Term
| What is the first part of the ear to develop? |
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Definition
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Term
| What induces the growth of the otic placodes? |
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Definition
| notocord and paraxial mesoderm |
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Term
| The inner ear begins primordially as what? |
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Definition
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Term
| Otic placodes invaginate into the mesenchyme to form what? |
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Definition
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Term
| What are the primordia of the membranous labryrinth? |
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Definition
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Term
| What are the two parts of the otic vesicle? |
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Definition
Dorsal utricular part
Ventral saccular part |
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Term
| The dorsal utricular part of the otic vesicle becomes what? |
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Definition
| small endolymphatic duct, utricle, and semicircular ducts |
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Term
| The ventral saccular part of the otic vesicle becomes what? |
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Definition
| saccule and cochlear duct (contains spiral organ of corti) |
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Term
| What forms the semicircular ducts of the membranous labyrinth? |
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Definition
| 3 disc-like diverticula that grow out from utricular part of otic vesicle. These diverticula undergo apoptosis |
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Term
| What are localized dilations at the end of each semicircular duct called? |
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Definition
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Term
| What is the sensory organ for hearing? |
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Definition
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Term
| Vestibular ganglion and spiral ganglion arise from what? |
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Definition
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Term
| What in the inner ear develops first, the membranous or bony labryinth? |
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Definition
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Term
| How does the perilymphatic space form? |
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Definition
| vacuoles in the capsule coalesce between membranous and bony labryinth |
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Term
| Tubotympanic recess develops from what pouch? |
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Definition
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Term
| What two muscles arise from the middle ear? |
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Definition
| tensor tympani and stapedius |
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Term
| tensor tympani derives from what arch? |
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Definition
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Term
| stapedius derives from what arch? |
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Definition
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Term
| what does the external acoustic meatus develop from? |
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Definition
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Term
| What does the tympanic membrane derive from? |
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Definition
Ectoderm: 1st pharyngeal groove
Mesoderm: 1st and 2nd pharyngeal arches neural crest
Endoderm: tubotympanic recess first pharyngeal pouch |
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Term
| The auricle develops from what? |
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Definition
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Term
| auricular hillocks are derived from what? |
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Definition
| mesenchyme of first and second pharyngeal arches |
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Term
| What is the last part of the auricle to develop? |
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Definition
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Term
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Definition
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Term
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Definition
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Term
| What are auricular appendages? |
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Definition
| extra ear tissue growing from auricular hillocks |
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Term
| what are preauricular sinuses? |
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Definition
| little pits along the auricle |
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Term
| What is the significance of downslanted ears? |
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Definition
| Typically indicative of the presence of congenital defects |
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