1. Phylum Annelida

2. Characteristics  Protostomia, eucoelomates  Metamerism (= unspecialized segmentation)  In the Classes:  Parapodia  Clitellium

3. Systems IntegumentIntegument- epidermis is one cell layer with mucous gland that secrete a moist cuticle. SkeletalSkeletal -hydrostatic (using coelom) MuscleMuscle- longitudinal and circular muscles Each segments muscles are independent of the other segments. DigestiveDigestive- complete, complex, with typhlosole for absorption and chloragogen cells acting as digestive gland and excretory cells.

4. Systems (continue) ExcretoryExcretory- a pair of nephridia per segment. RespiratoryRespiratory -through skin, some through parapodia; tubeworms have gills. CirculatoryCirculatory- closed system, use hemoglobin as oxygen carrier. NervousNervous- dorsal brain; ventral, double, solid nerve cord, with ganglia in each segment. EndocrineEndocrine- hormones secreted by nervous system. ReproductiveReproductive-  Dioecious (Separate Sexes) Male and Female in Polychaeta; no special organs, posterior end becomes gonads.  Monoecious (Contains both Eggs and Sperm) in Oligochaeta and Hirudinea; Clitellium.

5. Annelida Taxonomy Phylum Annelida (an-nel-i-da)  Class Polychaeta (poly-key-ta) Nereis, Aphrodita, Chaetopterus, Arenicola, AmphitriteNereisAphroditaChaetopterus, Arenicola, Amphitrite  Class Oligochaeta (ol-e-go-key-ta) Lumbricus, TubifexLumbricus  Class Hirudinea (hi-ru-din-e-a) Hirudo, leechHirudo Earthworm dissection Click on any term that is underlined to go to that slide

6. Nereis (clam worm) Nereis Return to taxonomy

7. Aphrodite (sea mouse) ventral dorsal Return to taxonomy

8. Other Polychaetes Chaetopterus Arenicola (Lug worm) Amphitrite (plum worm) Return to taxonomy

9. Hirudo (leech) Return to taxonomy

10. Lumbricus dorsal ventral clitellium Return to taxonomy

11. Earthworm Dissection Return to taxonomy Cross section

12. Earthworm cross section Return to taxonomy