So as this bond is being formed, the Pi bond is being broken and a Sigma bond is being formed between this oxygen and this H atom. And we form a tetrahedral intermediate molecule. Now, this tetrahedral intermediate molecule is not very stable. And so what will happen is a rearrangement will take place. And in this rearrangement, the molecule that is basically kicked off is the first product of this reaction. In this particular case, because we used Zelulose phyphosphate, the product molecule is glyceroldehyde three phosphate.