Excretion and the Kidneys

The excretory system is responsible for eliminating the waste products of metabolism from your body. The primary organs in charge of this important task are the kidneys, the skin, the liver, and the lungs. These organs regulate the chemical composition of body fluids by removing metabolic wastes and conserving the normal amounts of nutrients, water, and salts, necessary for harmony And balance of the human body. The liver performs a vital excretory function in addition to its digestive functions. It gets rid of unwanted wastes in the body. It is in charge of breaking down toxic chemicals and drugs that may be harmful to the body. The liver also changes ammonia, a poisonous gas, to urea, a harmless liquid and secretes bile which breaks down fats. Wastes, gases, such as carbon dioxide, which are carried through the veins, are removed from the body by the lungs during respiration while dead cells and waste products such as excess water, salt, urea and uric acid are removed from the body in sweat through the skin. The kidneys are the most important organs of the excretory system. These two bean-shaped, reddish-brown organs located on either side of the spinal column near the lower back, act as blood filters. All blood circulating through the human body eventually passes through the kidneys where harmful substances are removed from the bloodstream while retaining the substances that make the body fit and healthy The kidneys receive oxygenated blood traveling from the largest artery in the human body (the aorta), filter the blood, and circulate it back to the heart with the appropriate amounts of fluids, nutrients and chemicals for distribution and use throughout the body. During the process, metabolic waste products which include unwanted water, minerals, and urea, are filtered from the blood by the kidneys to produce a liquid commonly known as urine. The kidneys then transfer the urine through two tubes (ureters) into the bladder where the urine is stored until muscular contraction forces the urine out of the body through the urethra by a process we call urination.