Final answer:
Ependymal cells, derived from neuroepithelium, form the lining of the brain's ventricles where they help produce and regulate cerebrospinal fluid (CSF) and form part of the blood-brain barrier (BBB).
Step-by-step explanation:
Ependymal cells are a type of glial cells derived from the neuroepithelium that line the ventricles of the brain and the central canal of the spinal cord. They are crucial in the production and regulation of cerebrospinal fluid (CSF), which circulates through the central nervous system (CNS). These cells have a pivotal role within the blood-brain barrier (BBB), particularly at the choroid plexus, a specialized structure where they filter components of the blood to produce CSF. The ependymal cells' epithelial-like morphology, including their tight junctions and ciliated apical surface, facilitates this process and helps move CSF through the ventricular system.