| A | B |
|---|
| Invertebrates | Animals without backbones |
| Vertebrates | Animals with backbones |
| Pore | Small hole or opening |
| Stinging cells | Cells that contain a poisonous thread |
| Tentacle | Armlike Part |
| Parasite | A living thing that lives on or in another living thing |
| Flatworm | A worm with a flat body and one body opening |
| Planarian | Can regrow body parts |
| Roundworm | A worm with a round body and two body openings |
| Segmented worm | A worm that has a body divided into segments |
| Mollusk | An invertebrate with a soft body |
| Mantle | A fleshy covering that protects the organs of a mollusk |
| Echinoderm | A spiny skinned invertebrate |
| Tube foot | A hollow structure with a sucker at the end |
| Arthropod | An animal with jointed legs, a segmented body and a hard outer covering |
| Exoskeleton | Hard outer covering of an arthropod |
| Molt | To shed |
| Thorax | Middle part of an insect's body |
| Abdomen | Rear part of an insect's body |
