Final answer:
The protective meninges from the outermost to the innermost are the dura mater, arachnoid mater, and pia mater, which guard the brain and spinal cord alongside cerebrospinal fluid.
Step-by-step explanation:
The meninges are a three-layered membrane that encloses and protects the brain and spinal cord. From the outermost to the innermost, the meninges are named: the dura mater, the arachnoid mater, and the pia mater.
The dura mater is a thick, fibrous layer that is the outermost covering, providing robust protection for the brain and spinal cord. It is attached to the inner surfaces of the cranium and vertebral column. The arachnoid mater is a thinner, web-like layer situated between the dura and the pia mater. Lastly, the pia mater is a delicate membrane that directly contacts and closely adheres to the surface of the brain and spinal cord, following all of its contours.
Between the arachnoid mater and the pia mater, there is a space filled with cerebrospinal fluid (CSF), which acts as a cushion and shock absorber for the brain and spinal cord, contributes to chemical stability, and provides buoyancy to the brain.