The Ear Flashcards
Which bone houses the vestibule-cochlear apparatus
The petrosal temporal bone
Which two cranial nerves pass the internal aucostic meatus
The vestibulocochlaer and facial nerve
What is the ear the organ of
Hearing and equilibrium
What membrane separates the middle ear from the external ear
The tympanic membrane
Which structure joins the nasopharynx to the middle ear
The auditory tube
How does the external ear deal with the hearing process
The auricle and external aucostic meatus capture sound waves and direct them to the tympanic membrane
How does the internal ear process hearing
The semi-circular canals and the cochlea convert mechanical signals to electric signals which are transmitted to the brain via the vestbulocochlear nerve
What is the main sensory innervation of the external ear
Largely by the greater auricular and auriculotemporal nerves
What is the function of the external ear
Supportive function
- catches and funnels the sound into the external aucoustic meatus and then to the tympanic membrane and inner ear
What kind of epithelium is the external aucousti meatus lined with
Stratified squamous epithelium
What are cermunious glands
The modified sweat glands that secrete ear wax
What is the function of the ear wax and the hairs in the external aucostic meatus
To keep forgein bodes away from the tympanic membrane
How is the tympanic membrane held in the temporal bone
By a fibrocatilganeous ring
When looking in an otoscope of the tympanic membrane what is a key feature of a heathy ear and why is this?
A cone of light ( caused from light from the otoscope) this is health as it means there is no fluid accumulation or pathology
Which are the two small muslces oresent in the tympanic cavity ( middle ear)
The stapedius and the tensor tympani