| A | B |
|---|
| The ability of some animals, such as flatworms, to regrow lost parts of their bodies. | Regeneration |
| The protective cellular covering of the bodies of endoparasitic flukes that prevents them from being digested by their hosts. | Tegument |
| Rectangular body sections of tapeworms. | Proglottids |
| Roundworms belong to this phylum. | Nematoda |
| The opening at the other endof the digestive tract of roundworms that is used to eliminate wastes. | Anus |
| The simplest animals with bilateral symmetry. | Flatworms |
| Concentration of sense organs at the anterior end. | Cephalization |
| The structure that is used by planarians to take in food. | Pharynx |
| Schistosome worms belong to this phylum. | Platyhelminthes |
| Flatworms use this method to take up oxygen and release carbon dioxide from their bodies. | Diffusion |
| Organisms that feed by using cilia to sweep food into their mounths. | Rotifers |
| A noncellular layer that protects a roundworm. | Cuticle |
| Being infected with this worm can cause a condition known as elephantiasis. | Filarial |
