Transcript echinoderms - Denton ISD

ECHINODERMS
Echinoderms are spinyskinned invertebrates that
live in the water.
Examples of Echinoderms
Sea-star/Star Fish
Sea urchin
Sand dollar
Sea cucumber
Echinoderms move around using
tube feet. They are hollow
structures with suckers on the
end. Water is pumped into the
tube feet and the feet extend.
Water is sucked back into the body
and feet contract. As the tube
feet extend and contract, the
echinoderm moves ahead.
STARFISH TUBE FEET
Let’s talk about
Sea-Stars
a.k.a. Star Fish
STAR FISH – they are also called
sea stars. They have five “arms”
and look somewhat like a pointed
star. Others have many arms and
are called “sun stars”.
STARFISH – CROWN OF
THORNS
PATRICK!!
Wouldn’t his camouflage
work better on the rock?!?
Starfish can regenerate new arms
when the old ones are broken off.
Even if a starfish is cut in two, each
of the pieces will regenerate into a
new animal. Most live for about three
to five years.
Close up of a starfish’s spines.
DOUGHBOY STARFISH
SUNFLOWER STARFISH
This starfish is hanging onto
the side with its tube feet.
BRITTLESTAR
What is a Sea
Urchin?
SEA URCHIN – the sea urchin is shaped
like a ball and is covered in long, moveable spines. They
are called scavengers because they feed on decaying
matter.
SEA URCHIN with other
invertebrates along for a ride!
Sea urchin spines and tube
feet.
Have you seen a
Sand Dollar
before?
SAND DOLLAR – The sand dollar lives slightly buried
in the sand. It eats tiny bits of animals and plants
found in the sand grains. The food travels along the
grooves on the underside of the sand dollar’s body to
its mouth.
SAND DOLLARS
The sand dollar has a thin, flat, circular body.
It looks like a silver dollar or a cookie. The
body of the sand dollar has many slots. The
top surface has a set of breathing tubes that
are arranged in the form of a five-point star.
The sand dollar’s body is covered with tiny
movable spines which are used for crawling and
digging.
http://www.youtube
.com/watch?v=cFF
CwQ1pIw&feature=relate
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Don’t forget about
Sea cucumbers!!!
Sea Cucumbers are unusual Echinoderms-their
supporting spines are microscopic and under their
skin. They are cylindrical in shape.
See the tube feet?!?
Sea
cucumbers
come in
many sizes
and colors.
One last sea cucumber!
A REALLY COOL FACT…
The starfish can push its stomach
out through its mouth!!!
Many starfish feed on shelled animals such as mussels,
clams, and oysters. When it feeds on an oyster, it attaches
its tube feet to the two halves of the oyster’s shell and
pulls the shell halves apart to make a tiny crack. Then the
starfish pushes its stomach into the crack. The stomach
surrounds the oyster’s soft body, slowly digests it, and
absorbs the food into its body.
Isn’t that amazing?!!!
THE END!
By: Julie Hunt and Marta Howard ~ Degan
Elementary