So we have these electrons attacking this phosphate and that kicks off this bond. And so this is this molecule that is formed here, the Pyrophosphate. It is broken. And then we form that bond between this molecule and between this oxygen and this P atom. And so we form that phosphodia Esther bond. Now notice as we form the polynucleotide chain, we form that chain from the five N to the three N. And in fact, the DNA molecule, the DNA polymerase always forms that polynucleotide chain in this direction, beginning at the three end and traveling towards that or beginning the five end and traveling towards the three end.