And so Ian diagram two, the red strand is that complementary DNA molecule while the blue strand is that mRNA molecule. So in step two we basically have this hybrid complex form where one strand is the DNA and the other strand is the RNA. And so in the next step, in step three, we want to reassociate or we want to dissociate. We want to break apart these two molecules because ultimately we only want the red molecule and not the blue molecule. Now, recall in our discussion of nucleic acids we said that DNA molecules are more stable than RNA molecules. In fact, if we increase the PH, if we make our solution very basic DNA molecules will remain intact but RNA molecules will be destroyed, will be hydrolyzed.