And so we have this type of one to two interaction as opposed to one to one in this case. Now, the final type of secondary structure that I'd like to discuss are the beta turns. So what do we mean by beta turn? And why do our polypeptides need to create these beta turns in the first place? Well, if we examine the three dimensional structure of polypeptides will see that the structure is very, very compact. And the compactness of that polypeptide is because the polypeptide is able to make many sharp turns as it conforms into that three dimensional structure.