1. Phylum Echinodermata
Spiny Skinned animals

2. Echinoderms– echin (spiny) and derma (skin)
General information

3. Symmetry
Secondary Pentaradial Symmetry– the larvae are bilateral and the adults are radial

4. Body Development
Bilateral larvae
Pentaradial adult.

5. Videos:
starfish eating starfish brittle star moving

6. Water Vascular System
Tube feet: used for feeding, moving, breathing, and even reproduction are extended by taking in water
tube feet
The white parts are where the tube feet were in this sea urchin

7. (Sea Stars)
Mostly eat clams and oysters or other animal that is too slow to defend itself
It slowly pries open its prey in order to eat it, sending out its stomach to consume the body of the shellfish
They have two stomachs—one is used to eat and the other is used for digestion
Unlike the brittle star, sea stars’ organs enter their arms.
They can break off their arms and the arms can regenerate

8. (Sea Cucumber)
Sea cucumbers are scavengers, looking for food at the bottom of the ocean
They usually live in tropical reefs
If it is threatened, it will stiffen and a jet of water will shoot out of one end
If they feel threatened, they can also throw out their internal organs (evisceration) to distract predators, then grow new internal organs
Delicacy to eat in some countries
They use their tube feet to move very slowly

9. sea cucumber evisceration http://www. youtube. com/watch
Sea cucumber lifestyle

10. (Sea Urchin and Sand Dollars)
sand dollar moving
Sand dollars become bleached and loose their spines when left out in the sun on the beach, so the ones in the store are very different from live ones
Sea urchins have teeth made of calcium carbonate, and the entire chewing organ is called Aristotle's Lantern
Sea urchins mainly eat algae, but can also eat other invertebrates like mussels, sponges, and brittle stars
tube feet

11. Sea lilies were once thought to be planted in the ground but researchers found out that they actually can crawl from danger at 5 cm/s. They use their leg-like “petals” to crawl along the ocean floor. They use a lizard-like technique and leave their roots behind when escaping predators.
Feather Star Sea Lily

12. Brittle stars Long and nearly solid rays which move like snakes
Arms can regenerate
Carnivores, filter feeders, and scavengers
Coelem is smaller than other echinoderms