1. ECHINODERMS
Phylum Echinodermata

2. What is an Echinoderm? Spiny skinned marine invertebrates
Endoskeleton (calcium carbonate)
Water vascular system
Suction-cup like tube feet
Radial symmetry (pentaradial)
2 digestive openings
Coelomates
All 3 germ layers

3. Water Vascular System Unique to Echinoderms
System of internal tubes filled with fluid that aids in respiration, circulation, and movement.
Like a hydraulic system

6. Classes of Echinoderms
There are about 7,000 living species and 13,000 extinct species.
Divided into 5 main classes:
1)class Asteroidea
2)class Crinoidea
3)class Ophiuroidea
4)class Echinoidea
5)class Holothuroidea

7. Class Asteroidea
Sea stars (starfish)

8. Class Crinoidea
Sea lillies, feather stars

9. Class Ophiuroidea
Brittle stars, basket stars

10. Class Echinoidea
Sea urchins, sand dollars

11. Class Holothuroidea
Sea cucumbers

12. Ecology of Echinoderms
Population control of algae and bivalves
Threat to coral reefs (crown of thorns)
Food for many marine animals