1: Yes. The sugar in milk comes from naturally occurring lactose, not added sugar
2:Lactose-free milk contains an enzyme called lactase that helps break down the naturally-occurring lactose into two simple sugars, glucose and galactose. There is no added sugar in plain lactose-free or regular milk
3:When the enzyme has attached to the substrate, the molecule is called the enzyme-substrate complex. For example, the sugar found in milk is called lactose.
