Download Echinodermata: Habitat and food source.

• Food source
– Carnivores eat clams
(starfish)
– Filter feeders filter
plankton (sea
cucumber)
• Marine environments
– Ranging from shallow
waters to the deep sea
• Environment
– Their skeletons
contribute to the
limestone formation;
helps with geographic
information.
• Humans
– Contribute to the
overall knowledge of
animal fertilization.
– Fossils also used to
decorate homes.
• Echinoderm means:
– “spiny skin”
• Been around since the Cambrian period.
• Regeneration
– Regrows an arm or body part
– Asexual reproduction
• Internal skeletons
– Made of Calcareous
plates known as
ossicles.
– Plates are crystals of
calcium carbonate
fused together.
• How they get oxygen
and release carbon
– Through the water
vascular system
– Bumps or spines on
surface take in oxygen
some of them have gill
structures.
• Gonochoristic- having
separate sexes.
• Male and female
discharge their eggs and
sperm into water and
that where the eggs are
fertilized.
• Develops into larva
• Settles in seabeds then
changes into a miniature
adults (metamorphosis)
• Click picture for more
details.
• Radial nerve cord
– Each radii are
equipped with radial
nerve cords.
– Connected by a nerve
that runs along the gut
( Esophageal nerve
ring).
– Controls muscles,
receives info such as
touch, chemicals, and
light.
• The water vascular
system and hemal
system derived from
coelom.
• (hemal-canal and
spaces.)
• Fluid moved by
muscular pumping.
• The waste is passes
through the mouth in
some echinoderms.
• Usually passes
through the water
vascular system.
• Diffuses across the
body surfaces to the
outside.
• Digestion occurs in the stomach and
digestive ceca.
• Tube feet
– Pick up sand and detritus then placed in
mouth.
– Mouth on the bottom.
•
•
•
•
•
Starfish
Brittle star
Sea cucumber
Sand dollar
Sea lillies
• Radial symmetry- can be divided in halves
at central point.
– Adults stage
• Bilateral symmetry- mirror like image.
– Larva stage.
• Features
– Contain sensory
neurons located at the
tube feet.
• Function
– Control of locomotion,
respiratory, and
feeding
Click to see video
• Echinoidea “sea urchins”
– Body plan: rigid endoskeleton with a covering
of outward-pointing spines.
– Spines include poisonous pedicellaria used
against predators.
– Echinoidea are herbivore or detritus feeders.
• Holothuroidea “sea cucumber”
– 900 species worldwide.
– Detritivores (eat decaying material)
– Usually green and bilateral symmetry and the
skin is leathery.
• Astroidea “starfish”
– 1700 living species.
– Movement involves hundred of tube feet.
– They feed by forcing their stomachs out of
their bodies to enter prey.
• Crinodea “feather star”
– Found in warm tropical seas.
– Attach to corals and other surfaces.
– Mouth and anus are both on top
– Movement involves flapping of the arms.
• Opsiuroidea “Brittle star”
– Ophiuroid means “snake-like”.
– Moves by using the arms in a rowing stroke.
– They are detritus feeders.
• "Animals: Aquatic; Echinoderms; Sea Lilies, Star Fishes, Urchins,
Sea Cucumbers." Echinoderm. 6 Apr. 2008
<http://www.photovault.com/Link/Animals/Aquatic/oEchinoderms/AA
OVolume01.html>.
• "Echinodermata." Animal Diversity Web. 2008. University of
Michigan Museum of Zoology. 30 Mar. 2008
<http://animaldiversity.ummz.umich.edu/site/index.html>.
• "Echinodermata." Larousse Encyclopedia. New York: Larousse &
Co. Inc., 1969.
• http://www.virted.org/Animals/Starfish.html (didn’t give any more
information)
• Miller, and Levine. Biology: the Living Science. Upper Saddle River:
Prentice-Hall, Inc., 1998. 657-659.
• Wray, Gregory A. "Echinodermata." The Tree of Life Web Project.
Dec. 1999. 30 Mar. 2008 <http://www.tolweb.org/echinodermata>.
• World of Animals: Insects and Others. Danbury: Scholastic Library,
2004. 89.