Biologically, what differentiates a bad smell from a good smell?

Question

I guess pretty much the title. Does bad smells trigger some kind of different olfactory receptors than good smells, or is it really just our brains with “personal preferences”?

In: Biology

Answer 1

Bad smells are very often tied to things that could be harmful to our health, such as bacteria or mold. These are things that could have killed ancient ancestors. The ones who found these smells bad and avoided them were more likely to pass on their genetics, and thus, their children found these smells to be bad as well, and so on.