So again, in the first step, we utilize a phenylalamine, a diatomic water molecule. We use NADPH to basically give us this. And by using the reducing power of this molecule, we transform the phenylalanine into tyrosine. So one of the oxygen atoms goes on to this ring of the phenomealine, and the other one is used to form a water molecule. Now, once we form tyrosine, what happens next? Well, next we basically have to use an amino transferase to transfer the alpha amino group from tyrosine onto an alpha keto acid.