The perception of taste is remarkably complex, not only on the tongue but in organs throughout the body.
The idea that specific tastes are confined to certain areas of the tongue is a myth that “persists in the collective consciousness despite decades of research debunking it.” Also wrong: the notion that taste is limited to the mouth.
There’s lots of stuff textbooks get wrong simply because there’s no easy way to explain how it ACTUALLY works at an appropriate grade level.
For example, wings and lift. We’re told that the curved surface of a wing causes air to move faster on one side of the wing than the other and this generates lift.
No, that’s not how it works, but you can be forgiven for thinking that since that’s all most people are taught.
https://www.scientificamerican.com/video/no-one-can-explain-why-planes-stay-in-the-air/