Special Sense (Ear) Flashcards
What are the 3 anatomical regions of the ear?
external ear middle ear (tympanic cavity) inner ear (labyrinth)
What are the external and middle ears mainly involved in?
reception and transmission of sound waves to inner ear, where sound waves are converted to electrical impulses and conveyed to brain
What does the inner ear contain?
organ of balance
External Ear
What does the external ear include? (2)
- auricle
- external acoustic meatus
External Ear
What is the auricle?
has cartilaginous core covered by thin skin
External Ear
What does the auricle carry?
some contours that collect sound and transfer it to external acoustic meatus
External Ear
What is the lobule?
inferior part of auricle, and its cartilage is replaced by connective tissue
External Ear
What is the external acoustic meatus?
S-shaped long canal extending from auricle to tympanic membrane (ear drum)
External Ear
Is the external acoustic meatus bony or cartilaginous?
lateral ⅓ is cartilaginous
medial ⅔ is bony
External Ear
What does the thin skin covering the external acoustic meatus contain?
ceruminous glands (modified sweat glands) that secrete cerumen (ear wax) that slows growth of microorganisms in external acoustic meatus, and reduces risk of infection
Middle Ear (Tympanic Cavity)
What is the middle ear?
irregular cubic space contained within petrous part of temporal bone
Middle Ear (Tympanic Cavity)
What is the middle ear lined by?
mucous membrane that is continuous with that of nasopharynx
Middle Ear (Tympanic Cavity)
What are the 3 ossicles?
malleus, incus, and stapes
Middle Ear (Tympanic Cavity)
What do the 3 ossicles do?
amplify and convey sound from tympanic membrane to inner ear
Middle Ear (Tympanic Cavity)
How are ossicles jointed to each other?
by synovial joints
Middle Ear (Tympanic Cavity)
What are the 2 small skeletal muscles in the middle ear?
What do they do?
tensor tympani and stapedius
dampen sound