Exercise 2: The Five Sense, Taste

The Sense of Taste

By: rebeca, margarita, claudia, annika

One theory was provided as to how our sense of taste can identify different tastes. For example, how is it possible that we are to differentiate between a piece of candy versus lemonade? The theory states that different taste buds include a possible way of separating bitter, sweet, sour, and salty. However, a recent experimentation has found a new discovery and has added a fifth sensation to the grouped taste buds. It is known to be called Umami. Umami was found out by a Japanese scientist and the taste is found in many of the savory content of seaweed. Glutamic acid was isolated as a fifth tastebud. 

The bitter taste in our mouth is known to be present due to  TAS2R38 (our taste receptors in type 2) couple to a G-protein. The genetics of the dominance of bitter taste can be studied by two substances: phyenylthiocarbamide (PTC) nd 6-n-propylthioracil (PROP) which determines the strength of bitterness due to a human's genetics. Sweetness is due to G protein taste receptors which are coupled with G protein gustducin. Moreover, there must be two sweet receptors to be activated in order for the brain to recognize a sweet sensation. When sodium ions are received in the mouth, this is particularly why we taste a saltiness in the mouth. Lastly, sourness is due to hydrogen ions.

Taste is a part of the central nervous system. Taste buds are also known as receptor cells which allows one to be able to distinguish a specific taste. Inside each taste bud is a gustatory receptor cell where approximately 50 receptor cells make up one taste bud. Inside each gustatory receptor cell includes something called gustatory hairs which reach through to the outside of the tongue by the taste pore. These hairs interact with a mixture of saliva and molecules, allowing humans to be able to taste. Then a stimulus activates a gustatory impulse. Next, the receptor cells synapse with neurons and transmit these signals to the section of the brain which interpret the specific taste.