| A | B |
|---|
| mollusks | an invertabrate with a soft unsegmented body, such as an oyster, snail, or octopus; many are covered with hard shells. |
| gastropods | a mollusk that glides along on a foot underneath its body, such as a snail or slug. |
| bivalves | a mollusk with 2 shells hinged together, such as a clam or oyster. |
| cephalopods | a mollusk with a distinct head and a foot divided into tentacles, such as a squid or octopus. |
| thorax | the part of an arthropod's body where legs are attached; in some vertabrates, the part of the body between the head and abdomen. |
| abdomen | in arthropods and vertebrates, the part of the body containing many of the animal's organs. |
| exoskeleton | the hard outer support structure of a arthropod |
| arthropods | an invertebrate with jointed appendages and segmented body, such as a spider, insect, or lobster. |
| arachnids | arthropods,such as spiders, ticks, and scorpions that generally that have 2 main body regions. |
| crustaceans | an arthropod such as a lobster or crab, with a hard outer shell and specialized appendages. |
| antennas | one of a pair of aooendages extending from the head of certain arthropods, used for balancing and sensing. |
| metamorphosis | the process off development in which a young organism undergoes changes in appearance to become an adult. |
| nymph | a stage in certain insect metamorphosis, such as that of a grasshopper, in which the organism looks like an adult but has no wings and cannot reproduce. |
| pupa | the stage of metamorphosis in which an insect is often surrounded by a cocoon and many changes occur. |
| echinoderms | an invertebrate with a radial symmetry that live in the ocean, such as a sand dollar or sea star. |
