Gustation Flashcards
what is gustatory sense?
taste; chemoreceptors that are stimulated by various chemicals
what is a taste bud?
small clusters of receptor cells and supporting cells scattered about tongue and other surfaces of oral cavity
what is tongue papillae?
contain taste buds
what are the types of tongue papillae?
vallate, fungiform, and foliate
what is vallate papillae?
dome-shaped; contains 100s of taste buds
what is fungiform papillae?
mushroom-shaped; contain few taste buds
what is foliate papillae?
ridges on sides of tongue; only contain taste buds in childhood
what is filiform papillae?
long, thin cylinders scattered across tongue; devoid of taste buds; detect food texture and temperature
what are the 5 taste sensations?
sweet = simple sugars (glucose, fructose)
sour = hydrogen ions (citric acid)
salty = metal ions (sodium and potassium)
bitter = nitrogen-containing compounds
umami (savory) = glutamate or other amino acids
transduction of salty and sour tastes in a gustatory cell
salty and sour = open ion channels which depolarize cell and allow release of neurotransmitter
bitter, sweet, and umami = G-protein activation which leads to depolarization by closing Potassium leak channels
what are the cranial nerves function in the gustatory pathway?
carry taste stimuli from tongue to CNS
what is the thalamus’ function in the gustatory pathway?
send impulses to primary gustatory cortex in parietal lobe
what is taste signals role in gustatory pathway?
provides emotional reactions to taste; integrates with limbic, visual, and olfactory systems
