Both taste and smell are considered chemosensations: ways we sense chemicals. The “chemicals” we’re sensing are molecules that float through the air (smell) or come from the things we put in our mouths (taste). Taste and smell are closely related—they combine to produce our perception of flavor, and they rely on receptors (neurons) that actually come into contact with the environment outside our body. The rest of our sensory neurons are protected from the world by a layer of skin or some other tissue. Because they’re protected, there is no process for regeneration, and once a neuron in your eyeball or inner ear dies, it doesn’t get replaced. But olfactory receptors and taste neurons both take a lot of abuse and new cells are born throughout our lives to replace the ones that die.
This chapter was created by Shawna Ratanpal, Rowan Sexton, Kori Skrypek, Brock Sorensen, Samantha Strubing, Barbora Tomancova, Savannah Vasek, Alex Wallace, Jacob Weckwerth, Maria Xiong, Peter Yong, and Grace Zellner.