Kidneys Royalty-Free Stock Image

The kidneys are bean-shaped organs that serve several essential regulatory roles in vertebrates. Their main function is to regulate the balance of electrolytes in the blood, along with maintaining pH homeostasis. They also remove excess organic molecules from the blood, and it is by this action that their best-known function is performed: the removal of waste products of metabolism. Kidneys are essential to the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and regulation of blood pressure (via maintaining the salt and water balance).