What is the main function of the renal cortex?

The renal cortex plays a crucial role in the functioning of the kidneys, primarily through its involvement in filtering blood and housing the nephrons. Nephrons, the functional units of the kidney, are responsible for the filtration of blood, reabsorption of essential substances, and the secretion of waste products. The renal cortex contains the glomeruli, which are the initial site of blood filtration, as well as the proximal and distal convoluted tubules, where important processes of reabsorption and secretion occur.

The cortex's structure allows for the efficient processing of blood; therefore, its main function is intimately linked to maintaining homeostasis in the body through the regulation of fluid, electrolytes, and waste elimination. While other parts of the kidney, such as the medulla, are involved in urine concentration, and different parts of the system may be associated with hormone production or urine storage, these processes are not the primary roles of the renal cortex.