1. CRAYFISH DISSECTION

4. Animal Groups Image from: http://ology.amnh.org/biodiversity/treeoflife/pages/graph.html

6. Arthropods

10. All animals with an EXOSKELETON must MOLT (shed their exoskeleton) to grow bigger

11. SEGMENTED BODY like earthworms

15. COMPOUND EYE HAS MULTIPLE LENSES

16. ANTENNAE - touch, taste ANTENNULES - touch, taste, & equilibrium

17. Statocyst

19. SWIMMERETS (5 pair)

20. SWIMMERETS Aid in reproduction In males – transfer sperm In females – carry eggs/young Create water currents

22. MAXILLA – Manipulate food

23. LAST PAIR of MAXILLA = “BAILERS” Keep water moving over gills

24. MANDIBLE

26. APPENDAGES ANTENNA Touch, taste ANTENNULE Touch, taste, equilibrium MANDIBLE Chew food MAXILLA Manipulate food Last pair “bailers”- Move water over gills MAXILLIPEDS Touch, taste, manipulate food CHELIPED Capture food, defense WALKING LEGS Locomotion, move water over gills SWIMMERETS Move water over EGGS, transfer sperm (males) carry young/eggs (females) UROPOD Propulsion during tailflips

28. SWIMMERETS MALES Top pair make a “ V”

29. Females “ in berry ” carry developing embryos on swimmerets

31. INDIRECT DEVELOPMENT MOLLUSKS ECHINODERMS CRUSTACEANS TROCHOPHORE BIPINNARIA NAUPLIUS

32. Examine the inside of your crayfish

35. What keeps water moving over gills? “ BAILERS” WALKING LEGS: are attached to gills so walking moves water Image from: http://www.aa.psu.edu/div/mns/biology/crayfish/crayfishtable.htm

36. INTERNAL Heart Stomach Digestive gland

38. OSTIA

39. ADDUCTOR MUSCLES run mouthparts

40. PYLORIC CARDIAC STOMACH

41. GASTRIC MILL “teeth” inside stomach

43. GONADS (produces sex cells)

45. ABDOMEN INTESTINE (#4) – finish digestion; absorb nutrients; collect & remove feces

47. NERVOUS SYSTEM like earthworms VENRAL NERVE CORD CEREBRAL GANGLIA (brain) GANGLIA along body

48. VENTRAL NERVE CORD

50. Brain Brain

52. THE END