Final answer:
The skull consists of 22 bones, which include eight cranial bones: the frontal bone, paired parietal bones, paired temporal bones, the occipital bone, the sphenoid bone, and the ethmoid bone. These bones not only protect the brain but also contribute to the cranial structure and facial formation.
Step-by-step explanation:
Composition of the Cranial Bones
The skull is a complex structure that provides protection for the brain and supports the facial features. It is comprised of 22 bones in total, of which eight belong to the cranium or the brain case. These eight cranial bones include one frontal bone, two parietal bones, two temporal bones, one occipital bone, one sphenoid bone, and one ethmoid bone. The parietal and temporal bones come in pairs, whereas the frontal, occipital, sphenoid, and ethmoid are single, unpaired bones. The brain case serves the crucial role of encasing and safeguarding the brain within the cranial cavity.
Each of these bones contributes to the integrity of the cranium, through joint sutures such as the sagittal, coronal, lambdoid, and squamous sutures. These sutures are filled with dense, fibrous connective tissue that unites the bones securely. The sphenoid and ethmoid bones are particularly notable as the sphenoid helps form the eye sockets and the ethmoid separates the nasal cavity from the brain.