phylum echinodermata (means spiny skin)

Phylum Echinodermata (Means spiny skin)

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Phylum Echinodermata (Means spiny skin). Echinodermata. Classes. Asteriodea(Stelleroids). Sea stars. Aka starfish. Echinodermata. Classes. Crinoidea/Crinoids. Feather stars. Sea lilies. Echinodermata. Classes. Echinoidea/Echinoids. Sea urchins, sand dollars. - PowerPoint PPT Presentation


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Phylum Echinodermata(Means spiny skin)

1EchinodermataClassesSea starsAsteriodea(Stelleroids)Aka starfish


Feather stars

Sea lilies3EchinodermataClassesCompact body within a shellEchinoidea/EchinoidsSea urchins, sand dollars

No arms, often spiny4EchinodermataClassesElongated bodyHolothuroidea(Holothuriods)Sea cucumbers

Leathery body wall with embedded ossicles(bony plates)5OphiunoideaBrittle stars, Basket stars

(Add this to your hand out!)EchinodermataCommon Characteristicsas opposed to bilateralRadial SymmetryLike spokes on a wheel

7EchinodermataCommon CharacteristicsOr CylindricalBody may be roundWith 5 or more ambulacra (radiating areas)

Or star shaped

8EchinodermataCommon CharacteristicsCan regenerate lost partsEndoskeletonwith spines or spicules

9EchinodermataCommon CharacteristicsSimple Nervous systemNo head or brainNo excretory organsFew specialized sensory organs

Nerve ring / radial nerves

10EchinodermataCommon CharacteristicsWater Vascular SystemWater is taken in at the madreporite

Helps with respiration,Circulation and movement11

Specialized structuresMouth and anus ingestion and excretion of digestive wastesMadreporite sieve like structure through which water istaken in. Some species - gills

Tube feet for movementGonads - make gametes (sperm and eggs)13EchinodermataAnatomy

14EchinodermataReproductionOr gonochoric(two distinct sexes)May be hermaphrodites

Usually release sperm / egg into the water columnExternal fertilizationMany species synchronize this, along the lunar cycle

15EchinodermataNutritionThey have specialized mouthparts for thisMost sea urchins scrape algae off surfaces

Called Aristotles lantern

A few are scavengers or predators16EchinodermataNutritionSome are active filter feedersBrittle stars are mostly scavengers

Or just lay about waiting for food to float by and stick to them

They crawl about on the bottom looking for dead stuff

17EchinodermataNutritionThey tear open mollusks with their armsSea stars are carnivores

Then extrude their own stomach out of their mouths to release digestive juices into the clams body.18They eat mollusks like clams and mussels, some eat coral (Crown of thorns)

Answer to #6 on the hand out