And then two more steps take place and ultimately we're able to break down the galactose into ATP molecules. But if both of these alleles, both of these genes are impaired in some way, that means we cannot actually create that functional galactose one phosphate urilotransphrase. And so what happens is our cells will be able to break down the lactose into these two molecules, then the galactose will be broken down or will be essentially modified to form the galactose one phosphate. But the galactose one phosphate will not be able to form these molecules here. And so what that means is, as we ingest the lactose, if we have classic galactosemia, there will be a build up of this galactose as well as the galactose one phosphate. And that can be very toxic to our body.