BIOL370 Study Guide - Final Guide: Glucocorticoid, Salt Gland, Vasodilation
10 Feb 2015
School
Department
Course
Professor
Document Summary
Aqueous environments: freshwater (1-50 mosm/l) & seawater (1000mosm/l) Hagfish are isosmotic but can regulate some ions: e. g. Elasmobranchs are isosmotic/hyperosmotic but can regulate inorganic ions ionoregulation . Perturbing solute urea vs. tmao: e. g. Bony fish are hypoosmotic & ionoregulate major ions (na+, k+ & cl-) Pna- (pavement cells): transport na+ from water to blood. H+ moves to the basolateral side, acidifies the membrane to allow the intake of na+ via na+/h+ exchanger. Pna+ (chloride cells): transport cl- & ca2+ from water to blood. Co2 + h2o carbonate anhydrase hco3. Travels to the basolateral side, cl- is brought in via the cl-/hco3 can enters via the ca2+ channel. Seawater osmoregulation (hypoosmotic body fluid threat: shrinking: salt is absorbed at the gut (apical nkcc & basolateral na+/k+ atpase, excessive salt is eliminated by. Urine is isotonic to blood but rich in divalent ions not well transported via gills . Gill and kidney conserves water & eliminates salt.
