What is formed when two monosaccharides join together?

When two monosaccharides join together, they form a disaccharide. This process occurs through a dehydration synthesis reaction, where a water molecule is removed as the two monosaccharides bond together. The resulting molecule consists of two sugar units linked by a glycosidic bond.

Disaccharides, such as sucrose (made from glucose and fructose) and lactose (composed of glucose and galactose), are important in various biological processes and serve as energy sources. In contrast, a polysaccharide consists of multiple monosaccharides linked together, and an oligosaccharide involves a short chain of three to ten monosaccharides. Therefore, while all these terms relate to carbohydrate structures, only the disaccharide accurately describes the product of two monosaccharides coming together.