Functions of Kidney : The main function of the kidneys is to filter the blood and produce urine by reabsorbing useful and essential substances for the body from the filtered liquid. Apart from producing urine, it also performs the following functions :
1. Along with excreting the end products of food metabolism-water, urea and uric acid, it also excretes some drugs, poisons and chemical substances harmful to the body.
2. Maintains the balance of water and electrolytes in the body.
3. By regulating water balance in the entire body, blood plasma volume is kept stable.
4. Controls the acid-base balance in the body.
5. Help in maintaining the osmotic pressure of the fluid present in the body.
6. They produce an enzyme called renin which regulates blood pressure.
7. Control the chemical composition of blood and other body fluids (extracellular fluids) and keep their concentration stable.
8. By producing ammonia, the hydrogen volume of blood in the body is increased.