What molecular structure is a characteristic of starch?

Starch is primarily composed of long chains of glucose molecules, which serve as its monomer units. These glucose units are linked together through glycosidic bonds, forming either amylose (a straight chain form) or amylopectin (a branched form). The presence of these long chains allows starch to function as an important energy storage molecule in plants, as it can be readily broken down into glucose units when energy is required.

In contrast to starch, fatty acids and amino acids focus on different biomolecules: fatty acids are components of lipids, while amino acids form proteins. Additionally, while starch itself can be considered a polysaccharide, the emphasis on it being made up specifically of glucose molecules is what distinctly defines its structure. Thus, the understanding that starch comprises long chains of glucose is fundamental in identifying its molecular characteristics and its role in nutrition and energy storage.