia coli (e. coli) needs are synthesized at any given time. for…

only the proteins that the bacteria escherichia coli (e. coli) needs are synthesized at any given time. for example, when lactose is available in the environment, e. coli will express the lac genes that allow it to break down lactose to obtain energy. when lactose is not present, these genes are not expressed. which prevents the lac genes in the dna of e. coli from being expressed most of the time? the lac repressor the lac operator the lac promoter

only the proteins that the bacteria escherichia coli (e. coli) needs are synthesized at any given time. for example, when lactose is available in the environment, e. coli will express the lac genes that allow it to break down lactose to obtain energy. when lactose is not present, these genes are not expressed. which prevents the lac genes in the dna of e. coli from being expressed most of the time? the lac repressor the lac operator the lac promoter

Answer

Brief Explanations:

The lac repressor binds to the operator region of the lac - operon in E. coli. When bound, it prevents RNA polymerase from transcribing the lac genes, thus repressing their expression most of the time. When lactose is present, it acts as an inducer, binding to the lac repressor and changing its conformation so that it can no longer bind to the operator, allowing gene expression.

Answer:

the lac repressor