ears

consists of auricle (pinna) and auditory canal (acoustic meatus)

gather sound waves & funnel to auditory canal (the way the sound bounces off auricles allows brain to detect direction of sound)

produce cerumen (ear wax). Sound travels through the canal until meeting eardrum causing it to vibrate and the bones in middle ear to vibrate

• also known as tympanic cavity and has four openings...
• epitympanic recess
• oval window
• round window
• pharyngotympanic tube (auditory tube)

leads to mastoid process

connecting to inner ear

leads to temporal bone

leads to pharynx

• smallest bone in body connecting to each other in linear fashion
• malleus (hammer) attaches to eardrum and to...
• incus (anvil) attaching to stapes...
• stapes (stirrup) attaching to oval window sending vibrations into inner ear

also called labyrinth lying within temporal bone filled with fluid

connecting to oval window containing sensory epithelium called macula (has receptors called hair cells synapsing with vestibular nerve) detecting position of head changing in linear acceleration

three canals lying along a different plane with the crista ampullaris detecting rotational acceleration via hair cells

• Cochlea: forms spiraling chamber containing receptors for hearing arranged in rows of hair receptors detecting vibrations traveling through fluid in chamber (endolymph) and these hearing receptors are called organ of corti----as the hair cells detect vibrations, they send a signal to cochlear nerve joining vestibular nerve with impulse
• traveling to brain-->
• organ of corti-->
• hair cells detecting vibrations-->
• cochlear nerve-->
• vestibular nerve-->
• brain

• -Equilibrium information travels to the brain through the vestibular nerve to the brainstem and then to the cerebellum or to the reflex centers.--->equilibrium-->brain-->vestibular nerve-->brainstem-->cerebellum or reflex centers-Auditory information travels from cochlear nerve to brain stem to the thalamus and then to auditory cortex or from brainstem to auditory reflex center
• -->auditory-->
• cochlear nerve-->
• brain stem-->
• thalamus-->
• auditory cortex or brainstem-->
• auditory reflex center

• - smell & taste are sharp in newborns-
• children have more taste buds than adults-
• taste & smell declines around 40