Echinoderms
Review
Starfish belong in the
Animalia
KINGDOM _______________
Echinodermata
PHYLUM _______________
CLASS ___________________
Asteroidea
invertebrates
Echinoderms are _________________
vertebrates
invertebrates
radial
Adult echinoderms have ______________
symmetry.
no
bilateral
radial
Deuterostomes
_____________ are organisms
whose anus develops from the
blastopore area in the embryo.
Cardiac
The ______________
stomach in a
starfish is extruded out through the
mouth to eat.
Since a starfish has NO INTESTINE,
the nutrients are absorbed by the
digestive glands
_______________
Portion of the stomach that is
connected to the anus and
digestive glandsPyloric stomach
Echinoderms have an endoskeleton
made of calcium carbonate plates
ossicles
called _______________.
In Latin the name “echinoderm” means
__________________
Spiny skin
Name one of the 3 characteristics
your book lists that are found only
in echinoderms.
Endoskeleton made of OSSICLES
Water vascular system
Tube feet
Sea stars (starfish) belong to the
Class _________________
Asteroidea
The mouth of a starfish is located
on the _____________
surface.
oral
All of these organisms belong to
Echinodermata
the phylum _______________
(Echinoderms)
The small tiny pinchers at the base of
the spines on the surface of a starfish
pedicillariae
are called _______________
Water enters the water vascular
system through small pores in the
madreporite
__________________.
open
Starfish have _____________circulation.
The small movable suction cupped
extensions of the water vascular
system which aid in locomotion and
feeding are called _____________.
tube feet
What is the function of the
ampullae?
Squeeze to control water entering
and leaving the tube feet
The seastar can turn its ___________
cardiac
stomach inside out through its mouth
when it eats.
Compare Digestive and Nitrogen waste
DIGESTIVE
WASTE
NITROGEN
WASTE
Made where?
In digestive tract
By body cells
Comes from?
Left over from
undigested food
Removed by
what body system?
Leaves body as?
Digestive
Feces
breakdown of proteins
during metabolism
Excretory
ammonia, urea,
OR uric acid
The stone canal, ring canal, and radial
canal are all parts of the
water vascular system.
________________
Nutrients are absorbed in the
digestive glands
________________in
a starfish.
Tell a function of the tube feet.
Locomotion
Hold onto & pry open clam shells
Gas exchange/remove nitrogen waste
The skin gills on the surface connect
coelom
into the ___________inside.
The network of water filled canals
connected to the tube feet is called
the _________________
Water vascular system.
carnivores
Most starfish are _______________.
Carnivores
herbivores
omnivores
This organ absorbs nutrients in an
earthworm and a clam but is missing in
starfish
intestine
Echinoderms are thought to be more
closely related to higher organisms like
vertebrates because _______________
their blastopore becomes the anus just like
in higher organisms
The bulb-like sac at the upper
end of each tube foot is called
the _____________
ampulla
The spines on the surface connect
into the ____________ inside.
Ossicles of the endoskeleton
Type of reproduction seen in starfish
Asexual
Sexual
They can do both!
Symmetry seen in echinoderm larvae
bilateral
T or F
Most echinoderms are hermaphrodites.
False, they have separate sexes.
Fertilization in echinoderms is
_______________
external
External
internal
Seastars “breathe” by exchanging
gases through their
_____________________________.
skin
gills and skin on their tube feet
Echinoderms are missing all of these
organs except ____________.
digestive
Circulatory excretory respiratory
digestive
Name one of the parts of the nervous
system in a starfish.
Nerve ring or radial nerve
The ability of starfish to regrow
lost arms is called regeneration
________________.
Type of symmetry seen in echinoderm
larva
bilateral
General term for reproductive organs
gonads
The tube that connects the
madreporite to the ring canal is
stone canal
the ____________________
The surface of a starfish opposite
aboral
from the mouth is the _____________
Surface.
