Re: Is one tastebud (sweet, bitter, salt or sour) more sensitive than the other

Aloha, Emily
     Thank you for submitting such an interesting question.  In fact, I had 
to go back to several of my anatomy/physiology texts to be sure of the 
answer.  That means I was able to learn something, too.
     According to one of the current college-level textbooks (_Fundamentals 
of Anatomy and Physiology_ by Frederic Martini, 3rd. edition), tastebuds do 
differ in their sensitivity to stimuli.  In general, the tastebuds that 
respond to 'bad' tastes (bitter and sour) do so at a much lower level of 
substances than do the tastebuds that respond to 'good tastes' (sweet and 
salty).  This makes sense evolutionarily, since we would have wanted to 
avoid the bad tasting-stuff (sometimes dangerous, too) and take in the 
good-tasting stuff (probably for the energy and nutrients).  For example, 
compounds called acids (which taste sour) can damage the cells that make up 
the lining of the mouth...and many bitter substances are also toxic, or 
poisonous, to the human.
     Also, did you know that each person has a slightly different 
sensitivity to tastes?  These differences are probably inherited from your 
biological parents.  Some people are extremely sensitive to a chemical 
called 'phenylthiourea'....some people can't taste it at all.
     Lastly, your ability to taste will change with age.  By the time 
you are about 50 years old,  you may begin to lose lots of your ability to 
taste.  If you have anyone in your family around this age, they may talk 
about how bland their food tastes.  That same food may taste very salty, 
spicy, or sweet to you now.  This could be an interesting experiment for 
you to try, don't you think?
     Thanks again for such an interesting question.

Dian Dooley