Annelida and Basal Ecdysozoans (Segmented Worms)

  1. Metameric segmentation
    all segments are identical
  2. Setae
    tiny, chitinous bristles that help anchor segments during movement
  3. Hydrostatic skeleton
    can make themselves rigid with muscle contraction
  4. Septum
    seperates segments and allows for very precise movement
  5. Parapodia
    paired appendages in polychaeta
  6. Clitellum
    band like thing on body of worms that is used in reproduction
  7. Superficial Annuli
    ring...
  8. Cuticle
    a nonliving external layer secreted by the epidermis
  9. collagen
    a structural protein present throughout the Metazoa and abundant in vertebrate connective tissue
  10. Cryptobiosis
    state of suspended animation, can stop when environment becomes too dry, they can be dormant then wake up fine later when the environment is fit
  11. Roundworm lifecycle
    • penetrate human skin
    • circulates til it gets to the intestines where it then lays its eggs
    • babies hatch and it starts all over again
  12. Annelida
    • 15,000 species
    • metameric segmentation
    • setae
    • coelom
    • hydrostatic skeleton
  13. Annelida
    • Polychaeta- clamworms, plumed worms, scaleworms, lugworms, etc
    • Oligochaeta- earthworms
    • Hirudinea
  14. Annelida- Polychaeta
    • 10,000 species, mostly marine
    • parapodia
    • setae
    • head with sense organs
    • very mobile
    • sedentary forms
    • suspension feeders
  15. Annelida- Oligochaeta
    • terrestrial and freshwater- 3,000 species
    • earthworms
    • setae
    • hermaphroditic
    • no parapodia
    • clitellum
  16. Annelida- Hirudinea
    • most freshwater, 500 species
    • lost setae
    • superficial annuli
    • hermaphroditic
    • clitellum
    • temporary or permanent ectoparasites
    • suck blood with pharynx
    • secrete numbing chemicals
    • penetrate surface with proboscis
  17. Basal Ecdysozoans characteristics
    • Nematodes have a non chitinous exoskeleton
    • secrete cuticle
    • composed of collagen protein
    • secrete chitin in exoskeleton
    • appendages for locomotion
  18. Onychophora- Velvet-worms
    • about 70 species
    • many pairs of unjointed legs
    • chitin in exoskeleton
    • rich in fossil records
  19. Nematoda- roundworms
    • extremely numerous and diverse- 12,000 species
    • free-living, symbiotic, and parasitic
    • variety of habitats
    • no legs
    • longitudinal muscles only
Author
mphothiwat
ID
240718
Card Set
Annelida and Basal Ecdysozoans (Segmented Worms)
Description
Bio 101 lecture 10 vocab and key terms
Updated