RNA polymerase in a prokaryote is composed of several subunits. Most of these subunits are the same for the transcription of any gene, but one, known as sigma, varies considerably. Which of the following is the most probable advantage for the organism in having such variability in RNA polymerase?

Question

Quizplus · Accepted Answer

Having variability in the sigma subunit of RNA polymerase allows the polymerase to recognize different promoters under certain environmental conditions. This means that the transcription of certain genes can be turned on or off in response to specific signals or conditions in the environment. This is an important mechanism for regulating gene expression in prokaryotes. The other answer choices are not directly related to the function of the sigma subunit in RNA polymerase.

RNA Polymerase in a Prokaryote Is Composed of Several Subunits