1. Echinoderms & Chordates

2. Phylum Echinodermata (echinoderms)
About 6,000 species
All _______________

3. Phylum Echinodermata (echinoderms)
Eucoelomates, triploblastic

4. Phylum Echinodermata (echinoderms)
Eucoelomates, triploblastic
Pentamerous (5-part) radial symmetry as adults
Parts arranged around oral/aboral axis

5. Phylum Echinodermata (echinoderms)
Why not in ___________? Larva bilaterally symmetrical!

6. Phylum Echinodermata (echinoderms)
Calcareous endoskeleton. Plates form surrounded by tissues.
Arises from mesoderm. “echino-” means spiny, “-derm” means skin.

7. Phylum Echinodermata Water vascular system in _____________
Connect to tube feet
Note madreporite on aboral surface of starfish (takes water into system)

8. Phylum Echinodermata
Tube feet in action

9. Phylum Echinodermata (echinoderms)
Complete digestive system
Reproduction: have good regeneration abilities, some can break into parts and reproduce asexually.

10. Phylum Echinodermata (echinoderms)
Most reproduce sexually
Dioecious, fertilization external

11. Phylum Echinodermata No head or well developed brain (nerve ring)
No excretory organs (no flame cells, nephridia, etc.)
No respiratory system (tube feet and papulae help exchange gases)

12. Phylum Echinodermata (echinoderms)
Deuterostomes

13. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Class Asteroidea (sea stars)
Class Ophiuroidea (brittle stars)
Class Echinoidea (sand dollars and sea urchins)
Class Holothuroidea (sea cucumbers)

14. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Sessile for some or all of life. Add new __________ as they grow.
Have mouth and anus on upper surface.

15. Phylum Echinodermata Class Crinoidea (sea lilies/feather stars)
Glorious fossil past (6000 fossil species, 600 living ones).
Wisconsin

16. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Class Asteroidea (sea stars)
Class Ophiuroidea (brittle stars)
Class Echinoidea (sand dollars and sea urchins)
Class Holothuroidea (sea cucumbers)

17. Phylum Echinodermata (echinoderms)
Class Asteroidea (sea stars)
1500 species. Active and important marine predators
Move about on tube feet

18. Phylum Echinodermata (echinoderms)
Class Asteroidea (sea stars)
Predation may cause problems
Ex, crown of thorns starfish (coral predator)

19. Phylum Echinodermata (echinoderms)
Class Asteroidea (sea stars)
The rest of the story: part of problem may be overcollecting of tritons, a gastropod that preys on these starfish

20. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Class Asteroidea (sea stars)
Class Ophiuroidea (brittle stars)
Class Echinoidea (sand dollars and sea urchins)
Class Holothuroidea (sea cucumbers)

21. Phylum Echinodermata (echinoderms)
Class Ophiuroidea (brittle stars)
2000 species. Abundant, nocturnal. Move using two arms at a time
Feed on plankton and organic debris with tube feet.

22. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Class Asteroidea (sea stars)
Class Ophiuroidea (brittle stars)
Class Echinoidea (sand dollars and sea urchins)
Class Holothuroidea (sea cucumbers)

23. Phylum Echinodermata Class Echinoidea (sea urchins/sand dollars)
Lack arms species. Endoskeleton of fused calcareous plates
No arms or rays. Have rows of spines and tube feet. Spines and feet moveable.

24. Phylum Echinodermata (echinoderms)
Class Echinoidea (sea urchins/sand dollars)
Sea urchins: long spines
Sand dollars: short spines

25. Phylum Echinodermata (echinoderms)
Class Echinoidea (sea urchins/sand dollars)
Pedicillariae. Discourage small invertebrates from settling on surface.

26. Phylum Echinodermata (echinoderms)
Class Echinoidea (sea urchins/sand dollars)
Aristotle’s lantern: complex chewing apparatus.

27. Phylum Echinodermata Can be important members of marine ecosystems
Ex, sea urchins as herbivores

28. Urchins, sea otters, and kelps
Sea otters hunted almost to extinction on West Coast
Now expanding back
Top carnivores (almost): eat mussels, abalone, sea urchins.
Purple sea urchin

29. Urchins, sea otters, and kelps
Urchins eat __________ of kelp
Fewer urchins now that otters are back.

30. Urchins, sea otters, and kelps
Giant kelp forests recovering as otters return.
Fish and other associates rebounding.

31. Sea urchins
Eggs (roe) edible, delicacy (known as uni in sushi bars)

32. Phylum Echinodermata (echinoderms)
Class Crinoidea (sea lilies/feather stars)
Class Asteroidea (sea stars)
Class Ophiuroidea (brittle stars)
Class Echinoidea (sand dollars and sea urchins)
Class Holothuroidea (sea cucumbers)

