Or-Lets learn more about our Spiny Skinned Friends!

Spiny internal skeleton-endoskeleton

Radial symmetry Body parts in

multiples of 5

Water vascular systemFluid filled tubes that fill an echinoderm’s body. Parts of the tubes can contract, squeezing water into tube feet. Tube feet are sticky on the end and when filled with water, they are like suction cups. The tube feet allow the echinoderm to hold onto the surface under them or another animal.

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Echinoderms can reproduce sexually-male and female echinoderms release egg and sperm into the water. The fertilized eggs become tiny, swimming larvae and eventually become adult echinoderms.

Echinoderms can also reproduce asexually-some species of sea stars can grow a whole new animal from an arm!

Many echinoderms can regenerate-grow new body parts when one is lost.

Brittle stars (cousins to sea stars) have long flexible arms that they use to move. They don’t have tube feet, to move they push themselves along the ground.

Sea cucumbers have tentacles around their mouth like a sea anemone. But unlike sea anemones, they are not sessile. Sea cucumbers have tube feet that allow them to move slowly along the ocean floor.