Annelids

Annelids

1. Niche

   • Live in Narrow Spaces
     • burrow in soft mud or soil
     • live in crevices between rocks
     • make tubes of calcium carbonate
     • advantages
       • protection from predators
       • easy access to water
     • disadvantages/challenges
       • mobility suppressed

2. Body Plan/Structure

   • General Body plan of annelids
     • bilateral symmetry
     • long round shape
     • segmentation
     • dorsal blood vessel
     • body wall
       • 2 layers of muscles
         • circular muscle
         • longitudinal muscles
     • coelomic cavity
       • fluid filled in live annelid
     • ventral nerve cord

3. Annelid Movement

   • Crawling in Polychaete Annelids
   • Burrowing in Earthworms