33. Phylum Echinodermata Class Holothuroidea (sea cucumbers) Elongate
Soft bodied (endoskeleton plates reduced or absent)
Often with feeding tentacles around mouth

34. Phylum Echinodermata Class Holothuroidea (sea cucumbers)
Have respiratory organ (respiratory tree) (11, F), arising from cloaca (12, G: near anus, 13)
Gonads (8, H)
Intestine (10, I)

35. Phylum Echinodermata Class Holothuroidea (sea cucumbers)
Symbiosis story: black pearlfish can be found living in _________ of sea cucumbers

36. Phylum Echinodermata Class Holothuroidea (sea cucumbers)
Sea cucumber defense tactic: regurgitate internal organs and _____________ them later

37. Phylum Echinodermata (echinoderms)
Class Holothuroidea (sea cucumbers)
Edible: braised sea cucumber with tea leaves

38. Phylum Chordata (chordates)
About 43,000 species
Triploblastic, eucoelomates

39. Phylum Chordata (chordates)
Bilateral symmetry
Deuterostomes

40. Segmentation
Present in chordates
Often visible in embryo

41. Internal skeleton
Differs from echinoderms. Rodlike, deeper in body. Gives attachment points for muscles.
Human skeleton

42. 4 Key Features
1) Hollow (tubular!) nerve cord under *dorsal* surface

43. 4 Key Features 1) Hollow (tubular!) nerve cord under *dorsal* surface
Becomes brain and spinal cord
*Invertebrates usually have ventral nerve cords.

44. 4 Key Features
2) Notochord: flexible rod just under nerve cord. Originally served as muscle attachment point

45. 4 Key Features 3) Pharyngeal pouches in embryo
In humans, only one remains to form Eustachian tubes connecting inner ear to __________.

46. 4 Key Features
4) Postanal tail (at least during embryonic stages). Nearly all other animals with terminal anus

47. Chordate survey Subphylum Urochordata (tunicates)
Subphylum Cephalochordata (lancelets)
Subphylum Vertebrata (vertebrates)

48. Chordate survey Subphylum Urochordata (tunicates)
Marine species.

49. Chordate survey Subphylum Urochordata (tunicates)
Adult sessile, filter feeder.
Has holdfast, siphons (incurrent & excurrent, pharynx). Cilia in pharynx create water current.

50. Chordate survey Subphylum Urochordata (tunicates)
Pharynx used to feed, traps food in mucus on endostyle
Pharynx has gill slits for breathing
Many adults secrete tunic: tough sac of ______________ around body.

51. Chordate survey Subphylum Urochordata (tunicates)
Subphylum Cephalochordata (lancelets)
Subphylum Vertebrata (vertebrates)

52. Chordate survey Subphylum Cephalochordata (lancelets)
Marine. 20 species.
Ex, Amphioxus or Branchiostoma

53. Chordate survey Subphylum Cephalochordata (lancelets)
Filter feeder, can swim
Oral hood has tentacles (sensory)
Cilia create water current, used for breathing and filter feeding. Water exits via _________________.

54. Chordate survey Subphylum Cephalochordata (lancelets)
No head, brain, eyes, etc.
Skin only 1 cell layer thick (vertebrates with multi-layered skin)
________________: segmented muscles.

55. Chordate survey Subphylum Cephalochordata (lancelets)
Model version (as seen in lab)

56. Chordate survey Subphylum Urochordata (tunicates)
Subphylum Cephalochordata (lancelets)
Subphylum Vertebrata (vertebrates)

57. Subphylum Vertebrata (vertebrates)
Distinctive features
1) Have vertebral column. Bony segments replace __________, enclose spinal cord

58. Subphylum Vertebrata (vertebrates)
Distinctive features
2) Have well-developed head (with skull and brain)

59. Subphylum Vertebrata (vertebrates)
Other features
3) Neural crest in embryo. Cells migrate to form many tissues (parts of muscle, nerve, skin, systems, etc.) in various places in body.

60. Subphylum Vertebrata (vertebrates)
Other features
4) Internal organs: liver, kidneys, endocrine glands, heart and closed circulatory system
5) Endoskeleton of _________ (protein) or bone (protein and calcium crystals). Bone strong but not brittle. Can make big bodies this way.

61. Chordate survey Subphylum Vertebrata (vertebrates) Class Agnatha
Class Chondrichthyes
Class Osteichthyes
Class Amphibia
Class Reptilia
Class Aves
Class Mammalia