Introduction to Invertebrates

1. Introduction to Invertebrates Laboratory 22

2. Introduction to Invertebrates • An invertebrate is an animal without a backbone. • The group includes 95% of all animal species

3. Introduction to Invertebrates • Acoelomates • lack a body cavity (coelom) • bilateral symmetry • one internal space, the digestive cavity.

4. Introduction to Invertebrates • The good the bad and the ugly!!! ( 4)

5. Introduction to Invertebrates • Phylum Porifera • Sponges • Sessile aquatic animals • Some are freshwater species, most are marine-ranging from tidal zones to depths exceeding 5.5 miles. • shapes of their bodies are adapted to maximize the efficiency of the water flow

6. Introduction to Invertebrates • Sponges • Phylum Porifera • Sponges do not have nervous, digestive or circulatory systems. • Instead, rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes

7. Introduction to Invertebrates • Cnidarians • Phylum Cnidaria (pronounced /naɪdɛəriə/ with a silent c) • phylum containing over 9,000 species of animals found exclusively in aquatic and mostly marine environments. • Jellyfish • Hydra

8. Introduction to Invertebrates • Cnidarians • Phylum Cnidaria • Two basic body forms are seen : swimming medusae and sessile polyps

9. Introduction to Invertebrates • Cnidarians • Phylum Cnidaria • Their distinguishing feature is a cnidocyte, specialized cells that they use mainly for capturing prey.

10. Introduction to Invertebrates • Cnidarians • Phylum Cnidaria • Have no brains or central nervous systems. • Instead they have nerve nets that generate signals in response to various types of stimulus, such as odors

11. Introduction to Invertebrates • Phylum Platyhelminthes • Flatworms • Planarian • Fluke • Tapeworm • Over half of all known flatworm species are parasitic, and some do enormous harm to humans and their livestock

12. Introduction to Invertebrates • Flatworms • Phylum Platyhelminthes • no body cavity • no specialized circulatory or respiratory organs

13. Introduction to Invertebrates • Flatworms • Phylum Platyhelminthes • restricted to flattened shapes that allow oxygen and nutrients to pass through their bodies by diffusion.

14. Introduction to Invertebrates • Flatworms • Phylum Plaatyhelminthes • Taeniasolium

15. Introduction to Invertebrates • Flatworms • Phylum Plaatyhelminthes

16. Introduction to Invertebrates • Phylum Nematoda • Roundworms • over 28,000 have been described, of which over 16,000 are parasitic • have a digestive system that is like a tube with openings at both end

17. Introduction to Invertebrates • Roundworms • Phylum Nematoda Ascaris giant intestinal/lung roundworms Human feces 200,000 X day

18. Introduction to Invertebrates • Bloody sputum • Cough • Low-grade fever • Vomiting worms • Passing of worm in stool • Gallstone formation • Control of is based on drug treatment, improved sanitation and health education. • Anthelmintic Drugs

19. Introduction to Invertebrates • Roundworms • Phylum Nematoda • Filarial worm • Obstruction of the lymphatic vessels • broad spectrum antibiotic combined with ivermectin

20. Introduction to Invertebrates • Roundworms • Phylum Nematoda • Trichinella

21. Introduction to Invertebrates • Roundworms • Phylum Nematoda • Trichinella • Trichinosis - fever, muscle soreness, pain and swelling around the eyes. • Chest pain may be experienced since the parasite may become imbedded in the diaphragm • Death • COOK FOOD PROPERLY

22. Introduction to Invertebrates • Roundworms • Phylum Nematoda • The threat of roundworm parasites infecting humans in developed countries is rising?????

23. Introduction to Invertebrates • Roundworms • Phylum Nematoda • Nematodes have successfully adapted to nearly every ecosystem Heterohabditis Nematodes