- a hard encasement deposited on the surfave of an animal
- as the animal grows, the exoskeleton changes size by the enlargement of the
diameter of the shell when new layers are added to the outer edge
- Cuticle (a polysaccharide similar to cellulose) makes up almost half of the cuticle.
Fibrils of the chitin are embedded in a matrix made of protein and form composit
material which increases the flexibility and strength of the exoskeleton.
- hardened via the addition of organic compounds and non-organic salts
- as the organism grows the exoskeleton must be molted and relaced by a larger
- Typically seen in arthropods and mullusks