Echinoderms

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Echinoderms
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Echinoderms

• Echinoderm means spiny skinned
• 5 Classes
• Sea Stars
• Brittle Basket Stars
• Sea Urchins Sand Dollars
• Sea Lilies Feather Stars
• Sea Cucumbers
• All are marine (ocean)
• Bottoms of oceans all over the world
• Eat mollusks, dead organisms, algae

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More about Echinoderms

• Endoskeleton internal skeleton
• Spines on outside of endoskeleton can be long
  sharp or short bumpy
• Radial symmetry
• Larva have bilateral symmetry

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Water Vascular System

• Unique to echinoderms
• WVS is a system of canals filled with water
• Water pressure from the WVS is used to help the
  sea star move, eat, breathe, and sense its
  environment
• Tube feet tiny suckers on the bottom of a sea
  star used to move and capture food

Radial canal
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Brittle Stars Basket Stars

• Long, slim arms
• Usually smaller than sea stars
• No suckers on tube feet

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Sea Urchins Sand Dollars

• Round
• No arms
• Tube feet to move
• Some walk on their spines
• Sea urchins eat algae
• Sand dollars burrow into sand and eat tiny
  particles

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Sea Lilies Feather Stars

• 5 200 feathery arms
• Trap small pieces of food in their arms

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Sea Cucumbers

• No arms
• Soft
• Leathery
• Long
• Worm-like shape

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The End