| A | B |
|---|
| Exoskeleton | hard, outer covering |
| Tube Feet | hollow, thin-walled tubes that end as a suction cup |
| Radula | tongue-like organ with rows of teeth |
| Setae | bristle-like structures on each body segment of a worm |
| Mantle | covers the body organs in the mollusks |
| Spiracle | openings on the abdomen and thorax where air enters and wastes leave the insect |
| Appendages | legs, antennae, claws and pinchers |
| Molting | when an exoskeleton is shed and replaced by a new one |
| Open Circulatory System | heart moves blood out into open spaces |
| Closed Circulatory System | heart moves blood through a seris of vessels |
| Gizzard | muscular organ that grinds organic material and soil |
| Crop | a sac used for storage in the earthworm |
| Metamorphosis | changes in body form as an organism develops |
| Gill | organ in mollusks that exchanges carbon dixiode for oxygen in water |
| Water Vascular System | water-filled canals with tube feet |
