The choroid plexus is a network of cells located in the ventricles of the brain. Its primary function is to produce cerebrospinal fluid (CSF), which cushions the brain and spinal cord, providing protection and maintaining stable pressure within the central nervous system. In addition to producing CSF, the choroid plexus plays a role in filtering blood and regulating the composition of the fluid surrounding the brain. This helps to remove waste products and deliver essential nutrients, contributing to the overall health of the nervous system.