1. WORMS

3. FLATWORMS =“Platyhelminthes”
Planaria – free living
Tapeworms - parasitic
Flukes - parasitic

4. PLANARIA Free living/aquatic ACOELOMATES (NO body cavity)
No TEGUMENT or CUTICLE
DIGESTIVE/CIRCULATORY
Combined gastrovascular cavity
Only 1 opening to digestive system
Mouth at end of tube in middle of body

5. PLANARIA NERVOUS Cerebral ganglia with 2 nerve cords
Eyespots can detect light
Simple learning
EXCRETORY
FLAME CELLS remove excess water
RESPIRATORY
Exchange gases through skin

6. PLANARIA REPRODUCTIVE
Hermaphrodites trade sperm with other worms lay eggs in protective sac on rocks
Ability to regenerate (regrow lost parts)
can be used to reproduce asexually

7. TAPEWORMS Parasites that live in the intestines of all vertebrates
Scolex with hooks and suckers on anterior end help it hold on

8. TAPEWORMS ACOELOMATES
TEGUMENT- Protective covering made of cells Resists digestive enzymes/fools immune system
NO DIGESTIVE SYSTEM/no mouth absorb nutrients that you digest through their skin
EXCRETORY/NERVOUS SYSTEM Similar to Planaria but no eyes

9. TAPEWORMS REPRODUCTIVE
Hermaphrodites- can fertilize self or trade sperm with other worms
Grow by adding PROGLOTTIDS which contain both male and female reproductive organs
30 foot worm can have 2000 proglottids

10. PARASITIC WORMS Adult lives and reproduces in PRIMARY HOST
Larval form lives in INTERMEDIATE HOST

11. HOW DO THEY INFECT HUMANS?
Primary host:
Human
Intermediate host: cow

12. FLUKES Parasites No coelom Leaf shaped body
Covered by TEGUMENT for protection

13. FLUKES DIGESTIVE/CIRCULATORY
Anterior/Posterior suckers help it hold on
1 opening into a gastrovascular cavity
NERVOUS
Cerebral ganglia with 2 nerve cords but no eyes

14. FLUKES REPRODUCTIVE Most hermaphrodites/some separate sexes
Fertilized eggs leave body
in feces or urine
Complicated life cycle with 2 hosts Adults- sexual reproduction Larva – asexual reproduction

15. HOW DO THEY INFECT HUMANS?
Primary host: Human
Larva burrow into skin
Intermediate host: snail

16. ROUND WORMS “NEMATODES”
Ascaris
Trichinella
Hookworms
Pinworms
Filarial worms

17. ROUND WORMS “NEMATODES”
Many free living/some parasites
PSEUDOCOELOMATES – body cavity only lined on one side with mesoderm
Covered with CUTICLE(non-cellular) for protection
2 separate sexes

18. ROUND WORMS “NEMATODES”
REPRODUCTIVE Separate sexes
DIGESTIVE
Digestive tract with 2 openings like Earthworms

19. ROUND WORMS “NEMATODES”
Ascaris – enter by contaminated food/water
live in intestines
only 1 host
Trichinella – enter by eating meat with cysts
live in intestine
Pork host- causes Trichinosis

20. ROUND WORMS “NEMATODES”
Hook worms – live in intestine
release eggs in feces
larva burrow into feet
Pinworms – Most common in U.S.A.
live in lower digestive system females migrate out at night to lay eggs on skin infected by ingesting eggs

21. ROUND WORMS “NEMATODES”
ELEPHANTIASIS
worms live in lymph system
blockage causes limbs to swell
transmitted by mosquitoes
Dog heartworm is also a filarial worm

22. SEGMENTED WORMS “Annelids”
COELOMATES
CUTICLE covers
body for protection

23. SEGMENTED WORMS “Annelids”
DIGESTIVE
digestive system with 2 openings
EXCRETORY
NEPHRIDIA remove water/nitrogen waste
RESPIRATORY
Exchange gases through skin

24. SEGMENTED WORMS “Annelids”
REPRODUCTIVE
Hermaphrodites-
exchange sperm with partner
Lay eggs in mucous sac left on ground

25. SEGMENTED WORMS “Annelids”