Worldwide distribution. Habitat: Saltwater, Freshwater, and Land. Marine. Found in benthic regions and on the surface.

Latin singular: Annulus Plural: Annuli Annelid Metamerization- Division of the body into a series of repeating segments. What other organisms, besides those in this phylum, are metameric? What is the evolutionary advantage to metamerization?

Oligochaeta- Earthworms Hirudinia- Leeches Polychaeta- Freshwater/Marine worms

All Annelids (except leeches) have setae. Setae- Short hairs/bristles. Function: Anchor during movement. Short setae: land Long setae: aquatic Body segments separated by septum Septum: Internal wall Closed circulatory system Well-developed nervous system (brain + nerve cords)

 Hydrostatic Skeleton: A skeleton made up of fluid under pressure in closed compartments. Circular Muscle Longitudinal Muscle Circular Muscle

Contraction of longitudinal muscles- shorten Contraction of circular muscles- lengthen Alternate muscular contractions: longitudinal, circular, longitudinal, circular, etc.

Worm Ranch: shows/dirty-jobs/videos/worm-rancher.htmhttp://dsc.discovery.com/tv- shows/dirty-jobs/videos/worm-rancher.htm Eating a worm: shows/man-vs-wild/videos/whopper-worm.htmhttp://dsc.discovery.com/tv- shows/man-vs-wild/videos/whopper-worm.htm

Sexual & Asexual Polychaets- Dioecious Oligochaetes & Hirudinia- Monecious Clitellum: leeches and earthworms Class Polychaets do not use clitellum for reproduction!

Oligochaetes & Hirudinia- Monecious Clitellum: leeches and earthworms Class Polychaets do not use clitellum for reproduction!

Habitat: Primarily freshwater, few marine. Abundant in tropical regions. Size: Most between 2-6 cm in length. Color: Variety of colors and patterns: black, brown, red, or olive green.

 Monecious.  After fertilization, clitellum secretes a mucous –like cocoon that receives eggs & sperm.  Bury mucous cocoon in mud.  Development process is similar to Oligochaetes.

 Medicinal uses: circulation, anti-clotting (Produces anticoagulant that prevents blood from clotting.)  External parasite with suckers on each end.

 Habitat: mucous-lined burrows near low tide. Most active at night.  Size: Grows up to cm in length.  Diet: Particle feeders. Use cilia or mucus to obtain food. Consume plankton.

 Parapoda: Appendages of Polychaetes. Function: Locomotion & breathing.

Fire-worm

Featherduster-worm

Scale-Worm