What anatomical structure protects the brain and contains cerebrospinal fluid?

The anatomical structure that protects the brain and contains cerebrospinal fluid is the meninges. The meninges consist of three layers: the dura mater, arachnoid mater, and pia mater. These layers encase the brain and spinal cord, providing a protective barrier against physical impacts and infections. Between the arachnoid mater and pia mater lies the subarachnoid space, which is filled with cerebrospinal fluid (CSF). This fluid cushions the brain, helps maintain intracranial pressure, and provides essential nutrients while removing waste.

While the skull is also a protective structure, its primary role is to encase the brain physically, providing a hard barrier against external trauma. It does not contain cerebrospinal fluid. The ventricles are fluid-filled cavities within the brain that produce cerebrospinal fluid but are not responsible for protecting the brain in the same way the meninges do. The cortex refers to the outer layer of brain tissue involved in higher brain functions but does not serve a protective role or contain CSF.