Invertebrates - Echinodermata

Question 1

what are the traits of echidnoderms?

Answer 1

-spiny skinned marine organisms
-includes sea stars, sand dollars, sea cucumbers
-exclusively marine
-larvae is bilateral, adults are radially symmetrical

Question 2

why is this phylum grouped with chordata?

Answer 2

-both are coelomate and deuterostomes

Question 3

what type of skeleton do echidnoderms have and what system do they have?

Answer 3

-endoskeleton made of calcareous plates
-have a water vascular system which works in locomotion, feeding, and gas exchange

Question 4

what are the traits of the class ophiuroidea? what animal is this?

Answer 4

-brittle stars
-have a central disk and long flexible arms

Question 5

what are the traits of the class echidnoidea? what animals are these?

Answer 5

-sea urchins and sand dollars
-have no arms, but five rows of tube feet that function in movement

Question 6

what are the traits of the class crinoidea? what animals are these?

Answer 6

-sea lilies and feather stars
-live attached to a substrate by a stalk