The sphenoid bone creates some of the lateral cranium exterior on both the right and left sides between the temporal, parietal, and frontal bones. The sphenoid bone is a central bone in the skull located toward the anterior, but posterior to the ethmoid bone. Image E shows the anterior view of the skull and image F shows the superior view of the cranium interior with the anterior of the skull at the top of the image. Images E and F highlight the ethmoid bone in red and point to important structures of the ethmoid bone. These structures are visible in the cranium interior. In this diagram, you can see the cribriform plates, containing olfactory foramina, are located on either side of crista galli. Diagram D shows a simplified version of the ethmoid bone from an anterior view. Crista galli, an upward projection of the ethmoid bone, can be observed in the interior of the cranium and the perpendicular plate and middle nasal concha in the nasal cavity. Diagram C is an illustration of the ethmoid bone alone with an anterior view. Image B highlights the ethmoid bone in red with an anterior view. Image A highlights the ethmoid bone in red with a lateral view. Small segments of the ethmoid bone also make up medial regions of each of the right and left orbits or eye sockets.Ībove: This figure provides images depicting the location of the ethmoid bone and its structures. I are positioned on either side of crista galli on top of the two cribriform plates.

The two cribriform plates are separated by crista galli, a superior-pointing projection of the ethmoid bone that can be seen inside the cranial cavity. I olfactory nerve), transmitting scent information to the brain. The olfactory foramina are passageways where axons of these scent-sensing neurons can pass into the cranial cavity and bring olfactory (scent) information to the olfactory bulbs of cranial nerve I ( C.N. At the inferior aspects of the cribriform plates, olfactory epithelia are equipped with olfactory sensory neurons collecting scent information. This separation is created by the cribriform plates of the ethmoid bone, two flat regions that house numerous pin-hole foramina called olfactory foramina. The ethmoid bone also creates separation between the nasal cavity and the cranial cavity. The perpendicular plate articulates with part of the vomer bone which form the inferior portion of the nasal septum. A medial, inferior-pointing projection called the perpendicular plate of the ethmoid bone creates the superior aspect of the septum separating the right and left nasal cavities. There are also paired medially-projecting inferior nasal conchae, but these are a part of the maxilla bone, a facial bone. These conchae form paired canals or passageways (right and left) in the nasal cavities for air passage called nasal meatuses ( superior, middle, and inferior nasal meatuses).

The ethmoid bone is located deep in the anterior of the skull forming part of the nasal cavity, including the paired superior nasal conchae (right and left) and middle nasal conchae (right and left), bony projections that point medially into the nasal cavities.

Bones of skull