There are five primary tastes in humans: sweet, sour, bitter, salty, and umami. Each taste has its own receptor type that responds only to that taste. Tastants enter the body and are dissolved in saliva. Taste cells are located within taste buds, which are found on three of the four types of papillae in the mouth.
Regarding olfaction, there are many thousands of odorants, but humans detect only about 10,000. Like taste receptors, olfactory receptors are each responsive to only one odorant. Odorants dissolve in nasal mucosa, where they excite their corresponding olfactory sensory cells. When these cells detect an odorant, they send their signals to the main olfactory bulb and then to other locations in the brain, including the olfactory cortex.
neuron with two processes from the cell body, typically in opposite directions
in the olfactory bulb, one of the two neural clusters that receives signals from one type of olfactory receptor
sense of taste
airborne molecule that stimulates an olfactory receptor
sense of smell
neural structure in the vertebrate brain that receives signals from olfactory receptors
specialized tissue in the nasal cavity where olfactory receptors are located
dendrite of a specialized neuron
one of the small bump-like projections from the tongue
substance released by an animal that can affect the physiology or behavior of other animals
food molecule that stimulates gustatory receptors
clusters of taste cells
one of the five basic tastes, which is described as “savory” and which may be largely the taste of L-glutamate