1. Worms
Friend OR Foe ?

2. Invertebrate protostomes Elongated bodies Bilateral symmetry
CHARACTERISITCS
OF ALL WORMS
Invertebrate protostomes
Elongated bodies
Bilateral symmetry
Cephalization
Cerebral ganglia “brain”
No respiratory organs
(Breathe through skin)

4. WHERE DO THEY LIVE? _______________ - Found in environment
_______________ -
Found in environment
_______________
Live on or in another organism
FREE LIVING
PARASITIC

5. PARASITIC WORMS Animal host where ADULT feeds and
reproduces = ______________HOST
Animal host where LARVAL form
lives and feeds = ______________ HOST
PRIMARY
INTERMEDIATE

6. FLATWORMS PHYLUM: Platyhelminthes
FREE LIVING PARASITIC
Planaria Flukes & Tapeworms

7. ALL FLATWORMS are ACOELOMATES!
PLATYHELMINTHES (Flatworms)
ALL FLATWORMS are ACOELOMATES!

8. PLANARIA NOT PARASITES http://www.quia.com/jg/352695list.html

9. ONE opening digestive system
GASTROVASCULAR CAVITY (Combination Digestive & circulatory)

11. EXCRETORY FLAME CELLS collect excess water and nitrogen waste
Excreted through pores in skin
Moving cilia look like little “flames”

12. REPRODUCTION
SEXUAL-
HERMAPHRODITES (have both ovary & testes in one organism) but trade with a partner
ASEXUAL-
can use regeneration to
grow a new organism from part of parent worm

13. PARASITIC FLATWORM Schistosoma
NOT IN USA but infects over 250 million people worldwide
Worms can block blood vessels to organs causing irritation, bleeding, tissue decay producing disease called
= __________________
SCHISTOSOMIASIS

14. HUMAN BLOOD FLUKE Schistosoma
HUMAN BLOOD FLUKE Schistosoma
Adult worms mature & reproduce in blood vessels; eggs travel to intestines or bladder
Immature worms burrow through skin into blood vessels
Larvae grow tails and leave snail
Eggs leave body in urine or feces
Larva hatches from egg & infects snail (intermediate host)

15. TAPEWORMS PARASITIC FLATWORM that lives in HOST animal intestines
TAPEWORMS
Dog tapeworm
PARASITIC FLATWORM that lives in HOST animal intestines

16. TAPEWORM VOCAB
SCOLEX
____________- Head with suckers and hooks to help hold on inside host

17. TAPEWORM VOCAB ___________________- PROGLOTTIDS
hermaphroditic reproductive structures
(contain both male & female sex organs)
Contain fertilized
eggs
Shed in feces

18. WORM VOCAB TEGUMENT CUTICLE
______________ Thickened PROTECTIVE layer on the outside of worms made of CELLS
_______________
NON-CELLULAR PROTECTIVE coating found on the outside of worms
CUTICLE

19. Attaches with SCOLEX

20. TAPEWORM NO DIGESTIVE SYSTEM -absorbs nutrients through skin
NO DIGESTIVE SYSTEM
-absorbs nutrients through skin
TEGUMENT protects them from host digestive enzymes and immune system

21. TAPEWORMS Can grow up to 30 ft (2000 proglottids)
TAPEWORMS
Can grow up to 30 ft
(2000 proglottids)
REPRODUCE WITH PROGLOTTIDS
Add new proglottids behind scolex
Mature ones drop off at tail end
Leave body in feces

22. EX: BEEF TAPEWORM Adults attach inside intestines and absorb
digested food
Humans eat undercooked meat
containing cysts
Proglottids burst releasing eggs with larvae inside on ground
Proglottids are released in feces
Cows eat grass; larvae travel through blood vessels;
make cysts in muscle

23. ROUND WORMS Phylum: Nematoda
Ascaris
Trichinella
Hookworms
Pinworms
Filarial worms

24. ALL ROUND WORMS are PSEUDOCOELOMATES
NEMATODA (Round worms)
ALL ROUND WORMS are PSEUDOCOELOMATES

25. ROUND WORM Ascaris PARASITIC Have a 2 OPENING digestive system
ROUND WORM
Ascaris PARASITIC
Have a 2 OPENING
digestive system
Lives in intestines
Feeds on passing food

