Question

How do prokaryotic cells regulate the expression of genes?

• A. Prokaryotic genes code for enzymes instead of proteins, which determine how other genes are expressed.
• B. Transcription factors control which proteins are produced before, during, and after transcription.
• c. Noncoding regions called enhancers determine whether the gene can be translated.
• D. Operons that code for specific proteins are blocked by repressors until they are needed by the cell.The

Answer 1

Prokaryotic gene expression is controlled mainly at the transcriptional level through operons, which can be activated or repressed to regulate gene expression based on the cell's needs. Therefore, the correct option is b.

Step-by-step explanation:

Prokaryotic cells regulate the expression of genes primarily at the transcriptional level. This regulation is achieved through the use of operons, which are a set of genes that are regulated together. Operons may be controlled by mechanisms such as repressible control, activator control, and inducible control. An example is the lac operon, which requires the absence of glucose and presence of lactose for effective transcription. Repressors can bind to an operator region to block the action of RNA polymerase, preventing transcription when the genes are not needed. Conversely, activators can enhance the binding of RNA polymerase to the promoter, thus initiating transcription when the genes are needed.