Quote Originally Posted by The Ceej View Post
In elementary school science we learned a few things about the tongue and flavors.

We learned that all food falls among the only four flavors: Salty, sweet, sour, and bitter.

I can prove that wrong with this unanswerable question:
Describe the flavor of a white onion using only the terms, salty, sweet, sour, and bitter.
Flavours like that are comprised of bits and pieces of the other 'basic' flavours.
We also learned that each of these flavors has a designated part of the tongue that can only taste that flavor and nothing else.

I can prove that wrong with this unanswerable question:
Why is it that you can taste any food on any part of your tongue?
The tongue's quite small, so food gets spread across its surface relatively fast. You have to try really hard to apply a substance on only one area. And, as has been mentioned, most foods contain various flavours - so you'll get a reaction from just about any part of your tongue.

Here's a good test - wasabi, as most know, has a very strong flavour which creates quite a reaction. So, dab a spot of wasabi on the very front of your tongue. Observe the results. Once the taste has subsided, dab another spot of wasabi on the very back of your tongue. It'll barely register.

Much like the use of "punnet squares" to describe allele interactions, school science class does indeed simplify some things for the sake of simplicity and clarity. The basic principles are correct, though - in this case, the idea that the human tongue has different regions that are sensitive to different basic flavour types.