CH.YBW.Sen.C03.Final.q
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3 Sense of Taste Gustation, the sense of taste, is conducted by chemoreceptors that
respond to chemicals dissolved in watery solution in our mouths. Gustation is important because it provides information about the quality of the food and liquid that we consume. Most important, it helps us determine whether the items we place in our mouths should be swallowed or rejected. In fact, the word taste comes from the Latin word taxare, which means “to feel,” “touch,” or “judge,” which suggests that taste originally meant to test by touching. LOCATION OF TASTE RECEPTORS
The receptor organs for gustation are called taste buds, which are structures composed of specialized epithelial cells. Taste buds are found in the mouth, with most of them located on the superior (top) surface of the tongue. However, a few taste buds are also found in the pharynx (throat), soft palate, and epiglottis. As we age, these nonlingual (non-tongue) taste buds decrease in number and importance. The tongue has epithelial folds and bumps called lingual papillae, peg-like projections that give the tongue a slightly rough feel (Figure 3.1). There are four types of lingual papillae on the human tongue; only three of these have taste buds. Foliate papillae are arranged as closely packed folds along the back edges of the tongue. They are well developed in children, but are much less prominent and numerous in adults. In fact, most of these taste buds degenerate by the time a person is 2 or 3 years old. Fungiform papillae are mushroom-shaped structures. They are the only
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