A disaccharide is formed when two monosaccharides join together through a glycosidic bond via a dehydration synthesis (condensation) reaction, where a water molecule is removed. Common pairs of monosaccharides that form disaccharides include:
- Glucose + Glucose → Maltose
- Glucose + Fructose → Sucrose
- Glucose + Galactose → Lactose
So, a pair forming a disaccharide could be any of these combinations, such as glucose and fructose forming sucrose, or two glucose molecules forming maltose.
