Any of the three loop-shaped membranous inner tubular parts of the semicircular canals that are about one-fourth the diameter of the corresponding outer bony canals, that communicate at each end with the utricle, and that have near one end an expanded ampulla containing an area of sensory epithelium [ http://dictionary.reference.com/browse/semicircular+duct ]
术语信息
- UMLS:C1323109 (ncithesaurus:Semicircular_Duct)
- FMA:61122
- EMAPA:32830
- MA:0000251
- NCIT:C33528
- SCTID:279833009
- VHOG:0000238
In gnathostomes, each membranous labyrinth has three semicircular ducts that connect with a chamber known as the utriculus (...); Gnathostome ears have a horizontal semicircular duct. This brings their complement to three semicircular ducts, a pattern retained throughout gnathostome evolution.[well established][VHOG]
Any of the three loop-shaped membranous inner tubular parts of the semicircular canals that are about one-fourth the diameter of the corresponding outer bony canals, that communicate at each end with the utricle, and that have near one end an expanded ampulla containing an area of sensory epithelium