Excretory System

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Excretory system
DEFINITION
The excretory system is a passive biological system that removes excess, unnecessary materials from an organism, so as to help maintain homeostasis within the organism and prevent damage to the body. It is responsible for the elimination of the waste products of metabolism as well as other liquid and gaseous wastes, as urine and as a component of sweat and exhalation. As most healthy functioning organs produce metabolic and other wastes, the entire organism depends on the function of the system; however, only the organs specifically for the excretion process are considered a part of the excretory system. Parts and functions

The Skin
The skin is responsible for producing sweat, which helps regulate the salt concentration in the body. When you sweat, the salt helps evaporate the water and, in turn, cools off the body.

The Liver
The liver is part of the digestion system, but also plays a role in the excretory system. The liver has a small organelle called a peroxisome, which is responsible for taking high levels of toxicity and converting them to less toxic substances. Bile is a waste product in this process and is used in the digestive process.

The Kidneys
The role of the kidneys is to remove nitrogenous wastes from the body. Nitrogenous means that it is rich in the element nitrogen. Nitrogen in high concentrations in the body can cause several problems such as joint pain, strokes or heart attacks. The kidney is made up three parts: the renal cortex, the renal medulla and the renal pelvis. All mammals have two kidneys. The kidney's primary function is to regulate various body fluids and salt concentration.

The Other Parts of the Excretory System
The excretory system also contains the ureter, which are two tubes that lead into the bladder. The bladder holds unnecessary wastes for storage. The urethra is where urine is expelled from the body.

Filtration
Blood is filtered through the kidneys by first traveling through the renal artery. The artery splits into many arterioles, which go to Bowman's Capsules that contain a bundle of capillaries called nephrons. The nephrons create a large bundle of capillaries called the glomerulus that filters the blood by taking out the toxins. Some toxins that are removed are ammonia, uric acid, medicines and antibiotics. This is also the site for reabsorbing amino acids, vitamins and water. Excretion

The renal pelvis takes the urine away from the ureter and stores it into the bladder. The bladder can expand as more liquid is stored. When full, the bladder sends nerves impulses to the brain and causes the sensation of being full. Urine is the liquid nitrogenous waste from the kidneys and is taken from the body through the urethra. Disease

The main function of the excretory system, also referred to as the urinary system, is to maintain a proper balance of body fluids through the excretion of waste products. Other functions include salt balance in the body and blood and the production of important hormones. The excretory system consists of the kidneys, bladder, ureters and urethra. Common excretory diseases can affect any part of the system and cause serious complications if left untreated. Kidney Stones

Kidney stones are hard masses that form in the urinary tract from crystals that have separated from the urine. The most common type of kidney stone is formed from calcium, but other types include a struvite stone or uric acid stone, according to the National Kidney and Urologic Diseases Information Clearinghouse. The exact cause of kidney stones is unknown, but those with certain genetic disorders, kidney disorders and recurrent urinary tract infections are more likely to develop kidney stones. Symptoms of kidney stones include extreme pain, cramping in the back and lower abdomen, nausea and vomiting. Most kidney stones can be passed by increasing daily fluid intake to two to three quarts of water per day. If stones are too large to pass with an...
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