What structure encloses and protects the brain?

The structure that encloses and protects the brain is the skull. The skull is a bony structure that forms the head, providing a rigid barrier to safeguard the brain from injury. It also supports the structures of the face and serves as an attachment point for muscles involved in facial expressions and movements.

The cranial part of the skull encases the brain and is composed of several bones fused together, creating a protective cavity. This anatomical feature is crucial for maintaining the integrity of the brain, as it is a delicate organ that requires protection from external forces. In contrast, the vertebrae protect the spinal cord, the rib cage safeguards the heart and lungs, and the pelvis provides support for the lower body and protects reproductive and urinary organs, but none of these structures fulfill the role of enclosing and protecting the brain specifically.