2. Invertebrates Kingdom Animalia

3. 97% Invertebrates (lack a backbone) Examples Examples - worm, jellyfish, lobster, spiders, etc. Click on diagram to watch video…

4. Patterns of Symmetry Symmetry Symmetry - Arrangement of body parts around a point or central axis. Four types Four types: Asymmetrical Asymmetrical - no definite symmetry Spherical Spherical - shaped like globes Bilateral Bilateral Radial Radial

5. Radial Symmetry any Divided into halves by any plane that passes through its longitudinal axis. Example - hydra, starfish

6. Bilateral Symmetry one Divided into halves by placing one specific plane through the longitudinal axis of an organism. Example - butterfly

7. Terminology Cephalization - An adaptation that allows organisms’ sensory organs to enter an environment first. Specialization - An adaptation of a cell for a particular function. Anterior - front end Posterior - hind end Dorsal - top Ventral - bottom

8. Patterns of Development Zygote - Embryo - Blastula - Gastrula Blastopore, or depression, is produced in the blastula stage. Gastrula stage - Formation of ectoderm, endoderm, & mesoderm

9. Invertebrate Phyla - Phylum Porifera Filter feeders Non-motile(sessile) Asexual/sexual reproduction Example - Sponges

10. Phylum Cnidaria Shapes - polyp, medusa, mixed colonies. Body parts - tentacles, nematocysts (stingers), gastrovascular cavity Asexual/sexual reproduction; hermaphroditic Example - Jellyfish

11. More phyla... Phylum Phylum Platyhelminthes Platyhelminthes - free-living & parasitic, marine, asexual/sexual reproduction - Examples-flatworms (flukes, planaria, tapeworms) Phylum Phylum Nematoda Nematoda - free-living & parasitic; roundworms - Example-Ascaris, trichinella Phylum Phylum Rotifera Rotifera - free-swimming; feed on algae, bacteria, & protozoa - Example-Rotifers

12. Phylum Annelida coelem True body cavity, or coelem. Body is segmented. Well-developed organ systems setae Most annelids have external bristles called setae.

13. Earthworm Dissection