Nitrogenous Wastes

Nitrogenous Wastes

1. Ammonia

   • Extremely toxic; requires vast amounts of water to dilute
   • Low cost of energy; mostly excreted by aquatic animals

2. Urea

   • Lower toxicity; NH4 + CO2 in the liver
   • Energetically costly

3. Uric Acid

   • Much lower toxicity; NH4 bound in a heterocyclic compound
   • High energetic cost; semi-water soluble - semi-solid paste

4. Wastes resulting from the breakdown of Proteins and Nucleic Acids to form nitrogenous wastes and amino acids