1. Cnidarian Reproduction Asexually – budding (polyp form) Sexually –have separate male and female medusae that produce gametes that join through external fertilization to produce polyps.

3. Flatworms - Platyhelminthes Bilateral Symmetry Free-living in freshwater or parasitic in a host Has all three layers (endoderm, mesoderm, ectoderm) Acoelomate – no body cavity.

4. An Important Group Many nasty parasitic infections. Dugesia Tapeworms Flukes

6. Flatworm Feeding Free living flatworms are scavengers. Parasitic flatworms use specialized structures (usually with hooks) to attach to a host.

7. Respiration & Excretion Excretion - Flame cells remove excess water Respiration - Oxygen diffuses into body cells directly.

8. Flatworm Nervous Systems First appearance of cephalization. Primitive brain. Eyespots

9. Flatworm Reproduction Sexually - Hermaphrodites – internal fertilzation. Asexually – fission – when damaged, regenerates new body parts. Proglottids – found in tapeworms – each is shed off individually.