Galactose
A sugar contained in milk.
Galactose makes up half of the sugar called lactose that is found in milk.
Lactose is called a disaccharide, di meaning 2, since lactose is made up of two sugars, galactose and glucose, bound together.
Galactose is metabolized (used) through the action of an enzyme called GALT (galactose-1-phosphate uridyl transferase).