Explain the anatomy and function of the inner ear of humans.
#Revision_Q27
Answers
Answer:
The inner ear comprises of two functional units: the vestibular apparatus, consisting of the vestibule and semicircular canals which contains the sensory organs of postural equilibrium; and the snail-shell-like cochlea, which contains the sensory organ of hearing.
Que :-
Explain the anatomy and function of the inner ear of humans.
Ans :-
The human ear is called acoustic organ and it has two functions hearing and body equilibrium.
Anatomically the ear is made up of three parts:-
external ear,
middle ear
and inner ear
Anatomy and function of the inner ear of humans :-
1) The internal ear consists of the Labyrinth and vestibular apparatus.
2) The labyrinth consists of Bony Labyrinth and membranous Labyrinth.
3) These are filled with perilymph and endolymph respectively. The coiled portion of the Labyrinth is called cochlea.
4) The cochlea contains fluid filled three Chambers separated by Reissner's membrane and basilar membrane.
5 )The upper chamber towards vestibule is called scala vestibuli and the bottom chamber scala tympani are filled with perilymph.
6) The middle chamber is the scala media.
7) It is filled with endolymph while scala vestibuli and scala tymphnith are filled with perilymph.
8) The organ of corti is a pea sized the structure located on basilar membrane. ( floor of scala media )
9) The organ of corti has a sensory epithelium over the basilar membrane.
10) The sensory epithelium is in contact with gelatinous tectorial membrane.
11) The sensory cells have sensory hair on their free end so also called hair cells. In between the rows of hair cells are present supporting cells.
12) Hair cells have long step microvilli called stereocilia on the apical surfaces.
13) Above these stereocilia, is a jelly like membrane called tectorial membrane. This organ act as a transductor, converting sound vibrations into nerve impulses.
14) The inner ear also contains a complex system called vestibular apparatus, located above the cochlea.
15) The vestibular apparatus is composed of three semi-circular canals and the otolith (macula is the sensory part of saccule and utricle).
16) Each semi-circular canal lies in a different plane at right angles to each other.
17) The membranous canals are suspended in the perilymph of the bony canals.
18) The base of canals is swollen and is called ampulla, which contains a projecting ridge called crista ampullaris which has hair cells.
19) The saccule and utricle contain a projecting ridge called macula. The crista and macula are the specific receptors of the vestibular apparatus responsible for maintenance of balance of the body and posture.
Functions :-
1) The vestibule sits between and connects the cochlea and semicircular canals and helps to maintain equilibrium.
2) Inner ear contains organs of the senses of hearing.
