| A | B |
|---|
| vertebrate | An animal with a segmented backbone |
| chordate | An animal with a nerve cord running down their back |
| endoskeleton | An inner supporting structure of bone |
| cartilage | a soft bone-like material that is part of the endoskeleton of an animal |
| tetrapod | an animal with four legs or limbs such as a turtle, salamander, or horse |
| invertebrate | an animal without a backbone |
| exoskeleton | a hard covering that protects an invertebrates body |
| biped | an animal with two feet |
| amphibians | Breathe through gills when they are young and through lungs when they are full grown |
| arthropods | The largest group of invertebrates; include insects, spiders, crabs, shrimp, and lobster |
| segmented worms | Worms that have bodies divided into compartments |
| cnidarians | Jellyfish, corals, hydras, and sea anemones are all _____________________. They have stinging cells |
| sponges | ____________ belong to a phylum called Porifera; come in different colors and attach themselves to ocean floor |
| echinoderms | Have spiny skin and move slowly; sea stars and sea urchins |
| mollusks | Clams, snails, oysters, squid and scallops are all ______________. |
| shed | An exoskeleton must be ________________ as an arthropod grows |
| arachnids | These were probably the first animals to live on land |
| largest | Vertebrates include the _______________animals on land and in the sea |
| mammals | _______________ a class of vertebrates with fur or hair, breathe through lungs, and feed their young with mother's milk |
| soft boned | The seven classes of vertebrates include jawless fish, bony fish, ____________ fish, |
| reptiles | The seven classes of vertebrate include three classes of fish and birds, mammals, amphibians, and ____________ |
