Exam 19: Development of the Ears

Branchio-oto-renal syndrome,characterized by kidney and hearing defects,is due to mutation of which gene?

The prosensory region in the saccule forms which structure(s)?

The cristae detect which modality?

Which muscle(s)are associated with the ear ossicles?

Would mutation in genes that encode cytoskeletal components such as ACTIN,ESPSIN,and HARMONIN be expected to result in sensorineural or conductive hearing loss?

Researchers have genetically inactivated transcription factors that are expressed in the developing ear of mice.This has shown that various transcription factors are necessary for the development of different regions of the inner ear.Pax2 function is required for development of which region of the inner ear?

The inner ear arises from which structure?

Development of the sensory regions of the inner ear involves the formation of hair cells and supporting cells by the process of lateral inhibition controlled by Notch signaling.How would overexpression of the transcription factors Hes1 and 5,which are modulated by Notch signaling,be expected to affect the number of hair cells or supporting cells?

Which signaling pathway controls the orientation and arrangement of the stereocilia on the inner hair cells?

Hereditary deafness can result from mutations in many genes.Which gene is mutated most frequently in nonsyndromic congenital deafness?

Microtia/anotia can be associated with other birth defects as a component of a syndrome.What percentage of children with microtia/anotia would be expected to have additional congenital abnormalities?

The number of hair and supporting cells in the inner ear is determined by which signaling pathway?