Which glycan provides structural support in the exoskeleton of arthropods?

The question asks which glycan provides structural support in the exoskeleton of arthropods. Step 1: Recall the composition of arthropod exoskeletons. The exoskeleton of arthropods (insects, crustaceans, arachnids) is a tough, protective outer layer. Its primary structural component is a polysaccharide. Step 2: Evaluate the given options. A. Mannose*: This is a monosaccharide (simple sugar), not a complex structural polymer. B. Chitin*: This is a long-chain polymer of N-acetylglucosamine, a derivative of glucose. It is known to be the main component of the cell walls of fungi and the exoskeletons of arthropods. C. Glycogen*: This is a polysaccharide used for energy storage in animals, primarily in the liver and muscles. D. Starch*: This is a polysaccharide used for energy storage in plants. Step 3: Identify the correct glycan. Based on the biological roles of these glycans, chitin is the specific polysaccharide that provides structural support in the exoskeleton of arthropods. The final answer is B That's 2 down. 3 left today — send the next one.