The digestion of carbohydrates starts as soon as food reaches to mouth where the salivary amylase converts starch into maltose but in small amount then they directly enter the small intestine passing through stomach and here pancreatic amylase converts the left starch to maltose which further broken down by maltase to two molecules of glucose, lactose into glucose and galactose by lactase and sucrose by the action of sucrase converts into glucose and fructose.