| A | B |
|---|
| vertebrate | animal with a backbone |
| cold-blooded | temperature dependent on the environment |
| warm-blooded | temperature not dependent on the environment |
| gills | feathery structures through with water dwelling animals breathe |
| fish | water dwelling animals with scales, fins and gills |
| jawless fish | lamprey and hagfish |
| cartilage fish | endoskeleton of cartilage |
| sharks and rays | types of cartilage fish |
| bony fish | endoskeleton made of bone, gills with covers |
| swim bladders | gas filled sac that allows bony fish to float |
| amphibians | lead a double life in water and on land |
