| A | B |
|---|
| Appendage | An extension of an animal's body. |
| Arachnids | Arthropods with eight legs, two body segments, and simple eyes. |
| Arthropods | Animals with jointed appendages, body segments, exoskeletons, and complex circulatory and nervous systems. |
| Bivalves | Mollusks that have two shells held together by powerful muscles. |
| Cephalopods | Mollusks that have tentacles. |
| Crustacean | Water-breathing animals with jointed body and limbs, covered with firm crustlike shells. |
| Echinoderms | Animals with hardened, bumpy or spiny plates under their skin. |
| Endoskeleton | An internal skeleton. |
| Exoskeleton | A rigid outer covering. |
| Gastropods/Univalves | Mollusks that have one or no shell. |
| Insects | Arthropods that have tree pairs of jointed legs. |
| Metamorphosis | A change in appearance due to development. |
| Mollusks | Soft-bodied animals that may have shells to protect them. |
| Molting | The process of shedding and replacing an exoskeleton. |
| Myriapods | Animals with a body of numerous segments, with jointed legs on nearly every segment. |
| Radula | Rough tongue-like object found on gastropods. |
| Tentacles | Armlike extensions that some animals use in catching food and bringing it into the body cavity. |
| Tube Foot | Cuplike structure for suction that helps echinoderms walk. |
