Invertebrates

Invertebrates

1. Annelids

   • Examples
     • Earthworms
     • Bearded Fireworm
   • Characteristics
     • soft bodies
     • segmented
     • have paddle-like extensions
       • Purpose: Moving
     • some live in freshwater and soil
     • most live in the sea
     • have chaetae = bristles
       • Purpose: making contact with mud/soil

2. Molluscs

   • Examples
     • slugs
     • squids
     • Snails
     • clams
   • Characteristics
     • soft bodies
     • have 1 or 2 shells
       • Purpose
         • for protection
         • avoid excessive water loss
     • not segmented
     • have a 'muscular' foot
       • Purpose: Moving/burrowing

3. Nematodes

   • Examples
     • Ascaris lumbricoides
     • some parasites
   • Characteristics
     • no obvious head
     • thread-like bodies - taper at mouth & anus
     • live in soils, water and (some) inside another animal