The kidneys regulate the fluid and electrolyte balance of the body by continually filtering the blood. This is vital to maintain a constant extracellular fluid volume and composition.
To perform this important function they are able to:
- excrete or conserve salt and water;
- control body pH, and
- free the body of waste products of metabolism.
There are three main processes that enable the kidneys to filter the blood. These are Glomerular filtration, Tubule secretion and Tubule resorption.