| A | B |
|---|
| fishes | aquatic vertabrates that are characterized by paired fins, scales and gills |
| cartilage | strong tissue that supports the body and is softer and more flexible than bone |
| atrium | a large muscular chamber that serves as a one-way compartment for blood that is about to enter the ventricle |
| ventricle | a thick walled, actual umping portion of the heart |
| cerebrum | responsible for all voluntary activities of the body |
| cerebellum | coordinates body movements |
| medulla oblongata | controls the functioning of many internal organs |
| gills | adaptation that is NOT characteristic of reptiles |
| cretaceous period | dinosaurs became extinct at the end of this period |
| ectotherm | an animal that relies on interaction with the environment to help it control body tempertature |
| turtles and tortoises | reptiles with shell covered bodies |
| feathers | single most important characteristic that separates birds from other animals is the presence of |
| chest muscles | bird structure that supports flight |
| gizzard | muscular part of birds stomach that contains gravel which crushes food |
| uric acid | birds excrete nitrogenous wastes mostly in the form of |
