Campbell Biology Concepts & Connections Practice Test

RNA polymerase is the enzyme that makes RNA using a DNA template during transcription. It binds to a promoter, temporarily unwinds the DNA, and then adds ribonucleotides to the growing RNA strand in the 5' to 3' direction, pairing bases with the DNA template (A with U in RNA, T with A, G with C, C with G). It doesn’t require a primer, unlike DNA polymerase. This specificity for transcribing DNA into RNA is what sets RNA polymerase apart from the other enzymes listed, which have roles in DNA replication or repair rather than transcription.