Phylum Echinodermata Flashcards
1
Q
What are the classes in phylum Echinodermata?
A
- class Asteroidea - sea stars
- calss Ophiuroidea - brittle stars
- class Echinoidea - sand dollars
- class Holothuroidea - sea cucumbers
- class Crinoidea - feather stars
2
Q
The general characteristics of echinoderms:
A
- deuterostome
- eucoelomate
- radial pentamerous symmetry in adults
- bilateral symmetry in larva
- NO cephalization
- locomotion by tube feet
- seperate sexes
- NO excretory organs
3
Q
Characteristics of Class Asteroidea:
A
- complete gut
- five or more arms
- endoskeleton of ossicles connected by tissue
- pedicellariae = help remove debris and used as defense
- madreporite = entry to water vascular system
4
Q
Characteristics of Class Ophiuroidea:
A
- 5 arms
- NO pedicellariae or papula
- madreporite on oral surface
- NO anus or intestine
- five pairs of bursae (between arms)
5
Q
Characteristics of Class Echinoidea:
A
- ossicles fused to form test (shell)
- anus and madreporite on aboral surface
- pedicellariae present
- 5 pairs of ambulacral grooves with tube feet
6
Q
Characteristics of Class Holothuroidea:
A
- ambulacral region well developed on one side
- respiratory tree for better oxygen circulation
- can do evisceration for protection and recycling of toxins in body
7
Q
Characteristics of Class Crinoidea:
A
- 5 arms branched at base and bearing pinnules
- NO madreporite, spines or pedicellariae
- tube feet in ambulacral groove
- upper surface is oral, where anus and mouth are found
