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What Is the Ethmoid Bone?

The ethmoid or ethmoidal bone is a pnumatized part of the human skull, technically one of the pieces that make-up the neurocranium. It constitutes to portions of the nasal cavity, cranium floor, and eye sockets. Pnumatized bone are bones that have air-filled cavities, making them much lighter when compared to other bones.

There are four portions to the ethmoidal bone the perpendicular plate, cribriform plate, and the twin labyrinths. These structures form the septum of the nose, bottom of the cranial space, and some of the orbital structure of the eye sockets. There are also other structures that are cloasly linked to the ethmoid bone due to their proximity. These structures are the crista galli and turbinate bones. Crista galli, also know as cock’s comb, is connected to the cribriform plate and provides an anchoring point for some of the tissues that keep the brain with in the skull. The turbinate bones, extending from the ethmoid bone into the nasal cavity, provide support for important mucous membranes which contribute to person’s sense of smell.

Since the the ethmoid bones are pnumatized they are not as tough as other bones and may become injured easily. This could lead to a loss or difficulty in a person’s sense of smell. At worst such an injury could kill a person, such as when someone is punched in the nose with proper direction and sufficient force to direct the shattered pieces of the ethmoid into the brain.

The belief that humans evolved from lower life forms is enforced by the presence of bits of magnetic metal, specifically iron oxide, in the human ethmoidal bone. This is very similar to birds and fish which have the same pieces of metal in their heads. This metal is believed to be of use in biomagnetic navigation, one of the ways by which these animals are able to travel over long distances with accuracy.

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