- Membranous labyrinth is divided into three subcompartments:
- membranous semicircular ducts
- utricle and saccule
- membranous cochlea (cochlear duct)
- There are three fluid-filled spaces:
- Endolymphatic spaces (scala media) with endolymph, contained within the membranous labyrinth
- Perilymphatic space (scala vestibular and scala tympani) with perilymph, lying between the wall of the bony labyrinth and the wall of membranous labyrinth
- Cortilymphatic space with cortilymph, lying within the organ of Corti
Location: oval-shaped appendage on the lateral surface of the head.
Function: sound localization and amplification.
Composition: thin skin with hair follicles, sweat glands, and sebaceous glands covers supporting structure of elastic cartilage
Location: between the auricle and tympanic membrane
Composition: skin that contains hair follicles, ceruminous - modified sweat glands, and sebaceous glands covers supporting structure of elastic cartilage (lateral one-third) or bone (medial two-thirds)
Location: separates the external auditory canal from the middle ear
Function: sound in the form of airwaves causes the membrane to vibrate, and these vibrations are transmitted to the attached auditory ossicles
Composition: the layers from outside to inside
Location: cross the space of middle ear in series and connect the tympanic membrane to the oval window
Function: help to convert sound waves (vibrations in air) to mechanical (hydraulic) vibrations in tissues and fluid-filled chambers
Composition: movable joints connect the bones:
Location: connects the middle ear to the nasopharynx
Function: allow pressure in the middle ear to equilibrate with atmospheric pressure.
Composition: lined with ciliated pseudostratified columnar epithelium with small mass of lymphatic tissue
Location: three sensory regions of the semicircular ducts in the ampullae of the semicircular canals
Function: sensors of angular movement
Composition: the ridge of epithelium that is oriented perpendicular to the long axis of the semicircular canal
Location: saccule and utricle of the vestibule
Function: sensors of gravity and liner movement
Composition: the innervated sensory thickenings of the epithelium facing the endolymph
Location: the middle compartment in the cochlear canal
Composition: appears in transverse section as a triangular space.
Location: on the floor of scala media
Function: sound perception
Composition: complex epithelial layer