Illustrated Glossary of Organic Chemistry

Monosaccharide (simple sugar; simple carbohydrate): A carbohydrate that cannot be hydrolyzed into two or more simpler carbohydrates.

H3O+

No change

D-Glucopyranose is not broken down into two or more carbohydrates upon hydrolysis, so D-glucopyranose is a monosaccharide.

H3O+

+

Lactose hydrolysis yields one molecule each of D-galactopyranose and D-glucopyranose, so lactose is a disaccharide.

H3O+

Amylose hydrolysis yields many molecules of D-glucopyranose, so amylose is a polysaccharide.