It's OK To Be Smart: Hardwired for TasteThe brain is hardwired to recognize certain tastes, with particular regions shown to respond to bitter, sweet, salty and umami . Your Friday weird science moment is that sperm carry the umami receptor. Do ova taste savory? Oddly enough, the receptors that recognize these taste molecules aren’t limited to the mouth.
Sweet receptors are found in the intestine, which explains how our bodies respond so quickly with insulin after eating sugar. Bitter receptors in the large intestine may help recognize invaders and stimulate diarrhea.
(via Nature, subscription maybe required?)