Part a which of the following features is a significant difference in the function of dna polymerases versus rna polymerases? see section 17.1 (page) . view available hint(s) which of the following features is a significant difference in the function of dna polymerases versus rna polymerases? see section 17.1 (page) . rna polymerase does not require a primer to add new nucleotides. dna polymerase extends the growing chain in the 5' to 3' direction, whereas rna polymerase extends growing chains from 3' to 5'. rna polymerase, but not dna polymerase, is an enzyme. only rna polymerase adds nucleotide precursors (dntps) to a growing chain.