1. WARM UP
Describe two or three ways jellyfish are more like “traditional” animals than sponges.

2. Phylum Platyhelminthes
Flatworms Notes
Phylum Platyhelminthes

3. General Characteristics
Flattened bodies
Single gut opening
Digestive organ
Nervous organs
Cephalization

4. Planarians Free-living Reproduction Moist habitats Move with cilia
Eyespots and nervous control
Reproduction
Asexually divide
Sexually with internal fertilization

5. Flukes Parasites Multiple stages and hosts in life cycle Blood fluke
Liver fluke
Swimmer’s itch

6. Tapeworms Intestinal parasites
Use scolex to attach
Grow by adding body segments (proglottids)
Each has sperm and eggs
Fertilized segments break off

7. WRAP UP
List three or four advancements in the structure and function of flatworms (especially planarians) that make them more advanced than the Porifera and Cnidaria.