Water vascular system

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.[1] The system is composed of canals connecting numerous tube feet. Echinoderms move by alternately contracting muscles that force water into the tube feet, causing them to extend and push against the ground, then relaxing to allow the feet to retract.[1][2]

The exact structure of the system varies somewhat between the five classes of echinoderm. The system is part of the coelomic cavities of echinoderms, together with the haemal coelom (or haemal system), perivisceral coelom, gonadal coelom and perihaemal coelom.[3]

Other terms sometimes used to refer to the water vascular system are "ambulacral system"[4][5][6] and "aquiferous system". In the past, "aquiferous system" was also used to refer to many unrelated invertebrate structures,[7][8] but today, it is restricted to water channels in sponges[9] and the hydrostatic skeleton of some mollusks like Polinices.[10]

  1. ^ a b Solomon, Eldra; Linda Berg; Diana Martin (2002). Biology. Brooks/Cole.
  2. ^ Dale, Jonathan (2000). "Starfish Science".
  3. ^ "Macrobenthos of the North Sea - Echinodermata > Introduction". etibioinformatics.nl.
  4. ^ "Echinoderma" . Encyclopædia Britannica. Vol. 08 (11th ed.). 1911.
  5. ^ Harrison, F.W. & Chia, F.-S. (1994). Microscopic Anatomy of Invertebrates. Vol. 14: Echinodermata. Wiley-Liss, New York, [1].
  6. ^ Ax, Peter. (2003). Multicellular animals: the phylogenetic system of the metazoa. Akademie der Wissenschaften und der Literatur, Mainz, vol. 3., [2].
  7. ^ Carpenter, William Benjamin (1854). Principles of comparative physiology. 4th ed. London: John Churchill, [3].
  8. ^ Siebold, C.Th. von (1874). Anatomy of the Invertebrata. Translated by W.I. Burnett. Boston: J. Campbell, [4].
  9. ^ Bergquist, Patricia R. (1978). Sponges. London: Hutchinson, [5].
  10. ^ Voltzow, J. (1994). Gastropoda: Prosobranchia. In: Microscopic Anatomy of Invertebrates, Harrison, F.W. & Kohn, A.J. (eds.), Vol. 5: Mollusca I. Wiley-Liss, New York: 111–252, [6].