GENERAL HISTOLOGY

Detailed explanation-1: -The Phylum Echinodermata is distinguished by characteristics such as spiny-skin, pentaradial symmetry, and an endoskeleton composed of calcareous ossicles. Given that all species in this phylum are exclusively marine dwellers, they also evolved a specialized water-vascular system.

Detailed explanation-2: -Although they may appear very different, echinoderms all have two major defining characteristics that set them apart from all other animals: a water vascular system and five-sided radial symmetry.

Detailed explanation-3: -A feature that is unique to this group is their water vascular system. They have water filled canals that end in the tube feet, enabling this group to anchor themselves to substrate such as rocks and corals. They use their tube feet to attach to rocks, but also for locomotion. All echinoderms have tube feet.

Detailed explanation-4: -Echinoderms have a unique water vascular system with tube feet. This allows slow but powerful movement.