The document discusses the phylum Annelida, or segmented worms. It describes their characteristics, such as being hermaphroditic and having a true coelom. It then discusses different classes of annelids, including Polychaeta (marine fanworms and free-swimming worms), Oligochaeta (earthworms), and Hirudinea (leeches). For earthworms specifically, it outlines their movement, excretion, digestion, respiration, circulation, response, and reproduction systems.

1. PHYLUM ANNELIDA

2. ANNELIDA=> “ segmented worms” often hermaphroditic True coelom Digestive tract

3. ANNELIDA=> most marine species in class: Polychaeta either free-swimming or “fanworms”

4. ANNELIDA=> fanworms are tube-dwellers that have tentacles for filter-feeding

5. “ Christmas Tree” worms

6. ANNELIDA=> free-swimming annelids have a pair of parapodia on each segment usually powerful, pincherlike jaws: (sandworms & clamworms)

7. ANNELIDA - “fireworm”

8. ANNELIDA - “clamworm”

9. The EARTHWORM: Class: Oligochaeta

11. The EARTHWORM: MOVEMENT: 1) posterior setae anchor 2) circular muscles contract 3) anterior setae anchor 4) circular muscles relax and longitudinal muscles contract *muscles contract against “hydrostatic skeleton”

13. The EARTHWORM: EXCRETION: NEPHRIDIA - long tubules that excrete liquid waste

14. The EARTHWORM: DIGESTION: “ MOUTH” (opening) PHARYNX (acts as a soil pump) CROP (temp. storage organ) GIZZARD (grinds up soil) INTESTINE (nutrients are absorbed) ANUS (exit)

15. The EARTHWORM:

17. The EARTHWORM: RESPIRATION & CIRCULATION: no special resp. structures breathe through moist skin blood flows from anterior (ventral blood vessel) to posterior (dorsal blood vessel) AORTIC ARCHES - 5 pairs of muscular vessels at ant. end “hearts”

20. The EARTHWORM: RESPONSE: small “brain” of fused GANGLIA ventral nerve cord poor sensory organs

21. The EARTHWORM: REPRODUCTION: are hermaphrodites cannot fertilize own eggs young hatch in 2 - 3 weeks

22. LEECHES: Class: Hirudinea have no setae nor parapodia most are parasites most dwell in fresh water

23. LEECHES: Class: Hirudinea one pair suckers muscular pharynx w/ razor-sharp teeth anti-coagulant & pain-numbing saliva