phylum echinoderms

what does Echinodermata mean?

spiny skin

what type of symmetry do Echinodermata have?

radial symmetry

what are some examples of Echinodermata?

Sea Star, Sea Urchin, Sea Cucumber, and sand dollars

what is their internal skeleton made of?

they are made of stiff plates of calcium called ossicles

what is the Bipinnaria?

the larvae of echinoderms

what is a water vascular system?

Network of fluid-filled canals that transport water throughout the echinoderms body creating a powerful suction for movement, opening up mollusk and gripping surfaces

an echinoderms water vascular system is connected to the…

tube feet

what are tube feet used for?

feeding, movement, respiration, excretion

what is a Madreporite?

small pores on the dorsal surface where water enters. It is attached to the stone canal, which is attached to the ring canal

what is the stone canal?

short tube attached the madreporite to the ring canal

what is the ring canal?

ring in the center of the sea stars body that attaches to the radial canals

what is the radial canal?

extends from the ring canal to the end of each arm which carries water to hundreds of tube feet

what are tube feet?

end of the radial canal. Much like a suction cup that has a sucker on the end and muscles, With water, suckers, and muscles, a hydraulic system is created, creating an enormous force for walking and opening clams

what is the ampulla?

a bulblike sac found on each end of a tube foot where water is forced in and out

how do Echinoderms feed?

they have an oral side where their mouth is located where it pulls its food into

what are Echinoderm’s nervous system comprised

nerve cells, radial nerves, sensory cells, eyespots, and

statocysts

Echinoderms have no brain, instead they have…

nerve cells which are called a nerve ring with connecting nerves called radial nerves

what are the classes of Echinoderms?

Asteroidea, Ophiuroidea, Echinoidea, Holothuriodea,

Crinoidea

describe the Asteroidea class

they have five or more arms with tube feet and are carnivores

what is another name for the Asteroidea class?

starfish or sea starts

sea stars have the ability to…

regenerate an arm as long as part of the central cavity is present

describe the class Ophiuroidea

they are nocturnal and have long thin, flexible arms

what are some examples of

Ophiuroidea?

brittle stars and basket stars

examples of Echinoidea

sand dollars and sea urchins

what type of feeders are Holothuriodea?

detritus feeders

what is an example of the

Holothuriodea?

a sea cucumber

Crinoidea are the…

most ancient of the Echinoderms