Tongue map

Different sections of the tongue having different tastes is a misconceptionhttps://en.wikipedia.org/wiki/Tongue_map
It starts with a German researcher Dirk P. Hänig. His diagram was meant to show that taste sensitivity is at the edges of tongue rather than its center. And also the bitter threshold sensitivity is lower at the back while the sweet threshold is lower at the front, but these differences are minute.
Threshold sensitivity just says how much of the chemical you need to feel any kind of taste, so this finding doesn't tell you that different areas of the tongue will feel certain tastes more intensely, it only says you need more sugar at the back of your tongue to recognize that it is sugar but this difference is tiny.
A Harvard made English translation suggests that different sections of the tongue taste exactly one of the basic tastes, which original papers clearly wasn't saying. 
Different taste cells can detect different cells, but one taste bud contains around 100 of these cells so one taste bud detects all of the tastes and we have thousands of taste buds.
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