main olfactory epithelium

G_(olf)

odorant receptor

bitter

sweet

sour

salty

umami

gustducin

amiloride-sensitive Na⁺ channel

rod

cone

rhodopsin

opsin

retinal

chromophore

transducin

cGMP phosphodiesterase

cGMP-gated ion channel

rhodopsin kinase

arrestin

guanylate cyclase

hair cell

stereocilia

tip link

nociceptor

capsaicin receptor (VR1)

980