Endoskeleton
This is called bark.
The external covering on arthropods is called the exoskeleton (or cuticle). It is made of a tough protein called chitin, a long chain polymer comparable to cellulose. Because it's inflexible, arthropods need to shed it (moult) in order to grow.
Schlera
The tough outer covering of the bone is called the "periosteum."
The tough outer covering of bone is called the periosteum. It is a dense connective tissue that protects the bone and plays a role in bone growth and repair.
The hard outer covering of an insect is called the exoskeleton. It provides protection and support for the insect's body, as well as serving as a attachment point for muscles. The exoskeleton is made of a tough substance called chitin.
It is a shell, as in a cockle shell or oyster shell.
Yes. Arthropods are characterized by an exoskeleton made mostly from the tough protein chitin, also joint appendages and segmented bodies.
The outer covering of euglenas is called a pellicle. It is a flexible layer made up of protein strips called pelliculin. The pellicle helps euglenas maintain their shape and structure while allowing them to move and change shape.
Yes, the cuticle is the body covering of a cricket. It is a thin, tough outer layer that protects the cricket's body and helps prevent dehydration.
Cell Wall