S. Namuuntulga Tuesday 14.20 Essays - Perception, Nervous System

S. Namuuntulga Tuesday 14.20 The nose sense of smell and taste The nose is a organ used for breathing and smelling that is found in the center of the face above the mouth. At the end of the nose there is a pair of nostrils, these allow you to breathe in air and exhale it. At the end of the nostrils comes the nasal cavity. Going farther up, the cavities divide into 3 shelf-like bones called nasal concha e or turbinates these warm inhaled air. The outside of the nose consists of a elastic tissue called cartilage. The human nose is in fact the main organ of smell as well as taste. We can recognise thousands of different smells, and we are able to detect odours even in infinitesimal quantities. The sense of smell is very closely related to the sense of taste. Sometimes the odor makes us think what the food will taste like, if we did not have the sense of smell the sense of taste would be greatly affected, you would have the basic tastes but nothing like you have now. Smell occurs in the olfactory, this is where nerve receptors lie, then passes through to the mouth causing most of the sensation of taste. Smell-sensitivity researchers have to be very careful about the odours they use in experiments, because a smell is not always a smell. Many odorous substances activate not only the olfactory system but also the somatosensory' system -the nerve endings in our noses which are sensitive to temperature, pain etc. This is why anosmics ' - patients who have completely lost their sense of smell - can still detect menthol, phenylethyl alcoh ol and many other substances. The sense of smell triggers a fight or flight response that helps survival. Our ability to taste is another scientific feat on its own. We are able to tell great tasting food from unpalatable ones of the millions of taste cells called "gustatory cells" that are clustered within taste buds of the tongue, lining of your throat and roof of the mouth. That we're born with around 10,000 taste buds. When we chew food or drink soup, these substances combine with our saliva and release molecules that stimulate these gustatory cells. Like the nose, there are specific taste cells responsible for detecting and identifying a taste quality. Your gustatory cells send signals to your brain to interpret the taste or group of tastes that are being detected. There are five basic taste qualities: sweet, sour, salty, bitter and savory or "umami". Umami is brought by glutamate, which can be found naturally in protein-rich foods or artificially in form our monosodium glutamate, also known as " vetsin ". Taste, along with smell determines flavors of food or other sub stances. In conclusion, nose is in fact the main organ of smell as well as taste. Both senses - smell and taste are part of our body's chemosensory system, or simply referred to as the "chemical senses". This is because taste and smell both work by making sense of the chemicals surrounding us - the substances that combine to create a dish or the millions of molecules that comprise different odors. References http://www.encyclopedia.com