The kidneys are responsible for maintaining homeostasis by regulating the levels of essential body fluids, electrolytes, and hormones in the blood. The kidneys work to filter out waste products from the blood and then excrete them from the body. They also regulate the amount of water in the body and help to balance the levels of electrolytes in the body. They also produce hormones like erythropoietin and renin which help to regulate blood pressure and blood volume. In addition, the kidneys also help to regulate blood acidity and pH levels by controlling the production of bicarbonate ions.