What the main structural difference between a monosaccharide, a disaccharide, and a polysaccharide?

Hi!

These are all , which vary in structural complexity. Specifically, they differ in how many monomers comprise the overall structure of the molecule.

Monosaccharides are the monomers, or "subunits," which make up carbohydrates. In this way, they are the most simple in structure. Glucose is an example of a single monosaccharide. In aqueous solution, their structure usually consists of a single ring.

Disaccharides consist of two monomers. So, two monosaccharides linked together. For instance, two single glucose molecules can link together to form maltose, a two-ring structure.

Similarly, a polysaccharide consists of many (more than two) monomers. So, its structure will exhibit many rings. Polysaccharides are the most complex of the three.

It will be easy to distinguish these if you can remember the common prefixes mono-, di-, and poly-, meaning "one," two," and "many".