Upgrade to remove ads
Terms in this set (23)
Echinoderm (Literal Meaning)
Sea stars, brittle stars, sea urchins, sea cucumbers
Echinoderm Basic Characteristics
Marine invertebrates with spiny skin and radial symmetry and tremendous powers of regeneration
Why are Echinoderms thought to be closely related to Chordates?
They are deutertomes - as are chordates
animals with a mouth that develops from cells other than those of the opening of the gastrula (mostly chordates)
Hard plates that are bumpy or spiny
Composed of mostly calcium carbonate
Connected by bands of soft tissue and muscle
Covered with a thin epidermis
Different types of "Spines"
Sea stars - short and rounded
Sea urchins - long and sharp
Sea cucumbers - small and plate like
Sand Dollar - fused into rigid plates
spines modified into pincer like appendages
used for protection and cleaning.
Opening through which water flows
internal bulbs at base of feet to cause "suction"
Used in movement, feeding, respiration and excretion
Echinoderm Feeding Patterns
Sea stars are carnivorous
Most sea urchins are herbivores
Brittle stars, sea lilies, and sea cucumbers feed on dead and decaying matter.
Water Vascular System
water flows in and out through the madreporites
used for gas and waste exchange
Echinoderm nervous system
simple nervous system
Echinoderms have no head or brain
a central nerve ring surrounds the mouth
Nerves extend from the nerve ring down each ray.
Echinoderms have amazing powers of regeneration
Many species routinely automize and regenerate arms or organs ex: sea stars , sea cucumbers
Most species have separate sexes with external fertilization
Few species are hermaphroditic
Support and Defense
internal skeleton and spiny skin
some can automize and regenerate arms and organs
some species the lost part can grow into a new individual
Importance of Echinoderms
Important part of many ecosystems including shallow oceans to deep seas
Their endoskeletons are major contributors to many limestone formation
Most abundant deuterosome invertebrate
Sea urchins, sand dollars
Sea lilies and feather stars
Origin of Echinoderms
1. Left behind an extensive fossil record
2. Inconclusive evidence of late Precambrian
3. First conclusive appearance in the lower Cambrian
4. Asteroidean fossils appear in the Ordovician
5. Crinoid fossils dominate the Paleozoic
THIS SET IS OFTEN IN FOLDERS WITH...
Chapter 16: Invertebrates II: Mollusks, Echinoderm…
Animals BIO 201
YOU MIGHT ALSO LIKE...
Marine Bio Invertebrates & plants
BIOL 111 Lecture 16
OTHER SETS BY THIS CREATOR
Chemistry B - EOC Test Review
Chemistry A Brief Overview
Chemistry A EOC Exam Prep Set
Matter and Change