renal cortex

The renal cortex is the outer layer of the kidney, acting as the site where blood is filtered to form urine. It contains tiny structures called nephrons, which are the functional units of the kidney. Blood enters the nephrons, where waste products and excess substances are removed, while useful substances like water and salts are reabsorbed into the bloodstream. The cortex's role is essential for maintaining the body's fluid and electrolyte balance, removing waste, and supporting overall kidney function. It is protected by and lies just beneath the kidney's outer surface.