26. Females can grow up to 1 ft long & produce 200,000 eggs/day
Humans become infected when they
eat FOOD or WATER
contaminated with
eggs
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27. Most common worm infection WORLD WIDE
Most common worm infection WORLD WIDE
Mostly in children
Estimated 25%
of world’s
population is infected with Ascaris

28. ROUND WORM Trichinella
Cysts release larvae that burrow into intestinal wall & mature
Humans infected by eating undercooked meat containing cysts  
Larvae forms cysts in muscle
Adults release larvae that travel through bloodstream to muscles 

29. Trichinella
Trichinella infection can lead to disease called = __________________
TRICHINOSIS-
Symptoms:
Muscle pain & stiffness Can be fatal if cysts form in heart

30. TRICHINOSIS Less than 100 cases/year in USA from PORK
Most from eating wild game
Curing (salting), drying, smoking, or microwaving meat does not consistently kill infective worms.

31. PARASITIC ROUND WORMS Guinea worm
Found in AFRICA

32. PARASITIC ROUND WORMS Guinea worm 
Blisters pop and larvae are released in water 
Female bodies under skin fill with eggs and break open; larvae form blisters
Larvae eaten by small crustaceans Humans infected by drinking water  
Larvae mature and adult worms migrate to skin

33. FILARIAL ROUNDWORMS
are transmitted by insects

34. DISEASES caused by FILARIAL ROUND WORMS
DOG HEARTWORM
Elephantiasis
Loa Loa - eye worm

35. FILARIAL ROUND WORMS DOG HEARTWORM Carried by mosquitoes

36. DISEASES caused by FILARIAL ROUND WORMS
Elephantiasis
Adult worms live in lymph nodes causing blockage so fluid back ups

37. ELEPHANTIASIS Common in tropical countries
Adult worms can grow to 4” long

38. ELEPHANTIASIS

39.   Mosquito picks up larvae from blood when it feeds
Larvae develop into juveniles inside mosquito
Mosquito injects juveniles which migrate to lymph nodes and mature
Adult worms live
and reproduce in
lymph vessels  

40. FILARIAL ROUND WORMS Loa loa
Found in AFRICA

41. Loa Loa worm Humans are infected with larvae when bitten by loa fly
Larvae mature & crawl around under skin (especially near face)
Adults mate and produce larvae which can be picked up by another fly and transmitted to another person

42. PARASITIC ROUND WORMS Hookworms
Live in intestine;
feed on BLOOD
Ancylostoma

43.      HOOKWORM LIFE CYCLE Return to intestines; mature & mate
Larvae are coughed up & swallowed;   
Adult worms live in intestine and feed on blood
Larvae enter body by burrowing through skin on feet & travel to lungs  
Eggs leave body in feces and hatch as larvae in soil

44. Hookworms in Humans PROBLEMS caused by migrating larvae
Cause intense reaction in skin at site
Infect 40 million people worldwide

45. Parasitic ROUND WORMS Pinworms
Most common parasitic infection IN UNITED STATES
1/5 children are infected
Worldwide 500 million people are infected with pinworms
Grow up to ½ inch long

46. Parasitic ROUND WORMS Adult Pinworms live in intestine
Females crawl out through anus at night and lay 15,000/day eggs on skin
Intense itching causes host to scratch
Eggs under fingernails and on hands are spread back to self or to others when objects/food are touched

47. ALL SEGMENTED WORMS are EUCOELOMATES! “True coelom”
(PHYLUM: ANNELIDA)
ALL SEGMENTED WORMS are EUCOELOMATES! “True coelom”

48. SEGMENTED WORMS Annelida
FREE LIVING PARASITIC
Earthworms Leeches

49. SEGMENTED WORMS Earthworms play an important role in soil fertility
Return nutrients to soil by decomposing dead leaves and organic matter
Burrowing allows air and water to penetrate to roots
Tunnels loosen soil so roots can grow more easily
“intestines of the earth”
-Aristotle

50. PARASITIC SEGMENTED WORMS LEECHES
Medical uses