Well, this carbon atom number four in galactose, it points up, in glucose, it points down. So it might seem that the only thing we have to do is basically flip this down. But that's not actually what happens because our cells follow a slightly more complicated pathway. So we have an enzyme known as galactokinase. And what a galactokinase does, well, it's a kinase, so it has to use an ATP and it basically transfers a phosphoryl group from that ATP onto carbon number one of galactose, and we form galactose one phosphate. So one phosphoryl from the ATP onto this oxygen here to form this galactose one phosphate.