Question

a neuroglial cell that is a major component of the blood - brain barrier is the:
a ependymal cell
b astrocyte
c oligodendrocyte
d macrophage
e microglial cell

Explanation:

• Ependymal cells line the ventricles of the brain and central canal of the spinal cord and produce cerebro - spinal fluid.
• Astrocytes have processes that end on blood vessels and help in the formation and maintenance of the blood - brain barrier.
• Oligodendrocytes form myelin sheaths around axons in the central nervous system.
• Macrophages are immune cells (not neuroglial cells in the strict sense of CNS neuroglia classification here, though they can be in the CNS as part of immune response).
• Microglial cells are the resident immune cells of the central nervous system, phagocytosing debris.

Answer:

B. astrocyte