15. Exoskeleton

This is a picture of a crab. A crab is an example of an animal with an exoskeleton. An exoskeleton is the hard covering located on the outside of an animal that protects and supports the animal's body. Most invertebrates have exoskeletons, which includes arthropods and crustaceans such as a crab. A crab has a shell that is the shape of the crab's entire body. This shell is the crab's exoskeleton, and it is because of the crab's exoskeleton that the outside of a crab is hard.