What is an exoskeleton?

An exoskeleton, a key feature of invertebrate arthropods and mollusks, is a rigid structure composed of chitin and calcium carbonate. Exoskeletons contain rigid and resistant components that fulfill a set of functional roles in many animals including protection, sensing, support, and dessication-prevention. But due to the rigid inorganic properties of the non-living exoskeleton, there are growth restraints that come as collateral issues. Although certain creatures, such as mollusks, are able to grow their shells by adding material to the edges, most exoskeletons are shed by molting and then regrown. Molting is an advantageous biological process for organisms with an exoskeleton as it helps in metamorphosis and damage repair, but the organisms expose their soft interior in the process and become vulnerable for the predators.

Examples of exoskeleton organisms