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The Influence Of Environmental Ph And Bicarbonate Concentration On The Excretion Of Nitrogenous Waste Products In Two Species Of Freshwater Teleost, Paul D. Fabsits

Masters Theses

The catabolism of amino acids derived from dietary protein results in the production of ammonia and bicarbonate ion, waste products that an animal must eliminate. Often, animals excrete a nitrogenous waste product that is correlated with water availability: Freshwater fish, living where water is abundant, usually excrete ammonia while terrestrial animals excrete urea or uric acid. Recent studies report that fish inhabiting alkaline waters (pH 10) characterized by high bicarbonate concentrations do not excrete ammonia, instead synthesize urea, an energetically expensive process. The conversion to urea excretion by a normally ammonotelic animal is likely to be stimulated by a specific …