Which one of the following is bone of the brian case ?
a- lacrimal bone c- maxillary bone a- partictal bone b- zygomatic bone
The correct answer and explanation is:
The correct answer is c. parietal bone.
The parietal bones are part of the skull that form the sides and roof of the cranium. They are two large bones located on the upper sides of the head and are positioned above the temporal bones. These bones play a critical role in protecting the brain, particularly the cerebrum, which is the largest part of the brain. The parietal bones meet at the top of the head at a joint called the sagittal suture and connect with other bones of the skull such as the frontal, occipital, and temporal bones.
In contrast, the other bones listed are not part of the braincase:
- Lacrimal bone: This bone is found in the eye socket (orbit) and forms part of the medial wall of the orbit. It is involved in the structure of the eye socket and tear drainage system, but it is not part of the braincase.
- Maxillary bone: This bone forms the upper jaw and the central part of the face. It is involved in the structure of the mouth, teeth, and nasal cavity but does not protect the brain.
- Zygomatic bone: Also known as the cheekbone, it forms part of the structure of the face, specifically the prominence of the cheeks. It contributes to the lateral wall and floor of the orbit but does not protect the brain.
The parietal bones are essential for protecting the brain and are located in the cranium, which encases and shields the brain. Along with the frontal, occipital, and temporal bones, the parietal bones form the rigid structure known as the skull, which provides a protective casing for the brain and supports the face and sensory structures.