Bitter Sweet Synphony

In today's lab we tested various carbohydrates ranging from monosaccharides to polysaccharides. As my group and I tasted these carbohydrates we noticed that the more complex the sugar, the worse it tasted. This result was somewhat expected. Since we know that cellulose, a polysaccharide found in plant cell walls, tastes bitter and fructose, a monosaccharide used in fruit, tastes sweet, we can infer that with the more rings found in a carbohydrate, the more bitter it will taste. But what allows us to taste sweetness? What allows us to taste bitterness? Nervous cells located on the tongue allow us to taste both sweetness and bitterness. The taste we associate with sweetness is made from sugar, which is made of glucose and fructose. The reaction starts when the proteins on the tongue are altered, causing the nervous cells in the tongue to send a message to the brain. This message is the perception of taste. The same process occurs when we eat something sour.