GUIDE WITH COMPLETE SOLUTION!!
1.External ear: consists of the auricle and external acoustic canal (meatu
2.Auricle: shaped to funnel sound waves into the external acoustic canal
so that sounds can be detected. The auricle is the part of the ear that
can be seen externally; composed of elastic cartilage covered with thin
skin
3.Lobule: earlobe, lacks supporting cartilage
4.Rim: helix
5.external acoustic meatus: the tunnel between the auricle and tympanic
mem- brane; composed of elastic cartilage near the auricle and
becomes a cylinder through the temporal bone; canal is lined with skin
containing hairs and glands that secrete cerumen
6.Cerumen: ear wax; serves to trap foreign materials
7.Tympanic membrane: eardrum; thin membrane of connective tissue
whose vi- bration transmits sound energy to the middle ear
8.Middle ear: also called tympanic cavity; an air-filled chamber
containing the three smallest bones in the body, which are known as
the ossicles
9.Ossicles: malleus (hammer), incus (anvil), stapes (stirrup)
10.Malleus: receives the vibrations from the eardrum and transfers
them along through the incus, then finally the stapes, which conveys
them to the inner ear
11.Inner ear: composed of the bony and membranous labyrinths filled
with fluid; bony labyrinth system is divided into three sections: the
vestibule, semicircular canals, and cochlea
12.Vestibule: connects to three semicircular canals, which house
receptors to provide the body's equilibrium and balance system
13.Semicircular canals: contains equilibrium receptors, which cause
action poten- tials in response to different types of motion (head
movements or rotation) and are sent through the vestibular portion of
CN VIII; all filled with fluid
14.Vestibular sense: sense of balance and upright orientation
15.Stapedius: innervated by the facial nerve and connected to the
stapes; controls the amount of tension on the bone, allowing for
increased or decreased vibration to help control the intensity of sounds
16.Cochlea: a spiral, bony chamber containing the membranous
endolymph-filled cochlear duct
17.Organ of corti: housed in cochlea, terminates at the cochlear nerve;
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