Special Senses Smell and Taste Flashcards
odorant R
located on cilia in mucus layer
multiple odorants can activate each R
activation of R leads to production of cAMP which will open an ion gate allowing Na and Ca in
continued activation will lead to decrease sensitivity of ion channel to cAMP
activation of odorant R
each odorant activates different combinations of odorant R to produce its characteristic odor
higher concentrations of odorant will lead to activation of more R leading to change of perceived smell
TAAR R
activation does not lead to conscious awareness of an oder
produces physiologic endocrine response to pheromones
Granule cell body (smell)
found but not activated by olfactory cells
release GABA at junction w/ mitral and tufted cells
work to increase specificity of the message going to the olfactory cortex
mitral cells (smell)
travel to olfactory cortex
release glutamate to excite granule cell
tufted cells (smell)
travel to olfactory cortex
periglomerular (smell)
release GABA at junction w/ other glomeruli and inhibit the activity from those glomeruli
odorant producing the strongest stimulation will suppress the input from other glomeruli that were not strongly activated
smell transmission to the brain
olfactory R to glomerulus to mitral, tufted, and periglomerular cells to the lateral olfactory tract
entorhinal cortex
important in memory formation
olfactory input facilitates both memory formation and recall
piriform cortex
projects to lateral hypothalamus, controls appetite, can be controlled by olfaction
projects to medial orbitofrontal cortex to provide information that will be used to identify the flavor of foods, among other things
olfactory cortex
sends input back to the olfactory bulb to modify the R responses to odorants
sour taste
produced when hydrogen ion enters the taste bud via H ion channel
salty taste
produced when sodium or calcium ion enter the taste bud via Na or Ca channel
umami taste
R is metabotropic glutamate R activated by the AA glutamate
sweet and bitter taste
use second messenger systems to depolarize the cell, not directly related to the metabotropic R that detect the umami