The digestive glands connect to the
pyloric
__________________
stomach.
cardiac
The ___________________
stomach is
extruded out of the mouth during
feeding
What is the function of the
pedicillariae?
Keep surface of starfish free of
algae and small organisms that might
damage or block it
eyespots
Starfish have _____________
at the
ends of each arm that can sense
light and dark
The anus and madreporite are on the
____________
surface of a starfish.
aboral
deuterostomes
Echinoderms are _______________
Protostomes
Deuterostomes
Starfish absorb oxygen through their
Skin gills
_______________
and the surface of
their _________________
Tube feet
Name a part of the nervous
system in a starfish
Nerve ring, radial nerves, nerve net, eyespots
Organisms in which the
blastopore becomes the
anus are called
deuterostomes
__________________
Special kind of
radial symmetry
seen is 5 armed
starfish pentaradial
Body part used in respiration in a starfish
Skin gills
Which of the following is true about the
circulatory system in a starfish?
Aortic arches surround the digestive system & pump blood
A heart surrounded by a pericardial cavity pumps
hemolymph
No heart or blood vessels. Fluid in the coelom bathes and
distributes nutrients & oxygen
No heart or blood vessels. Fluid circulates in the coelom
Name a part of the digestive system
in a starfish
Mouth, pyloric stomach, cardiac stomach,
digestive glands, anus
All echinoderms are MARINE.
live in oceans
That means they ____________.
have military-like camouflage
live in the ocean
march in lines like soldiers
stay in one place
Tell the body system each part
belongs to:
vascular
Madreporite Water
_____________________
nervous
Nerve ring
_____________________
Water vascular
Ring canal
______________________
Ossicles
______________________
Skeletal
Reproductive
Gonads
______________________
Respiratory/excretory
Skin gills
______________________
Digestive
Cardiac stomach ___________________
Main body part used in respiration
in a starfishSkin gills
Spines on the surface connect
to the ________________
underneath.
ossicles
Trace the path that water follows in the
water vascular system:
Madreporite
Stone canal
_____________________
Ring canal
_____________________
Radial canal (or abulacral
_____________________
tube feet
canal)
The digestive glands connect to the
pyloric
__________________
stomach.
Type of symmetry
seen in this
echinoderm
radial
Name a body system that is missing in
starfish Excretory
Respiratory
Circulatory
eucoelomates
Echinoderms are _________________
acoelomates
Pseudocoelomates
eucoelomates
Name 6 characteristics of Echinoderms
Eucoelomates
Invertebrates
Deuterostomes
Spiny skin
Water vascular system with tube feet
Endoskeleton made of ossicles
Radial symmetry
Bipinnaria larva
marine
What are the odds you will see a question
like this on the test? I’d say pretty good!
trochophore
bipinnaria
This one!
Type of larva found in echinoderms
Tube feet are found along the
__________________
groove.
ambulacral
When you cut into the starfish, the
space you see around the internal
coelom
organs is the ______________
Mantle
cavity
pseudocoelom
coelom
pericardial
cavity
The ventral surface is also called the
oral surface.
_______
TRUE or FALSE
Starfish are hermaphrodites
False. They have separate sexes
This diagram represents the 3 structures you
learned about on the surface of a starfish.
spines
The blue structures are _____________
protection
for _____________________.
The red structures are ____________
Skin gills
for Exchanging
____________________
gases/removing nitrogen waste
The green structure is a _____________
pedicellaria
for _________________________
keeping the surface free of organisms
Tell the function of each part:
Opening for water
vascular system
_____________________
madreporite
Absorb nutrients
_____________________
Digestive glands
Connect madreporite
Stone canal
to ring canal
______________________
Plates that fuse to form
ossicles
skeleton
______________________
Make sperm or eggs _________________
gonads
Exchange gases and get
rid of nitrogen waste
_________________
Skin gills
Tell the function of each part:
Keep skin free of
organisms
_____________________
pedicellariae
Extruded out through
stomach
mouth during feeding Cardiac
________________
Stomach that connects
to digestive glands ______________________
Pyloric stomach
Squeeze to move water
up and down in tube feet _________________
ampullae
spines
Spikes on surface for protection _____________
A
B
E
C
D
MADREPORITE
A = _________________
STONE CANAL
B = _________________
RING CANAL
C = _________________
RADIAL CANAL
D = _________________
F
AMPULLAE
E = ___________________
TUBE FEET
F = ___________________
What do the typhlosole in an earthworm, the
ridges on the gills in a clam, and the skin
gills of a starfish have in common?
