Main source of Nitrogen in urine and is excreted by the body as a waste product from your kideys.
In humans, soluble wastes are excreted primarily by the urinary system and, to a lesser extent in terms of urea removed, by perspiration. The urinary system consists of the kidneys, ureters, urinary bladder, and urethra. The system produces urine by a process of filtration, reabsorption, and tubular secretion.  Urea (NH2)2CO is a chemical that comes from the breakdown of proteins. It is the main source of Nitrogen in urine and is excreted by the body as a waste product from your kidn … eys.   Urea is a readily available source of Nitrogen so is used as a fertilizer and sometimes as a supplement to feed for stock.   . 60 people found this useful. Full Definition of EXCRETION. 1. : the act or process of excreting. 2. : something excreted; especially: metabolic waste products (as urea and carbon dioxide) that are eliminated from the body. See excretion defined for English-language learners. See excretion defined for kids. ADVERTISEMENT.  Urea is synthesized in the body of many organisms as part of the urea cycle, either from the oxidation of amino acids or from ammonia. In this cycle, amino groups donated by ammonia and L-aspartate are converted to urea, while L-ornithine, citrulline, L-argininosuccinate, and L-arginine act as intermediates. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals, and is the main nitrogen-containing substance in the urine of mammals. It is colorless, odorless solid, highly soluble in water, and practically non-toxic (LD50 is 15 g/kg for rats). Metabolism is chemical reactions taking place inside cells, including respiration. The body excretes three main waste materials. These are Carbon Dioxide, Urea and Water. Excretion is a very important feature to us because without it toxic substances will build up in our bodies and kill us. It also helps in maintaining the composition of body fluids. Urea: Chemical compound of carbon, hydrogen, nitrogen, and oxygen produced as waste by cells that break down protein. Ureter: Tube that carries urine from a kidney to the urinary bladder. Urethra: Duct leading from the urinary bladder to outside the body through which urine is eliminated. The kidneys, considered the main excretory organs in humans, eliminate water, urea, and other waste products from the body in the form of urine. Other systems and organs in the body also play a part in excretion. The Urea Cycle. About 80% of the excreted waste nitrogen is in the form of urea which is produced exclusively in the liver, in a series of reactions that are distributed between the mitochondrial matrix and the cytosol. The series of reactions that form urea is known as the Urea Cycle or the Krebs-Henseleit Cycle.  The excretory system is a system of organs that removes waste products from the body. When cells in the body break down proteins (large molecules that are essential to the structure and functioning of all living cells), they produce wastes such as urea (a chemical compound of carbon, hydrogen, nitrogen, and oxygen). The kidneys, considered the main excretory organs in humans, eliminate water, urea, and other waste products from the body in the form of urine. Other systems and organs in the body also play a part in excretion. Excretion and the liver Excretion in mammals Excretion is the removal of potentially harmful or toxic substances from the body. These substances are usually waste materials produced by complex chemical reactions taking place in living cells. Enzymes catalyse the reactions. The urea and water are released from the liver cells to the bloodstream and transported to the kidneys where the blood is filtered and the urea is passed out of the body in the urine. Urea is very soluble and a small molecule, so it is relatively easily passed out by the kidneys as a solution in water
https://en.wikipedia.org/wiki/Urine http://www.answers.com/Q/How_is_urea_excreted http://www.merriam-webster.com/dictionary/excretion https://en.wikipedia.org/wiki/Urea http://www.xtremepapers.com/revision/gcse/biology/excretion_in_humans.php http://www.scienceclarified.com/El-Ex/Excretory-System.html http://themedicalbiochemistrypage.org/nitrogen-metabolism.php http://www.scienceclarified.com/El-Ex/Excretory-System.html http://www.rsc.org/Education/Teachers/Resources/cfb/excretion.htm
where in the body is urea excreted