Phylum Echinodermata

Echinodermata

All echinoderms are marine organisms

7,000+ species

Ex: starfish, sea urchins, sea cucumbers

and sand dollars.

Starfish

Sea urchins

Sea cucumbers

Sand dollars

Characteristics

Most exhibit pentamerous radial symmetry (can be divided into 5 equal parts from a central axis)

During development, they go through bipinnaria larva stage (bilateral symmetry – suggests evolution from a bilateral symmetrical ancestor)

Have tube feet with suction disks used in locomotion and getting food.

Characteristics cont…

Has an endoskeleton to protect it’s soft

tissues and is where muscles attach

Spiny projections (Echinoderm means

“spiny skin”)

Major unifying characteristic is their water

vascular system. Interconnecting, fluid

filled tubes that act like a hydraulic

pressure system

Recap of Animal Kingdom Phyla

Invertebrates – no backbone!

Phylum #1

1. Porifera

Representative Species?

SPONGE

Phylum #2

2. Cnidaria

Representative Species?

Jellyfish, hydra

Phylum #3

3. Platyhelminthes

Representative Species?

Flatworms (turbellarians, flukes, tapeworms)

Phylum #4

4. Nematoda

Representative Species?

Roundworms (ex: hookworm)

Phylum #5

5. Annelida

Representative Species?

Earthworm

Phylum #6

6. Mollusca

Representative Species?

Snail, clam, squid

Phylum #7

7. Arthropoda

Representative Species?

Crayfish, spiders, centipedes

Phylum #8

8. Echinodermata

Representative Species?

Starfish, sea cucumbers, sea urchins

Animal Kingdom: Phylum #9

Vertebrates (with a backbone)

Phylum Chordata

Finally…..

United streaming Video Clip –

Echinoderms (5 minutes)

Video Quiz