Øreknoglerne

Øreknoglerne, also known as the ossicles, are three tiny bones in the middle ear of mammals. They are the malleus (hammer), incus (anvil), and stapes (stirrup). These bones form a chain connecting the tympanic membrane (eardrum) to the oval window, an opening in the bony labyrinth of the inner ear.

The primary function of the øreknogler is to efficiently transmit sound vibrations from the air in the external ear canal to the fluid-filled inner ear. The eardrum vibrates when struck by sound waves. This vibration is then amplified and transferred through the malleus, incus, and stapes. The lever action of the ossicles and the difference in surface area between the eardrum and the oval window contribute to this amplification, allowing for the detection of even faint sounds.

The malleus is attached to the eardrum, while the incus connects the malleus to the stapes. The stapes, the smallest bone in the human body, is inserted into the oval window. The movement of the stapes against the oval window creates pressure waves in the fluid of the cochlea, the auditory portion of the inner ear, which are then interpreted as sound by the brain. Muscles attached to the ossicles, the tensor tympani and the stapedius, can contract to dampen these vibrations, protecting the inner ear from excessively loud sounds.