The urinary system works with the digestive system and in other systems in your body. It releases the waste from the food they digest and it also works with the circulatory system. It works in other systems in the body to help the body maintain the homeostasis says the Biologists. The waste product is kept dissolved in the liquid (water) and in mammals is stored in a bladder. The work of the kidney inside the body is to maintain acid and water-salt levels of the blood. It releases the waste in the body and it also filters the blood inside of you.