All are structures used to
INCREASE SURFACE AREA
Asteroidea comes from the Latin
star
word meaning _______________
The only invertebrates that are
NOT PROTOSTOMES are the
_________________________
echinoderms
What is the plural of pedicellaria?
pedicellariae
All echinoderms are MARINE. This
means they Live
_______________
in salt water (oceans)
How is reproduction in a starfish
different from that of an earthworm?
Earthworms= hermaphrodites
Starfish= separate sexes; can use
regeneration for asexual reproduction
Explain how diffusion is important to starfish
Diffusion of gas molecules from
high concentration to low concentration
is what causes gas exchange for breathing
Which of the following is an echinoderm
larva?
A
B: Echinoderms have a:
B
BIPINNARIA larva with wings
Tell one way the starfish are similar to
clams.
Both have: NO CEPHALIZATION
Open circulation (NO blood vessels)
eucoelomates
invertebrates
separate sexes
sexual reproduction
with external fertilization (marine clams)
indirect development (start as larva)
have digestive gland that makes bile and
absorbs nutrients
have stomach attached to digestive gland
Tell one way the starfish are DIFFERENT
FROM clams.
Clams:
Protostomes
Have an intestine
Heart pumps hemolymph
Gills exchange gases
Kidney to remove nitrogen
Starfish:
Deuterostomes
No intestine
No heart
Gases exchanged thru skin gills
no excretory organs/
nitrogen waste out thru skin gills
------water vascular system
Shell for protection
endoskeleton/spines for protection
Filter feeders
carnivores
some have internal fertilization external fertilization
(freshwater clams)
Sexual reproduction only
Can do sexual/asexual reprod.
Tell one way the starfish are similar to
earthworms.
Both have: true coelomates
invertebrates
sexual reproduction
external fertilization
Tell one way the starfish are DIFFERENT
FROM earthworms.
Earthworms:
Starfish:
Protostomes
Deuterostomes
Intestine to absorb nutrients
digestive glands absorb nutrients
Heart (aortic arches) pumps blood No heart
Nephridia to remove nitrogen
no excretory organs/
nitrogen waste out thru skin gills
------water vascular system
Hydrostatic skeleton
endoskeleton/spines for protection
Closed circulation
Open circulation
Direct development
Indirect development
Cerebral ganglia/nerve cord
Nerve ring, radial nerves, ganglia
Why are echinoderms thought to have
evolved from a bilaterally symmetrical
ancestor?
They have a bilaterally symmetrical larva
Which 2 structures you learned about
are contained within the ambulacral
ridge?
Radial nerve & radial canal
Name another echinoderm besides a
starfish.
Sea lily, feather star, brittle star, sea urchin,
Basket star, sand dollar, sea cucumber
indirect
Starfish have __________development.
They start out as a larva that looks different from the adult.
direct
indirect
Name one of the structures found on the
surface of a starfish and tell its function.
Spines- protection
Pedicellaria-pinchers that keep surface
clear of organisms
Skin gills- exchange gases/remove nitrogen waste
True OR False
Sea stars can reproduce both sexually
and asexually.
TRUE
They have separate sexes and can use regeneration.
A sea star’s nervous system does NOT include
______________
a brain
Nerve ring
nerve net
radial nerves
cerebral ganglia
Explain how a mollusk trochophore
larva is different from an echinoderm
bipinnaria larva.
Trochophore larvae are egg shaped with a ring of
cilia to help them swim;
Bipinnaria have wings