The term "glyco-" indicates the presence of a sugar in an otherwise non-carbohydrate substance: A glycoprotein is a protein to which one or more sugars are connected.
Sugars include fructose?, glucose, maltose?, dextrose?, mannose?.
Two simple sugars, ribose? and deoxyribose?, are principle components of RNA and DNA, respectively.
In culinary terms, sugar is a type of food associated with one of the primary taste sensations, that of sweetness.