1. ANNELIDA

2. Characteristics Segmented worms Segmented worms Earthworms, leeches, polychaetes Earthworms, leeches, polychaetes Annelida means “little rings” Annelida means “little rings” Most complex body structure of all worms Most complex body structure of all worms

3. Anatomy Setae- bristles on worms Setae- bristles on worms Nerve cord- long string of nerve tissue Nerve cord- long string of nerve tissue Coelomates - One way digestive system- mouth to anus Coelomates - One way digestive system- mouth to anus Closed circulatory system Closed circulatory system

4. Anatomy Takes in oxygen and gives off carbon dioxide directly through moist skin Takes in oxygen and gives off carbon dioxide directly through moist skin Two sets of muscles to help it move Two sets of muscles to help it move No skeletal system No skeletal system Earthworm poop is called castings, fertilizes the soil Earthworm poop is called castings, fertilizes the soil Excrete liquid waste through pores called nephridia Excrete liquid waste through pores called nephridia

5. Feeding Eats soil, obtains nutrients Eats soil, obtains nutrients Omnivores - eat organic matter and algae Omnivores - eat organic matter and algae Some are scavengers, blood suckers, filter feeders, predators Some are scavengers, blood suckers, filter feeders, predators Leeches suck blood from its host Leeches suck blood from its host

6. Reproduction Sexually and asexually Sexually and asexually Asexually - used by some worms Asexually - used by some worms Back end of worm breaks off and forms a new worm Back end of worm breaks off and forms a new worm Sexually - earthworms are both male and female- hermaphroditic Sexually - earthworms are both male and female- hermaphroditic

7. Habitat Soil, marine, freshwater Soil, marine, freshwater Niche- earthworms tunnel Niche- earthworms tunnel This loosens the soil and aerates so water and plant roots can move This loosens the soil and aerates so water and plant roots can move Polychaetes are marine Polychaetes are marine What are some biotic and abiotic factors? What are some biotic and abiotic factors?

8. Adaptations Setae are adapted to environment Setae are adapted to environment Leg-like in rocky areas Leg-like in rocky areas Paddle-like in soil for digging Paddle-like in soil for digging