THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The kidney and urinary systems help the body to get rid of liquid waste called urea. They also help to keep chemicals (such as potassium and sodium) and water in balance.

Detailed explanation-2: -The urinary bladder stores the urine until it gets a voluntary signal from the CNS. The urge to pass the urine is caused when the urinary bladder set up reflexes. That is, it stimulates the sensory nerve present at the edge of the urinary bladder, and sends the signals to the CNS.