What is the name of the fluid that surrounds and protects the brain and spinal cord?

Cerebrospinal fluid is a clear, colorless liquid that surrounds and cushions the brain and spinal cord. Its primary function is to provide buoyancy, reducing the effective weight of the brain and spinal cord, which helps prevent damage due to the gravitational forces acting on them. Additionally, cerebrospinal fluid plays a crucial role in protecting these vital structures from injury, maintaining a stable internal environment, and facilitating the removal of metabolic waste.

In contrast, synovial fluid lubricates joints, supporting joint health and facilitating smoother movement, which is not related to the protection of the central nervous system. Serous fluid is a lubricating fluid found between the serous membranes lining the body cavities, and while it helps reduce friction between organs, it does not serve the same protective purposes as cerebrospinal fluid. Plasma is the liquid component of blood, primarily involved in transporting nutrients, hormones, and waste products throughout the body, rather than providing direct protection to the brain and spinal cord.