Which of the following correctly describes polysaccharides?

Polysaccharides are indeed characterized as long chains of sugar molecules. They are complex carbohydrates composed of numerous monosaccharide units linked together through glycosidic bonds. These long chains can be branched or unbranched and can include a variety of monosaccharide types, each contributing to the overall structure and function of the polysaccharide. Common examples of polysaccharides include starch, glycogen, and cellulose, which play critical roles in energy storage and structural integrity in living organisms.

In contrast to the other options, single sugar units refer to monosaccharides, while linking two monosaccharides describes disaccharides. Short chains of fatty acids do not pertain to polysaccharides at all and instead describe molecules related to lipids. Understanding that polysaccharides are made from numerous sugar units helps clarify their complexity and the diverse roles they play in biology.