What substance makes up the exoskeleton of a bee?

The exoskeleton of a bee is primarily made up of chitin, which is a long-chain polymer that is found in many arthropods, including insects. Chitin provides structural support to the bee, playing a crucial role in protecting its body and maintaining its shape. This substance is lightweight yet strong, which is essential for an insect's mobility and survival.

Additionally, chitin is involved in the overall rigid structure of the exoskeleton, allowing bees to withstand external pressures and prevent water loss. The composition and properties of chitin enable bees to thrive in various environments, ensuring their resilience against physical stressors and predation.

Cellulose, on the other hand, is a component primarily found in the cell walls of plants, not in insect structures. Keratins are fibrous proteins found in hair, nails, and the outer layer of skin in vertebrates, while collagen is a protein that serves as a key structural component in the connective tissues of animals. Thus, these substances do not contribute to the composition of the bee's exoskeleton. Chitin stands out as the correct answer for this question due to its unique role in providing the necessary protective properties for bees and similar organisms.