Chapter 15 summer (Smell and taste/hearing an equilibirum)

Taste transduction

Binding of a food chemical (tastant) depolarizes the cell membrane of the gustatory epithelial cell membrane, causing release of neurotransmitter, which activates the sensory neuron, causing an AP to the brain

Auricle/pinna (external ear)

funnels sound

External acoustic meatus/auditory canal (external ear)

contains earwax & hairs

Tympanic membrane/eardrum (external ear)

vibrates in response to sound.

External ear

funnels sound

Middle ear

transmit vibrations (hearing only)

Auditory ossicles (Middle ear)

Malleus, Incus, Stapes

Eustachian tube (Middle ear)

Equalizes pressure

Inner ear

detects sound and balance (hearing and equilibrium)

Vestibule (saccule/utricle) (inner ear

static balance (maculae)

Semicircular canals (inner ear)

rotational balance

Cochlea (inner ear)

hearing

Organ of Corti (cochlea)

contains hair cells that detect sound vibrations

Scala vestibuli (cochlea)

upper chamber beginning at oval window (contains perilymph)

Scala media (cochlea)

middle chamber (contains endolymph and organ of Corti)

Scala tympani (cochlea)

lower chamber ending at round window (contains perilymph)

Vestibular membrane (cochlear)

separates scala vestibuli and scala media

Basilar membrane (cochlea)

supports the organ of Corti

Inner hair cells (cochlea)

detect sound and send signals to brain

Outer hair cells (cochlea)

help with fine-tune hearing and protect inner hair cells

Vestibular apparatus

Equilibrium receptors in semicircular canals and vestibule

Crista ampullaris

sensory receptors that monitors dynamic equilibrium