Key Concepts Differences between Prokaryotes and Eukaryotes Three kinds of rna polymerases(, Il, and IID) in eukaryotic cells Promoters and enhancers Upstream regulatory elements Transcription factorsKey Concepts • Differences between Prokaryotes and Eukaryotes • Three kinds of RNA polymerases (I, II, and III) in eukaryotic cells • Promoters and Enhancers • Upstream regulatory elements • Transcription factors