Part a in addition to splicing, additional modifications at the 5' and 3' end are required to generate a mature mrna. what is the significance of these modifications? see section 17.2 (page) . view available hint(s) in addition to splicing, additional modifications at the 5' and 3' end are required to generate a mature mrna. what is the significance of these modifications? see section 17.2 (page) . these modifications allow the mrna to be recognized by the protein synthesis machinery and protect it from degradation. these modifications are required so that the mrna is retained in the nucleus. these modifications ensure that the mrna is properly spliced. these modifications ensure that rna polymerase recognizes the proper promoter sequence.