What is the role of dna segments that do not code for

The non-coding regions of DNA are called introns. They are significant in evolution since they offer a great 'recipe' for recombination with genes/exons. Therefore, this offers variations among individuals on which natural selection could act upon to help a population adapt to changes in the environment. Introns also offer an additional step in gene regulation through the splicing of introns in making of mRNA.

i do not know and i have a 100 in this class

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.