1. Earthworm Dissection Photo Credit: All photos taken from http://www.flushing.k12.mi.us/srhigh/mignerey/web%20dissections/earthworm%20web/Frameset.htm http://www.flushing.k12.mi.us/srhigh/mignerey/web%20dissections/earthworm%20web/Frameset.htm Some content from: http://www.scienceclass.com/dissect/teacher_materials/glossary/earthworm_glossary.htmlhttp://www.scienceclass.com/dissect/teacher_materials/glossary/earthworm_glossary.html Various videos from both www.YouTube.com and www.arkive.comwww.YouTube.comwww.arkive.com

2. External Anatomy

3. Cuticle – keeps the worm from drying out

4. Dorsal – top part

5. Ventral – bottom part

6. Clitellum- makes mucus that dries up to form a cocoon

7. Prostomium – covers the mouth of the worm

8. Mouth- opening at the end allowing the intake of food consisting of particles of both living and dead substances

9. Setae – bristle like structures that help the worm move

10. Sperm Duct – openings in which sperm can pass through

11. Sperm groove – sperm moves along here from sperm duct to another worm

12. Oviduct- tube through which eggs pass

13. Anus – where excrement (poop) comes out

14. Internal Anatomy

15. Circulatory System Aortic arches Ventral blood vessel Dorsal blood vessel Go To Nervous System

16. Aortic Arches - surround the esophagus and function in pumping the blood throughout the body

17. Ventral Blood Vessel- carries blood from the aortic arches to the rest of the body

18. Dorsal Blood Vessel- Returns blood to the aortic arches and has valves to prevent backflow

19. Nervous System Ganglion- group of nerves. In the earthworm, there is a pair of ganglia in each segment and a cerebral ganglia acts like a brain

20. Ventral Nerve Cord- connects the ganglia in each segment of its body with the cerebral ganglia. It coordinates movement

21. Excretory System Nephridium- filters wastes. Almost each segment of the worm has a pair of nephridia.

22. Digestive System Food goes from the: Mouth Pharynx Esophagus Crop Gizzard Intestine Anus

23. Pharynx- moves food from the mouth to the esophagus

24. Esophagus- Carries food between the pharynx and the crop

25. Crop – Stores food

26. Gizzard – grinds food

27. Intestine – Digests food

28. Mouth- opening at the end allowing the intake of food consisting of particles of both living and dead substances

29. Anus – where excrement (poop) comes out

30. Reproductive System

31. Seminal vesicles- store sperm produced by the earthworm

32. Seminal receptacles- paired organs that store sperm received from another worm during copulation

33. How do Earthworms Mate? Earthworms are hermaphrodites which means they have both mail and female body parts

34. Worms line up head to tail

35. Slime coats the clitellum

36. both of the earthworms begin to wriggle out of the slime tube

37. As they do this the tube passes over the sperm ducts and picks up sperm

38. Down the sperm groove

39. And mixes with eggs that come out of the oviduct

40. When free of the slime tube, the cocoon closes up and the sperm and eggs mix. This sac is carried by a worm until baby worms have developed, at which point the sac breaks open and they squirm free.