Echinoderms & Mollusks - Weebly

Echinoderms Mrs. Howards Life Science Echinoderms Sea stars (often referred incorrectly

as starfish) Sea cucumbers Sea urchins Brittle stars Live in a marine habitat Echinoderms - Body Description

Radially symmetrical Marine invertebrate Have a system of fluid filled tubes which aid in respiration, waste removal & movement (tube feet) Youtube Video on Echinoderm Body Plan https://www.youtube.com/watch? v=K2G7L5hcEt8

Echinoderm Protection Hard exoskeleton Spiny skin Some have poisonous stinging pincer-like organs

or use chemical secretions (asteroids) Some can entangle with white threadlike projections (sea cucumbers) Echinoderm Feeding

Some are carnivores that use tube feet to pry open the shells of bivalve mollusks Sea lilies, basket stars & brittle stars use tube feet on flexible arms to capture plankton that float by on ocean currents (filter feeding) Echinoderm Locomotion

Tube feet (similar to a hydraulic system) are used for locomotion There are also muscles within the spines that permit movement

Echinoderm Special Characteristics A sea cucumber will cast out its intestines to entangle, frighten or confuse a predator Sometimes, the predator will feed on these intestines allowing the cucumber to escape The sea cucumber then regenerates its intestines