Th e body must rid itself of the waste products of cellular activity. The process of removing metabolic wastes, called excretion, is just as vital as digestion in maintaining the body's internal environment. Thus, the urinary system not only excretes wastes but also helps maintain homeostasis by regulating the content of water and other substances in the blood.
The main waste products that the body must eliminate are carbon dioxide, from cellular respiration, and nitrogenous compounds, from the breakdown of proteins. The lungs excrete most of the carbon dioxide, and nitrogenous wastes are eliminated by the kidneys. The excretion of water is necessary to dissolve wastes and is closely regulated by the kidneys, the main organs of the urinary system.
Humans have two bean-shaped kidneys, each about the size of a clenched fist. The kidneys are located one behind the stomach and the other behind the liver. Together, they regulate the chemical composition of the blood.
Was this article helpful?
Discover How To Sleep In Peace And Harmony In A World Full Of Uncertainty And Dramatically Improve Your Quality Of Life Today! Finally You Can Fully Equip Yourself With These “Must Have” Tools For Achieving Peace And Calmness And Live A Life Of Comfort That You Deserve!