Support, Control, and Movement
A fluid-filled internal cavity surrounded by muscle tissue.
A Hydrostatic skeleton
The movement of substances from an area of higher concentration to an area of lower concentration.
Is Diffusion
The fluid-filled internal cavity
A coelom
Tiny holes on the surface of an organism through which oxygen enters the body and carbon dioxide leaves the body.
Is Spiracles
A netlike control system that sends signals to and from all parts of the body.
A Nerve Net
Some animals move in a wavelike motion called.
Is Undulaton