Nontoxic waste materials may either be retained, released, or recycled in other metabolic activities. Aid in temperature regulation of the body. Excretes urinelike wastes. Perspiration is only incidentally excretory, its primary function is that of temperature regulation. This absorption of heat lowers body temperature.
Temperature regulation is an example of homeostasis.
They excrete most of the urea. They control the concentration of most of the constituents of the body fluids.