GENERAL HISTOLOGY

Detailed explanation-1: -The water vascular system is a hydraulic system used by echinoderms, such as sea stars and sea urchins, for locomotion, food and waste transportation, and respiration. The system is composed of canals connecting numerous tube feet.

Detailed explanation-2: -Define Echinoderm. Invertebrates with an internal skeleton and a system of fluid-filled tubes called a water vascular system. Examples: sea cucumbers, sea starts, sea urchins, and sand dollars.

Detailed explanation-3: -Echinoderms are characterized by a unique coelomic water vascular system. This is a hydraulically controlled system consisting of a circumoral ring around the esophogus with connecting radial canals each leading to an ambulacrum.

Detailed explanation-4: -All echinoderms have a water-vascular system, a set of water-filled canals branching from a ring canal that encircles the gut. The canals lead to podia, or tube feet, which are sucker-like appendages that the echinoderm can use to move, grip the substrate, or manipulate objects.

Detailed explanation-5: -An echinoderm moves by using many tube feet. Tube feet are small, delicate projections attached along the side of a water-filled tube called a radial canal. Figure 3.85 shows some examples of echinoderm tube feet. Tube feet extend through the small holes in the skeleton to the outside.