词条 | tongue |
释义 | tongue anatomy in most vertebrates, an organ, capable of various muscular movements, located on the floor of the mouth. In some animals (e.g., frogs) it is elongated and adapted to capturing insect prey. The tongues of certain reptiles function primarily as sensory organs, whereas cats and some other mammals use their tongues as instruments for grooming and cleaning. In mammals the tongue aids in creating negative pressure within the oral cavity that enables sucking, and it is an important accessory organ in chewing and swallowing; it is also a major bearer of taste buds and, in humans, an aid to speech. ![]() An important function of the tongue is taste sensation, which is derived from taste receptor cells located in clusters within taste buds on the surface of the tongue. In humans there may be anywhere from 50 to 150 taste receptor cells within an individual taste bud. Taste buds are innervated by nerves that respond to chemicals from food in solution, thereby providing the sensation of taste. There are five fundamental taste sensations: salty, sweet, sour (acid), bitter, and umami, which represents the taste of amino acids (amino acid). Each receptor cell is sensitive to a particular taste—for example, responding only to salt or only to umami. The total flavour of a food comes from the combination of taste, smell, touch, texture or consistency, and temperature sensations. Small taste buds situated on the tongue's top surface transmit these flavour sensations to the nervous system. Among the disorders to which the tongue is subject are cancer, leukoplakia (white patches), fungus infection, congenital defects, and a variety of symptoms caused by disease elsewhere in the body. Surgical removal of this organ makes speech and swallowing difficult. |
随便看 |
|
百科全书收录100133条中英文百科知识,基本涵盖了大多数领域的百科知识,是一部内容开放、自由的电子版百科全书。