11. The new molecule, consisting of two monosaccharides, is called a disaccharide . 12. The disaccharide is hydrolyzed into two molecules of glucose by the enzyme trehalase. 13. It may also be involved in the addition of a repeated disaccharide unit. 14. Disaccharides can be classified into two types : reducing and non-reducing disaccharides.15. Disaccharides can be classified into two types : reducing and non-reducing disaccharides . 16. Monosaccharides contain one sugar unit, disaccharides two, and polysaccharides three or more. 17. Larger sugars such as disaccharides and polysaccharides can be named to reflect their qualities. 18. Galactose itself comes from the metabolism of the disaccharide lactose into glucose and galactose. 19. Another important disaccharide is lactose, consisting of a glucose molecule and a galactose molecule. 20. Sucrose is a disaccharide , a molecule derived from two simple sugars ( monosaccharides ).