ECHINODERMATA

DEFINITION

• Characterized by...
• Internal skeleton.
• A water vascular system.
• Suction cup-like structures called tubefeet.
• Spiny skin

EXAMPLES

• Sea Stars
• Sea Urchins
• Sea Cucumbers
• Sand Dollars
• Sea Lilies

BODY ORGANIZATION

• Echinoderms have a water vascular system consisting of a network of radial canals, which extend through each of the five extensions (arms or rays) of the animal.
• At the ends of each appendage are usually suckers known as tube feet.
• Echinoderms have large coeloms.
• Echinoderms have endoderms.

SYMMETRY

• Most Echinoderms posses radial symmetry as adults.

SIZE

• Echinoderms range from 10cm to 2m.

ADAPTIONS

• To ward off predators, Echinoderms may have spines or toxins.

DIGESTION

• Sea urchins use five part jawline structures to scrape algae from rocks.
• Sea lilies use tube feet along their arms to capture floating plankton.
• Sea cucumbers move like bulldozers across the ocean floor to take in sand and detritus.
• A Sea star may push its stomach through its mouth and pour enzymes out into an open clam or mussel.
• This would digest the prey and the sea star then consumes its stomach and digested prey into its mouth.

HABITAT

• Being mostly a marine group, Echinoderms are found in all oceans.

CHARACTERISTICS

• Water vascular system
• No heart
• No eyes
• No brain

FUN FACT

• Should a sea cucumber be placed in fresh water, it will explode.

FUN FACT

• Echinoderms do not have blood!

FUN FACT

• Sea Urchins are considered delacaciess in many countries.

FUN FACT

• Appropriately, Echinodermata means Spiny Skinned in Greek.

FUN FACT

• Many Echinoderms have the ability to regenerate lost limbs.

CIRCULATION

• Sea water flows through canals in the Echinoderm's appendages.
• Echinoderms have an open circulatory system with fluid flowing through each appendage.

RESPIRATION

• Oxygen from the sea water passes through the body by the fluid in the main body cavity.

EXCRETION

• Digestive wastes are ejected through the anus, the main excretory structure, as feces.
• Nitrous-containing cellular wastes are usually in the form of Ammonia.
• This waste is passed into the water through tube feet and skin gills.

REPRODUCTION

• The majority of Echinoderms reproduce sexually through external fertilization.
• Parental care may vary from immediate abandonment to brooding.

INTEGUMENT

• Echinoderms are covered in rough or spiny skin.
• This is a defense against predators.

WORKS CITED

• Mulcrone, R. 2005. "Echinodermata" (On-line), Animal Diversity Web. Accessed April 14, 2014 at http://animaldiversity.ummz.umich.edu/accounts/Echinodermata/