The plate-like structures in the ventricles of the brain are called "choroid plexuses." The choroid plexuses are specialized structures that produce cerebrospinal fluid (CSF), a clear and colorless fluid that surrounds the brain and spinal cord. CSF serves various functions, including providing buoyancy and protection for the central nervous system, aiding in nutrient and waste exchange, and serving as a cushion against mechanical injury. The choroid plexuses are found in the lateral, third, and fourth ventricles of the brain.
