Animals that do not have a backbone. Invertebrates Animals that do not have a backbone.

Sponges(Poriferans) Many pores and canals Do not move around, live most of their lives attached to things-sessile No tissues or organs-simplest animals No symmetry

Coelenterates Tentacles Stinging cells One opening No organs, only tissues Radial symmetry

Mollusks Soft bodies Some have shells Bilateral symmetry Some with tentacles or arms with suction cups scallop

Arthropods have a segmented body, jointed legs, exoskeletons(hard outside covering) Bilateral symmetry

Echinoderms spiny skin, rays or arms tube feet Radial symmetry Water Vascular System

Worms Long tube-like bodies May be flat Usually no definite head No legs or antenna