Eli5: What happens to our tastebuds when we eat something sour or spicy, how does it let our brain know

Question

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In: 4

Answer 1

You have lots of specialized nerves all ready to send a signal to the brain. To send the signal, something has to switch them on. This is done by specialized surfaces on them that have a very specific shape, sort of like a jigsaw puzzle. When something with the correct shape happens to hit that surface, it activates and the nerve sends that signal off to the brain. You then taste whatever has been detected, some combination of salty, sweet, umami, bitter, or sour.