1. WARM UP
1. Draw a dissected earthworm, showing the ganglia, nerve cord, hearts, blood vessels, pharynx, crop, gizzard, and intestine.

2. Echinoderms
Phylum Echinodermata

3. Characteristics Echinoderm means “spiny skin” 6,000 marine species
Endoskeleton of ossicles and spines
6,000 marine species
Benthic

4. Structure Exhibit bilateral and radial symmetry
Regeneration of arms
Slow movement
Canals of water-vascular system
Tube feet
Used for movement

5. Feeding Use arms to gather food Most are grazers/scavengers
Sea stars are predators
Use tube feet to pry open oysters, clams, etc.

6. Diversity Class Crinoidea Class Stelleroidea Class Ophiuroidea
Sea lilies
Class Stelleroidea
Sea stars
Class Ophiuroidea
Brittle stars

7. Diversity Class Echinoidea Class Holothuroidea
Sea urchins, sand dollars
Class Holothuroidea
Sea cucumbers

8. WRAP UP
Describe how the tube feet are able to help echinoderms both move and eat.