What is the phylum and who are members of the echinoderms?
Where are they found?
phylum Echinodermata, include starfish, sea urchins, feather stars, sea cucumbers
marine only
What are the 3 main body characteristics of echinoderms?
deutorostomes, no cephalization and nerve net
Echinoderm larval form is…
free swimming and bilaterally symmetrical
How does the echinoderm digest food?
digestive glands
within arms or on outer body wall
short system
How does the echinoderm reproduce?
- asexual and sexual
- external fertilization produce larvae
carnivorous or herbivorous
sex organs in arms
How does the echinoderm’s respiration system work?
not true system, skin gills for gas exchange
How does the echinoderm’s muscular system work?
- water vascular system
- tube feet
- ampulla that pumps water into tubes, increasing pressure in tube foot and causing it to expand
What class are sea stars in and what type of symmetry do they have?
class Asteroidia, radial symmetry
How does the sea star digest food?
food entering the cardiac then pyloric stomach
carnivorous and predators of mollusks
How does the sea star reproduce?
- sexual + dioecious
- external fertilization
free swimming larvae bipinnaria produced
ability to regenerate is asexual
What is the sea star’s muscular system?
- water vascular system
- tube feet - produce suction for movement
What is the sea star’s nervous system?
central radial nerve ring
nerve nets connect them to each arm
What is the sea star’s skeletal system?
- internal
- ossicles - bony plates
What are the sea star’s circulatory, excretory, and respiratory systems?
NONE
Where is mouth and anus located on a sea star?
mouth located on underside, anus directly opposite mouth
What are the two unique sea star features?
- madreporite - water intake on top
- pedicellaria - ensure surface of arms stay free
