| A | B |
|---|
| chordates | phylum whose members have a notochord, nerve cord, and slits in the throat area at some point in their lives |
| notochord | a flexible rod that supports a chordates back |
| cartilage | strong, flexible material that is softer than bone |
| vertebrate | an animal that has a backbone |
| vertebrae | the bones that make up the backbone of an animal |
| invertebrate | animals without a backbone |
| endotherm | animal whose body controls and regulates its temperature by controlling the internal heat it produces |
| fish | ectothermic vertebrate that lives in water and has fins |
| swim bladder | internal gas-filled organ that helps a bony fish stabilize its body at different water depths |
| buoyant force | force that water exerts upward on any underwater object |
| cartilaginous fish | type of fish in which its skeleton is made from cartilage |
| bony fish | a type of fish in which the skeleton is made entirely of bone |
| jawless fish | a type of fish that attaches itself to its prey in order to eat |
| amphibian | ectothermic vertebrate that spends its early life in water and adult life on land |
| atria | upper chamber of the heart |
| ventricle | lower chamber of the heart, which pumps blood out to the lungs and body |
| habitat | specific environment in which an animal lives |
| urine | water fluid in which waste is excreted |
| reptile | exothermic vertebrate that has lungs and scaly skin |
| ectotherm | an animal whose body does not produce much internal heat |
