And that phosphate group is in turn attached to this oxygen here that is linked to carbon number five of this adjacent sugar. And that's exactly what a three to five linkage actually means. So we have this oxygen on the third carbon, is linked to this oxygen on the fifth carbon of that adjacent sugar. Now, what do we mean by phosphol diaster? So phosphol means we have this phosphate group in between these two aster bonds. So these two bonds are the asterbonds.