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Encyclopedia > Auditory vesicle
Auditory vesicle
Embryo between eighteen and twenty-one days.
Section through hind-brain and auditory vesicles of an embryo more advanced than that of Fig. 898.
Gray's subject #228 1030
Precursor auditory pit
Dorlands/Elsevier v_07/12855397

The mouth of the auditory pit is then closed, and thus a shut sac, the auditory vesicle (or otic vesicle[1]), is formed; from it the epithelial lining of the membranous labyrinth is derived. Image File history File links Gray40. ... This article or section is in need of attention from an expert on the subject. ... The first rudiment of the internal ear appears shortly after that of the eye, in the form of a patch of thickened ectoderm, the auditory plate, over the region of the hind-brain. ... Elseviers logo. ... The first rudiment of the internal ear appears shortly after that of the eye, in the form of a patch of thickened ectoderm, the auditory plate, over the region of the hind-brain. ...


The vesicle becomes pear-shaped, and the neck of the flask is obliterated.


From the vesicle certain diverticula are given off which form the various parts of the membranous labyrinth. Diverticula are outpouchings of the intestinal wall. ...


One from the middle part forms the ductus and saccus endolymphaticus, another from the anterior end gradually elongates, and, forming a tube coiled on itself, becomes the cochlear duct, the vestibular extremity of which is subsequently constricted to form the canalis reuniens.


Three others appear as disk-like evaginations on the surface of the vesicle; the central parts of the walls of the disks coalesce and disappear, while the peripheral portions persist to form the semicircular ducts; of these the superior is the first and the lateral the last to be completed.


The central part of the vesicle represents the membranous vestibule, and is subdivided by a constriction into a smaller ventral part, the saccule, and a larger dorsal and posterior part, the utricle. Categories: Stub ... Otolith organ Utricle is also a fruit type, found in beet and dock. ...


This subdivision is effected by a fold which extends deeply into the proximal part of the ductus endolymphaticus, with the result that the utricle and saccule ultimately communicate with each other by means of a Y-shaped canal.


The saccule opens into the cochlear duct, through the canalis reuniens, and the semicircular ducts communicate with the utricle.


Additional images

References

  1. ^ Embryology at UNC ear-005b

 
 

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