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. So once again, DNA polymerase catalyzes the formation of the phosphor diester bond. And the three prime, a hydroxyl group of the sugar on the primer nucleophilicly attacks the innermost phosphorus atom of this triphosphate group of the dNTP molecule that we are base pairing with this base found on the DNA template. And so this forms our phosphodiator bond.