And likewise, in the other type of conformation, c three endo, where the third carbon is puckered, this becomes the third carbon. And so now this carbon number one, two for this oxygen will lie along the same plane. And carbon number three is the one that is puckered. So we see that inside our body it's the ring structure, the sugars that predominate. In the case of six member rings, we have the chair confirmation. And in the case of the five member rings we have this envelope form, this puckered form that will basically exist.