The purpose of the cortical nephrons is to filter and clean blood from the kidneys. The nephrons remove unneeded water, waste and other substances from the blood. Cortical nephrons also return beneficial substances to the body, such as sodium, potassium and phosphorous, if concentrations are low.
The cortical nephrons are located in the outside edge of the kidney and are distinguished from the juxta-medullary nephrons located at the cortico-medullary junction. Each nephron is composed of two structures, a glomerulus and a kidney tubule. The filtering of blood occurs at the glomerulus, while the tubule transports the waste products and recyclable fluids.