The urinary system is not just a solitary working system. It also works with the lungs (respiratory system) and intestines (digestive system) to keep all body chemicals and water in balance. The urinary system removes a type of waste knowen as urea (the biproduct of the body metabolizing protein) from the blood. Urea is produced when foods protein packed foods, like meat and eggs, are broken down.
(Chamical structer of Urea)