What are the functions of mono- and disaccharides in the human body?

Monosaccharides:
Ribose and deoxyribose are included in RNA and DNA, respectively (nucleic acids).
Glucose is the main source of energy that is involved in the metabolic processes of the body.
Fructose is a substitute for sugar in food, it is much sweeter, so its harm to health is less.
Disaccharides:
Sucrose is a food product, common sugar, contains fructose and glucose.
Maltose is a source of energy for seed germination.
Lactose – milk sugar, is part of milk during feeding.