Echinoderms and Marine Arthropods Unit Study Guide

Echinodermata meaning

Spiny - skin

Asteroidea

Cushion star, spiny starfish

Holotheroidea

Giant California Sea cucumber, Hairy sea cucumber

Echinoidea

Sand dollar, Purple sea urchin, Long spined urchin

Water vascular system

Uses water pressure to help with movement, feeding, and gas exchange

Keystone Species

Organisms that play a crucial role in the ecosystem, if eliminated everything could fall apart

Holothuroidea Diet

Debris in the benthic zone

Asteroidea Diet

Bivalves, barnaclesE

Echinoidea Diet

Herbivores, eat algae

Barnacle

• Only sessile crustacean

• Can attach to anything

• Cirripeds: Feathery appendages that filter out food to eat

• Longest penis relative to its size

Copepods

• Largest group of crustaceans

  • Most abundant zooplankton in the ocean

Krill

• Filter feeders

• ound in the open ocean

Swimmerets

Arms used for sensing

Walking legs

Walking and movementE

Maxillipeds

Appendages modified for eating

Chelipeds

Claws used for pinching