The organs of smell and taste

Chemical sensitivity presented in person by the organs of smell and taste. It certainly is the most ancient kind of sensitivity. It is chemical irritation primarily impacted the dawn of the cells on an unstable structure of living protoplasm. The higher animals chemical sensitivity have greatly improved. On the one hand, perceived in the substance of solutions that fall into the mouth (if it hits a solid body, which absolutely does not dissolve in saliva, we do not feel any taste). On the other hand, perceived chemical irritation from tiny particles of solid and liquid bodies (up to individual molecules)that are in the air and falling into the nose. Thus the sensitivity of the organ of smell is so great that it detects odorous substances where even the spectral analysis is powerless. Animals scent even thinner. Dog-Bloodhound until you can replace any art technical means. In this case, the organ of smell responds not only to a specific chemical component, and on the whole chord smells of the person sought.
Receptors of the body of taste are located mainly in the language and partly on the soft sky and back of the throat. No matter how varied taste sensations, they all come from mixing the 4 basic tastes. The tip of the tongue is sensitive to sweet tooth, a root of bitterness, lateral surface - to sour and salty. Mixed in different proportions, these four senses together with sensations food temperature, hardness and its area create a very rich variety of pleasant and unpleasant taste sensations. Here we are confronted with the phenomenon of synthesis, about which we'll speak. Nerve centers unite here some sensations in one indivisible unit.
It is clear why chemical sensitivity concentrated in the nose and the mouth. It is the nose and mouth, as already mentioned, the main ways by which substances from the outside world freely enter the body. The sense of smell and taste exactly the guards standing at the beginning of these ways, controlling, which substances enter the body.