1. Mrs. Howard’s Life Science
Echinoderms
Mrs. Howard’s Life Science

2. Echinoderms Sea stars (often referred incorrectly as starfish)
Sea cucumbers
Sea urchins
Brittle stars
Live in a marine habitat

3. Echinoderms - Body Description
Radially symmetrical
Marine invertebrate
Have a system of fluid filled tubes which aid in respiration, waste removal & movement (tube feet)

4. Youtube Video on Echinoderm Body Plan

5. 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)

6. 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)

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

8. 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