What is the outermost brain membrane known for its resilience?

The outermost brain membrane is known as the dura mater. It is a tough and resilient membrane that provides a protective layer for the brain and spinal cord. The dura mater is composed of dense connective tissue, which affords it durability and the ability to withstand various physical stresses, making it an effective barrier against injury and infection.

In addition to its protective qualities, the dura mater also plays a critical role in forming compartments within the skull, helping to stabilize the brain and prevent excessive movement during head trauma. Its position as the outermost layer means it is the first line of defense against external forces that could impact the central nervous system.

The other layers of the meninges, which are the arachnoid and pia mater, offer different functions. The arachnoid, for instance, is a web-like structure that provides cushioning and is involved in the circulation of cerebrospinal fluid, while the pia mater is a delicate membrane that closely adheres to the surface of the brain, supplying nutrients and oxygen. The cerebrum refers to the brain's largest part and is not a protective membrane at all. Thus, the distinction of the dura mater as the outermost layer highlights its critical role in protecting the delicate structures of the brain.