ch. 16 - smell and taste

chemoreceptors

specialized sensory cells that detect specific chemical molecules and convert them into biological signals. Respond to chemicals in aqueous solution

olfactory epithelium

covers the superior nasal conchae and contains olfactory sensory neurons

bipolar neurons

olfactory receptor neurons in the olfactory epithelium. a single dendrite that extends to the epithelial surface and an axon that travels to the olfactory bulb. contains apical cilia detecting odorants and imitation electrical signals

tongue papillae

tiny raised structures on the surface of the tongue. receptor organs

fungiform papillae

help perceive taste and flavor

gustatory epithelial cels

taste cells containing gustatory hairs acting as receptors.

3 types:

• releases serotonin

• lack synaptic vesicles

• one releases atp as neurotransmitters

basal epithelial cells

dynamic stem cells that divide every 7-10 days

sweet taste

sugars, saccharin, alcohol, some amino acids, some lead salts

sour

H+ in solution

salty

metal ions

bitter

alkaloids such as quinine and nicotine and aspirin

umami

amino acids glutamate and aspartate