Now, what that means is these will essentially fold onto themselves to basically interact because these two sequences of RNA are complementary. And that means when they interact, they form these hydrogen bonds which is a stabilizing effect. And we form the following stem of this structure. Now, this is the loop and that's because when these two interact we have this section here that is not complementary to itself. And so it will form this loop structure in which we don't have any hydrogen bonds formed between these bases. And that means this will destabilize this localized region of the structure.