Echinoderms

Question 1

What are special traits in phylum Chordata, how do they help them survive?

Answer 1

1) tube feet (water vascular system): allows them to attach to prey and hold on without using much energy
2) regeneration: can make new limbs when injured and can regenerate their digestive tract when it’s been expelled
3) radial symmetry: can move in any direction without turning around.

Question 2

List characteristics of Asteroidea

Answer 2

1) multiple arms/rays
2) use tube feet for movement
3) eat bivalves and other small prey

Question 3

List characteristics of Crinoidea

Answer 3

1) some are sessile as adults
2) use tentacles coated with slime for filter feeding
3) feed on algae and detritus (herbivores)

Question 4

List characteristics of Echinoidea

Answer 4

1) adults burrow into rocks, sand, etc
2) use tube feet for movement
3) ball or disc shaped

Question 5

List characteristics of Holothuroidea

Answer 5

1) may release internal organ when threatened and the regenerate them
2) burrow into sand, gravel, etc
3) use tube feet for movement

Question 6

List characteristics of Ophiuroidea

Answer 6

1) have multiple rays

2) use rays for movement

Question 7

What are the classes of Echinodermata

Answer 7

1) Asteroidea: sea stars
2) Ophiuroidea: brittle stars
3) Crinoidea: sea lilies and feather stars
4) Echinoidea: sea urchins and sand dollars
5: Holothuroidea: sea cucumbers