Taste and Smell Flashcards
what are the 5 flavors
salt, sweet, umami, sour, butter
what tastes savory
amino acids
what tastes bitter
simple ions and complex organic molecules
what tastes sweet
sugars/ carbohydrates, proteins, artificial sweeteners
what tastes sour
acid
parts of the throat
pharynx, epiglottis
anatomy hierarchy of tounge
papillae, taste buds, taste cell
how many taste buds are in 1 papillae
papillae (visible to naked eye) have 1-100’s of taste buds (microscopic)
how many taste cells in 1 taste bud
50-150 taste cells
taste pore
pore on surface of the tongue that connects to taste cells
gustatory afferent axons
transmit taste information from the tongue and other areas of the oral cavity to the brain via cranail nerves for higher level processing
2 types of taste cells
broadly tuned and taste selective cells
broadly tuned cells
respond to 2 or more taste stimuli
taste selective cells
detects only 1 taste stimuli
taste cells vs axon response
follow same firing pattern as taste cells
which tastes use ion channels
salty (Na+) and sour (H+)
which tastes use g protein coupled receptors
sweet, savory, bitter
ion channel mechanism
Na+ into the cell, increase conc, depolarize cell, Ca2+ channels influx (voltage gated ion channel), vesicle fuse and transmitter release
H+ into cell AND binds to K+ channel to stop K+ from leaving -> depolarization and action potential
g coupled protein receptors depolarization mechanism
g proteins stimulate enzyme phospholipase C which produces IP3, IP3 opens Na+ channels, depolarization
g coupled protein receptors transmitter release mechanism
IP3 triggers release of Ca2+ from intracellular storage sites, activates ATP permeable channel, ATP transmitter
bitter receptors
-25 types
-2 T2R proteins
sweet receptors
- only 1 type
-2 T1R proteins
savory receptors
- only 1 type
-2 T1R proteins
cranial nerve VII
facial nerve; info from anterior 2/3 of tongue