1. Chapter 29 Section 1 Echinoderms
Essential Question:
Explain the similarities and differences among the classes of echinoderms and how are they related to chordates?
Objectives:
To compare similarities and differences among the classes of echinoderms.
To interpret the evidence biologists have for determining that echinoderms are close relatives of chordates.

2. New Vocabulary:
Ray: Starfish- long tapering arm covered with short, rounded spines.
Pedicellaria: pincerlike appendages- used for protection and cleaning the surface of its body.
Water vascular system: hydraulic system that operates under waterr pressure. Water enters and leaves the water vascular system through the (4)madreporite, a disk-shape opening on the surface of the echinoderm’s body.
Tube Foot: hollow, thin-walled tubes that end in a suction cup.
Ampulla: related to the tube feet, they look like miniature droppers and the ampulla works like the bulb of a dropper.

3. What is an Echinoderm? Characteristics that are unusual
Hard, spiny or bumpy endoskeletons
Starfish have short, rounded spines
Sea urchins, long pointed spines
Endoskeletons made of calcium carbonate, compound that makes up limestone
Have pedicellaria that are modified spines
Pincerlike appendages that help protect and clean

4. Characteristics Radial symmetry Water vascular systems:
move, exchange gases, capture food, and excrete wastes
Water is pumped in and out of the echinoderm through the madreporite that acts like a sink drainer only letting small particles in.
Have tube-like feet on the underside of each ray
Not only for movement but also function in gas exchange and excretion- thin walled

5. Characteristics Nutrition:
Worms, mollusks, algae, dead and decaying matter depending on the species
Central nerve ring that surrounds the mouth, no head or brain
Eyespot found on each tip of the arms that allows for light detection

6. Characteristics Bilaterally symmetrical larvae
Echinoderms are deuterostomes:
Shows the close relationship to chordates
Diversity of Echinoderms
There are 6000 species

7. Sea Stars or Starfish

8. Brittle Stars

9. Sea Urchins

10. Sand Dollars

11. Sea Cucumbers

12. Sea Lilies

13. Feather Stars

14. Sea Daisies

15. Early Echinoderms

16. Questions for Review:
How does a sea star move? Explain in terms of the water vascular system of echinoderms.
What evidence suggests that echinoderms are closely related to chordates?
How do the various defense mechanisms among the echinoderm classes help deter predators?

17. Videos to compliment the notes:
You Tube:
BBC Plannet Earth Episode 9 Shallow Seas Full Documentary Film BBC Documentary