And when we go down ten of these base pairs, our degree measure is 36 times ten or 360 degrees. Now, the final observation they are able to deduce following these X ray diffraction patterns is the fact that the entire diameter of this DNA molecule is 20 angstroms. Now, what about the base pair? So how exactly do these base pairs actually stack within the interior portion of our DNA molecule? Well, they are able to basically show that one purine always bonds to a single Pyridine and the other purine always binds to the other Pyridine. In DNA molecules, they are able to show that our guanine bonds with cytosine and adenine binds with thiamine.