(n) Increase in cAMľ
Extracellular fluid
Olfactory
Ciliurnof   "***
olfactory
neuron
molľciik'
Adenyl yl          Cation \
cyclase             channel\
Ga2+-activatedv CI" channel
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Olfactory,
Obrní of   rea'Pt0,;.
olfactory,
neuron
. I »doranl molecule
Calcium v channel
Ca2+-aetivafcid Cl~ channel
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Olfactory bulb Glomerulus
Forebrain
Olfactory tract (OT)
Olfactory nerve (ON) fibres Cribriform plate ' Olfactory epithelium
Olfactory receptor cell (ORC) Centrifugal fibre
Olfactory epithelium
Figure 13.7 Olfactory bulb, (a) The figure shows olfactory axons passing through the cribriform plate to end in glomeruli in the olfactory bulb, (b) Basic circuit of the mammalian olfactory bulb. Layers: ÉPL = external plexiform layer; GL = glomerular layer; GRL = granule cell layer; OT - olfactory tract; MCL = mitral cell layer. Cells: Gd = deep granule cell; Gs = superficial granule cell; M = mitral cell; PG = periglomerular cell; T = tufted    cell.    Inhibitory   cells    stippled.    Simplified    from
Taste bud
SENSORY PROCESSES
383
Taste bud eel] membrane
Depolarization
Cytoplasm
Depolarization
CAMP------*
Depolarization
id) Umami
Receptor,      ,Ghit«n-n,>L-
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Closed KH channel
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cAMP
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