Phylum Echinodermata Flashcards
Cleavage is spiral and determinate
Protosome
Cleavage is radial and indeterminate
Deuterostomes
Blastopore becomes mouth
Protosome
Blastopore becomes the anus
Deuterostomes
Coelom forms by a splitting of the mesoderm
Protosome
Coelom forms by an outpocketing of primitive gut
Deuterostomes
_____ include sea stars, brittle stars, sea urchins, sand dollars, sea cucumbers, and sea lilies.
Echinodermata
Internal skeleton of calcareous plates in echinoderms is called
Ossicles
Adult echinoderms are radially symmetrical and their bodies consist of 5 repetitive parts meaning they are _____.
Pentaradial
Larvae of echinoderms are _____ symmetrical.
Bilaterally
What are the classes of phylum Echinodermata?
Asteroidea Ophiuroidea Crinoidea Echinoidea Holothuroidea
What is the genus of class Asteroidea?
Asterias
The _____ is on the lower, oral surface.
Mouth
The ____ is on the upper, aboral surface.
Anus
What is used for respiration by diffusion in Asteroidea?
Dermal Gills
What is used to remove debris from the surface of Asteroidea?
Pedicellariae
What are tube feet used for in echinoderms?
For locomotion and to grip and pull apart prey such as clams.
On the aboral surface is the _____, a sieve connecting the water vascular system with the environment.
Madreporite
What is the consistency of the madreporite?
Smooth
What part of the water vascular system extends into each arm?
Tube foot
What other phylum besides echinodermata depend on “hydraulics” as part of their locomotion system?
Annelida and Cnidarian
What allows brittle stars to crawl rapidly like octopus rather than creep slowly like sea stars?
Thin, flexible arms
What are the most ancient echinoderms?
Class Crinoidea (sea lillies and feather stars)
What does class ophiuroidea consist of?
Brittle stars
Why do class crinoidea differ from other living echinoderms?
Their oral surface (mouth and anus) usually face up
Crinoids filter feed by capturing food particles on the ____ of their tube feet.
Mucus
What does class echinoidea consist of?
Sea Urchins and Sand Dollars
What is the genus of class echinoidea?
Arbacia
Urchins lack distinct arms and their ossicles are fused into a solid shell called a
Test
The mouth in class Echinoidea contains five ossified plates, or teeth used to scavenge and scrape surfaces of rocks and gather algae for food. This is called
Aristotle’s lantern
Class Holothuroidea consists of
Sea cucumbers
Some sea cucumbers respond to stress by rupturing anteriorly and rapidly expelling their pharynx, digestive tract, and other organs. This is called
Evisceration
