The document provides information about the phylum Echinodermata: - Echinoderms are radially symmetric and marine invertebrates with an endoskeleton and water vascular system. There are five classes: sea stars, brittle stars, sea urchins, sea cucumbers, and sea lilies. - They have various methods of movement, digestion, respiration, circulation, and reproduction. Many can regenerate lost body parts. Echinoderms play important ecological roles through predation and grazing.