BEFORE WE START TO EXPLAIN THE WATER VASCULAR SYSTEM OF THE ECHINODERM, WE MUST CLARIFY A FEW THINGS. FIRST, THE "BLOOD" OF ECHINODERMS IS MOSTLY COMPOSED OF SEAWATER(animals.nationalgeographic.com). SECOND, THE MOTION OF THE WATER THROUGH THE CIRCULATORY AND RESPIRATORY SYSTEMS IN ECHINODERMS IS ACHIEVED THROUGH CILIA AND FLAGELLA THAT LINE THE SYSTEM OF THE ECHINODERM AND FORCE IT A CERTAIN DIRECTION (www.ncbi.nlm.nih.gov). THIRD, ECHINODERMS PUMP WATER THROUGH THEMSELVES AS BOTH A RESPIRATORY PROCESS (ATTAINING OXYGEN FROM THE WATER AND EXPORTING CARBON DIOXIDE), AND A CIRCULATORY PROCESS (WATER ACTS AS BLOOD BY WHICH THE ECHINODERM CAN MOVE).
IN THE WATER VASCULAR SYSTEM OF AN ECHINODERM, THERE ARE 4 MAIN ASPECTS: THE CIRCUMORAL RING, THE RADIAL CANALS, THE MADREPORITE, AND THE AMPULLAE/TUBE FEET (deepseanews.com). THE CIRCUMORAL RING IS THE RING THAT SURROUNDS THE STOMACH OF THE ECHINODERM AND PUMPS WATER THROUGH THE WATER VASCULAR SYSTEM OF THE ECHINODERM. THE ARMS OF THE ORGANISM CONTAIN THE RADIAL CANALS. THESE RADIAL CANALS ARE CONNECTED TO THE TUBE FEET, AND HELP TO PUMP WATER THROUGH TO THEM(www.ucmp.berkeley.edu). THIRD, THE MADREPORITE, WHICH IS LOCATED NEXT TO THE CIRCUMORAL RING, WHICH IS RESPONSIBLE FOR CONTROLLING SOME OF THE WATER THAT COMES IN AND OUT OF THE WATER VASCULAR SYSTEM. LASTLY, THE AMPULLA AND TUBE FEET ON THE ECHINODERM STRETCH AND CONTRACT, WHICH IS HOW ECHINODERMS ACHIEVE LOCOMOTION. THE WATER IS THEN FORCED OUT THROUGH THE TUBE FEET, EXITING THE ORGANISM. (www.sfsu.edu)
(Animation from lcmrschooldistrict.com)
IN THE WATER VASCULAR SYSTEM OF AN ECHINODERM, THERE ARE 4 MAIN ASPECTS: THE CIRCUMORAL RING, THE RADIAL CANALS, THE MADREPORITE, AND THE AMPULLAE/TUBE FEET (deepseanews.com). THE CIRCUMORAL RING IS THE RING THAT SURROUNDS THE STOMACH OF THE ECHINODERM AND PUMPS WATER THROUGH THE WATER VASCULAR SYSTEM OF THE ECHINODERM. THE ARMS OF THE ORGANISM CONTAIN THE RADIAL CANALS. THESE RADIAL CANALS ARE CONNECTED TO THE TUBE FEET, AND HELP TO PUMP WATER THROUGH TO THEM(www.ucmp.berkeley.edu). THIRD, THE MADREPORITE, WHICH IS LOCATED NEXT TO THE CIRCUMORAL RING, WHICH IS RESPONSIBLE FOR CONTROLLING SOME OF THE WATER THAT COMES IN AND OUT OF THE WATER VASCULAR SYSTEM. LASTLY, THE AMPULLA AND TUBE FEET ON THE ECHINODERM STRETCH AND CONTRACT, WHICH IS HOW ECHINODERMS ACHIEVE LOCOMOTION. THE WATER IS THEN FORCED OUT THROUGH THE TUBE FEET, EXITING THE ORGANISM. (www.sfsu.edu)
(Animation from lcmrschooldistrict.com)
Picture from www.esu.edu