What structures separate the brain from the skull?

The meninges are the protective membranes that surround the brain and spinal cord, serving as a critical barrier between the central nervous system and the surrounding structures, including the skull. These membranes consist of three layers: the dura mater, arachnoid mater, and pia mater. The dura mater is the outer layer, providing a tough protective covering, while the arachnoid mater and pia mater provide additional cushioning and vascular support.

This protective system is essential for maintaining the health of the brain by helping to prevent injury from mechanical impact, restricting the entry of pathogens, and aiding in the regulation of cerebrospinal fluid, which also serves to cushion the brain. The function of the meninges is vital for preserving the intricate neuronal connections and overall function of the brain.

In contrast, nerve endings, blood cells, and bone marrow do not serve the same protective function as the meninges. Nerve endings are involved in sensory and motor functions, blood cells are critical for circulation and immune response, and bone marrow is primarily involved in the production of blood cells. Thus, none of these structures provide the same level of protection and separation from the skull as the meninges do.