1. 1 Phylum Platyhelminthes Oklahoma City Community College Created by Dennis Anderson Zoology Moore High School modified by Tamara Lookabaugh

2. 2 Phylum Platyhelminthes General Characteristics 1.Flat worms 2.Triploblastic 3.Acoelomate 4.Bilateral symmetry 5.Reproduction Hermaphroditic Monoecious, internal fertilization, indirect development with complex steps 6.Digestion is incomplete, Cestoda – no system 7.Nervous System – 1-5 Paired lateral nerve cords & cerebral ganglion Planarian

3. Platyhelminthes Characteristics 8.20,000 species, about 85% parasitic 9.Excretion - Flame cells 10. Sense organs – Ocelli = eyespots, Auricles = chemical receptors Statocysts = gravity, water direction 11. No circulatory, respiratory or skeletal 3

4. 4 MyxozoaMyxozoa ArthropodaArthropoda AnnelidaAnnelida MolluscaMollusca LophophoratesLophophorates HemichordataHemichordata ChordataChordata OtherpseudocoelomatesOtherpseudocoelomates NematodaNematoda PoriferaPorifera CtenophoraCtenophora CnidariaCnidaria PlacozoaPlacozoa PlatyhelminthesPlatyhelminthes NemerteaNemertea CiliophoraCiliophora SarcomastigophoraSarcomastigophora MicrosporaMicrospora ApicomplexaApicomplexa MesozoaMesozoa EchinodermataEchinodermata CrustaceaCrustacea ChelicerataChelicerata UniramiaUniramia ProtochordatesProtochordates

5. 5 Acoelomate EctodermMesodermEndoderm No body cavity!

6. 6 Phylum Platyhelminthes: Class Turbellaria Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Acoelomate Planarian cross section

7. 7 Nervous System Lateral nerve cord Connectives Auricle Eye spot Cerebral ganglion

8. 8 Excretory System Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

9. 9 Excretory system continued

10. 10 Digestive system

11. 4 Classes of Platyhelminthes 11 Class Turbellaria – “Commotion-like” Free living Class Trematoda(Flukes) – “Perforated form” Endo parasitic Class Monogenea – “ Single Origin” Most are ECTO parasites Class Cestoda (Tapeworms) – “Girdle form”Endo parasitic

12. 12 1. Class Turbellaria Eye spots-OCELLI Cilia and slime surface Regenerate if cut in two Most are free-living Found in ponds, streams and hot springs “FRESHWATER” 6 species of terrestrial ones in U.S.

13. Planaria Carnivorous Use a pharynx tube to eat Regenerative properties Chemoreception with auricles Light sensitive ocelli 13

14. 14 Turbellaria Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Planaria-Dugesia “Ocelli”

15. 15 2. Class Trematoda “Clonorchis”Clonorchis” Chinese liver fluke Flukes Adults-Endoparasites of vertebrates/several hosts Holdfast devices –Hooks/suckers –Glands produce cyst material Complex life cycle Sense organs are poorly developed

16. SubClass - Digenea “means double-race a.Indirect life cycle 1 st intermediate host = mollusk (snail) Final host = vertebrate b. Tissue attacked: digestive, respiratory, circulatory, urinary, reproductive 16

17. 17 Asian Liver Fluke

18. 18 Clonorchis sinensis Oral suckerIntestineUterusYolk gland TestesOvarySeminal recepticle Asian Liver Fluke

19. 19 Clonorchis sinensis Human/Asian Liver Fluke also infects dogs, cats, pigs 50 million people China, Japan, SE Asia Live in bile duct can cause Cirrhosis of liver Diarrhea, Edema, Pain Controlled by killing snails Gotten by eaten UNDERCOOKED or raw fish

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21. General Life Cycle 21 A.Egg passes in feces to water B.Egg hatches into larva called MIRACIDIUM C.Miracidium finds snail, penetrates skin forms SPOROCYST D. Inside snail, sporocyst produces REDIA asexually E. Redia produce CERCARIA with tails F.CERCARIA emerge from snail and penetrate a second host OR land on vegetation to form METACERCARIA(juvenile flukes) G. Adult grows from metacercaria into JUVENILES when EATEN by the CORRECT DEFINITIVE HOST These are SERIOUS parasites of humans and domestic animals

22. 22 Fasciola hepatica Sheep liver fluke Sheep, cattle and man –Weight loss Eat vegetation with metacercaria “Sheep Liver Fluke”Sheep Liver Fluke

23. 23 Life Cycle of the Sheep Liver Fluke Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

24. 24 Fasciolopsis buski Intestinal fluke 10 million people Man and pigs Hemorrhage and abscesses of small intestine

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26. 26 Paragonimus westermani Lung fluke Carnivores, pigs, rodents and man May be fatal

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29. 29 Schistosoma Blood flukes 200 million people 1 million deaths/year

30. 30 Life Cycle of a Schistosome FlukeSchistosome Fluke Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

31. Blood Flukes(SchistosomaBlood Flukes(Schistosoma) Causes the disease – “Schistosomis” which infects over 200 million people in Africa, S. America and the Middle East. Swim from snails to penetrate skin of humans to liver, intestines, bladder and form ULCERS, ABSCESSES, BLOOD IN Stool and ABDOMINAL Pain. Worst = eggs that clog organs Causing pain in urination, cirrhosis of the liver, 31

32. 32 Schistosome Cercaria have forked tail “Blood fluke”

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34. 34 Swimmers Itch – found in Great Lakes Schistosome dermatitis = Itching but little harm

35. 35 3. Class Monogenea One host Ectoparasites –Mainly fish Opisthaptor –Attachment to host

36. Class Monogenea Found on fish gills Bladders of frogs, salamanders Eyes of hippos Direct life cycle – Single host 36

37. 37 4. Class Cestoidea Tape worms No digestive system 40 feet long Structures: Scolex, proglottid, strobila Monoecious 1000 species known Two host species

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39. 39 Scolex “Head attachment”

40. 40 Proglottid Uterus Testes Ovary Yolk gland Vas deferens Seminal receptacle “Packet of reproductive cells”

41. 41 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pork Tapeworm Pork Tapeworm (Taenia solium) More dangerous Than beef Tapeworm because Cysticerci can Breakoff and go To many organs Like eyes and Brain resulting in Blindness or death

42. 42 Taenia saginata “ Beef tapeworm ” Beef tapeworm Can reach Over 2000 Proglottids Embryos can Live for up to 5 months

43. 43 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Source: Redrawn From Centers for Disease Control, Atlanta, GA. Life Cycle of the Broad Fish Tapeworm Diphyllobothrium latum

44. 44 Fish Tapeworm – Diphllobothrium latum LONGEST TAPEWORM TO INFECT HUMANS 65 feet long Gotten from eating RAW fish/undercooked US infections are MOST common in GREAT LAKES area Worm may cause SERIOUS anemia

45. 45 Dipylidium caninum “Dog tapeworm”Dog tapeworm

46. 46 Echinococcus Echinococcus granulosus Parasite of dogs –Host Juveniles in sheep, man and other mammals –Intermediate host Hydatid cyst

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48. 48 Hydatid Cyst Cysticercus –Juvenile stage –Grows slowly in dogs up to 20 yrs –Filled with 1000’s of scolex’s –Surgical removal

49. 49 Adult stage in dog Echinococcus granulosus

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