1. Animal Evolution – Invertebrates Part II

2. NEMATODES Meaning “thread like”, “round” worms

3. NEMATODA Roundworm body plan

4. NEMATODA False coelom Complete digestive system gonad pharynx intestine false coelom eggs in uterusanus muscularized body wall

5. NEMATODA live as free living soil, water, polar regions, tropics parasitic affect plants and animals no internal transport systems simple nervous system

6. NEMATODA reproduction sexual only fertilization takes place inside the body can be hermaphroditic

7. NEMATODA Examples of parasitic diseases: filarial worms causes affected part of body to swell known as elephantitis

8. NEMATODA Filaria have intermediate insect hosts (flies) which infect humans through biting.

9. NEMATODA trichinosis caused from undercooked pork burrow into organs and tissue causes extreme pain

11. T RICHINELLA L IFE C YCLE

12. MOLLUSKS meaning “soft bodied” body Plan foot contains mouth and other structures associated with feeding

13. M OLLUSKS different shapes flat for crawling spade-shaped for burrowing tentacles for capturing prey mantle thin, delicate tissue covering body shell calcium carbonate visceral Mass contains internal organs

14. M OLLUSKS Divided into 3 classes: Gastropods “stomach foot” located on ventral surface, 1 shell contain chemicals that are distasteful or poisonous

15. M OLLUSKS Includes snails slugs

16. M OLLUSKS nudibranchs sea hares

17. Bivalves Filter feeders Examples clams oysters scallops

18. Cephalopods “head-foot” Examples octopus squid

19. cuttlefish nautiluses

20. M OLLUSKS Usually have 8 tentacles equipped sucking disks nautilus have 40 – 90 Lacks a shell defense mechanism speed ink

21. M OLLUSKS structures / systems radula layer of flexible skin lined with teeth respiration aquatic snail, slugs rely on a moist cavity lined with blood vessels

22. M OLLUSKS Internal Transport open circulatory system simple heart pumps blood through the body tissues in open spaces called sinuses must pass through the gills first good for slow moving mollusks closed circulatory system blood always flows through vessels pumped by a heart more efficient for fast moving mollusks

23. M OLLUSKS

24. Excretion anus solid wastes nephridia removes ammonia from blood Reproduction sexual hermaphroditic trochophore free swimming larvae stage Go back to part 1

25. ARTHROPODS meaning “jointed appendages” divided into 4 classes trilobites

26. A RTHROPODS Chelicerates ticks

27. A RTHROPODS Chelicerates (cont.) Spiders Scorpions Horseshoe crabs

28. ARTHROPODS Crustaceans crab shrimp crayfish

29. A RTHROPODS Uniramians centipedes millipedes all insects grasshoppers

30. A RTHROPODS Insects (cont.) bees moths flies

31. 3 most important features of an Arthropod exoskeleton provides protection and is waterproof made of chitin insects flexible and leathery lobsters, crayfish extremely hard

32. A RTHROPODS Jointed appendages used for movement and includes wings legs flippers claws antennae

33. A RTHROPODS segmented bodies head brain thorax legs abdomen internal organs cephalothorax head and thorax fused spiders, crayfish and lobsters

34. A RTHROPODS

35. respiration gills (crustaceans) row of feathers located under the exoskeleton

36. A RTHROPODS book gills (horseshoe crab) and book lungs (spider) layered like pages in a book increases the surface area for gas exchange

37. A RTHROPODS tracheal tubes (terrestrial arthropods) spiracles bring air in through tracheal tubes network of tracheal tubes supplies oxygen to all body tissues by diffusion works well in small animals only internal transport well developed heart pumps blood through an open circulatory system

38. A RTHROPODS blood is pumped from the heart through arteries once the blood reaches the tissues it is no longer kept in the artery the blood now bathes the tissues animal must move its muscles in order to move the blood blood now collects in spaces called sinuses the blood collects in a large cavity around the heart and is pumped back through the body

39. A RTHROPODS excretion Anus solid wastes malpighian tubules dipose of nitrogen wastes becomes concentrated and is added to the undigested food green gland aquatic arthropods poisonous

40. A RTHROPODS Nervous System well developed brain and ganglion highly sensitive picks up Reproduction sexual internal fertilization spiders and some crustaceans male deposits sperm packets that female

41. A RTHROPODS Insect development

42. A RTHROPODS Crab life cycle

43. adult youngegg nymphs egg Growth and molting Incomplete metamorphosis Complete metamorphosis T YPES OF I NSECT D EVELOPMENT larvae pupa Different stages exploit different resources at different times

44. ECHINODERMS meaning “spiny skinned” examples starfish brittle stars sand dollars

45. E CHINODERMS sea urchins sea cucumber

46. E CHINODERMS sea lilies feather stars

47. E CHINODERMS Characteristics no posterior or anterior end primitive nervous system 2 sided oral surface mouth (ventral) aboral surface top (dorsal) internal skeleton larval stages closely related to that of chordates

48. E CHINODERMS

49. Water vascular system

50. E CHINODERMS Systems Water Vascular System madreporite Tube-like structure that opens to the outside connects to ring canal and hundreds of tube feet acts like a hydraulic pump creates a partial vacuum allows tube feet to grasp onto to objects/prey

52. E CHINODERMS digestive use tube feet to pry open prey clams, scallops flips stomach into shell secretes digestive enzymes when finished pulls stomach back into its mouth nocturnal

53. E CHINODERMS

54. Respiration use of thin walled tissue found tube feet skin gills

55. E CHINODERMS internal Transport (circulatory) distribution of nutrients is performed by digestive glands fluid within the body cavity excretion anus solid wastes tube feet and skin gills excrete ammonia wastes

56. nervous nerve ring that surround the mouth radial nerves

57. E CHINODERMS Reproduction Sexual separate sexes produce larvae with bilateral symmetry allow them to swim and feed settle on the ocean floor and mature into adults that have radial symmetry Asexual have the ability to regenerate as long as part of the ring canal is present