a polymer of sugar molecules is called

A polymer of sugar molecules is called a polysaccharide.

To arrive at this answer, you can break down the question and analyze the key terms:

1. Sugar: Start by understanding what sugar refers to. In the context of biochemistry, sugar typically refers to simple carbohydrates, such as glucose or fructose.

2. Polymer: Identify the term "polymer." A polymer is a large molecule made up of repeating subunits called monomers. In the case of sugar molecules, multiple monosaccharide (sugar unit) molecules can be linked together to form a polymer.

3. Polysaccharide: Combine the terms "polymer" and "sugar." When multiple sugar molecules join together through chemical bonds, they form a complex carbohydrate known as a polysaccharide. Examples of polysaccharides include starch, cellulose, and glycogen.

Therefore, based on this analysis, a polymer of sugar molecules is called a polysaccharide.