Answer :
It's a part of human body survival instincts,Specialized taThe purpose of our ability to distinguish tastes is survival," says Trey Wilson, DDS, a New York City–based dentist. "Taste buds tell your brain whether or not to swallow what's already in your mouth." According to Dr. Bartoshuk, infants are born loving sweet and hating bitter, because natural sugar—not the sugar in, say, a processed candy bar, as we think of it today is brain fuel, while bitter is the sensory cue for poison. "The taste system evolved to protect a baby who hasn't learned anything about what is good and bad for himself yet," she explains. Additionally, sodium is a mineral that's essential for making our muscles and nerves work, thus many people's cravings for salty snacks.ste receptors inside the taste buds allow us to distinguish sweet, salty, sour and bitter things
the mouth is used to taste food, so taste buds are covering the inside of the mouth