echino = “spiny” dermis = “skin”

Echino = “spiny”Dermis = “skin”

Some different echinoderms

Unifying CharacteristicsSpiny SkinInternal Skeleton – “endoskeleton”

Water vascular system

Muscular tube feet (suction cup feet)

Pentaradia Symmetry5 rays of symmetry

Water Vascular System

Madreporite - sieve-like opening to the water vascular system

Water Vascular SystemFunctions:

RespirationRing & Radial CanalsTube Feet

CirculationRing & Radial Canals

MovementTube Feet

Tube FeetEach tube foot is basically a suction cup, muscles pull up the centre of the cup causing suction

Many feet working together can exert huge force, allowing “walking” and attacking

Groups of EchinodermsSea Urchins and Sand Dollars

Grazers and DetrivoresSolid plates protect internal organs

Brittle StarsFilter feeders and DetrivoresSlender/Flexible arms – detach and distract

Sea CucumbersDetrivoresEviscerate themselves as defence!

Sea StarsPredatoryRegenerative if dismembered!

Sea Lilies and Feather StarsFilter FeedersFeather dusters of the sea

Sea Urchins and Sand DollarsGrazers and DetrivoresSolid plates protect internal organs

Brittle StarsFilter feeders and DetrivoresSlender/Flexible arms – detach and distract

Sea CucumbersDetrivoresEviscerate themselves as defence!

Sea StarsPredatoryRegenerate if dismembered!

Sea Lilies and Feather StarsFilter FeedersFeather dusters of the sea