1、智课网 TOEFL备考资料托福阅读背景知识之味觉系统摘要： 有关托福阅读背景知识的内容有很多，了解这些托福阅读北京对我们阅读答题的准确率和速度提升很有帮助，托福阅读的背景知识包含很多：自然科学类、人文科学类、互联网类等等，而本文来为大家介绍一些有关味觉系统的相关内容介绍。托福 阅读背景知识之味觉系统:Take a deep breath. Taste anything? Actually， your lungs may. Because scientists have discovered that the same receptors that exist on the tongue to
2、taste bitter substances are also found on the smooth muscle of the lungs.Researchers were studying the receptors on smooth lung muscles that regulate contraction and relaxation of theairways. Thats when they made the discoverywhich was so unexpected that the researchers themselves were skeptical.Fin
3、ally， they became convinced that the receptors were really there， though not clustered in taste buds as they are on the tongue. The scientists then exposed human and mouse airways to various bitter compounds to gauge the effects.Many toxic compounds are bitter,so the researchers expected the lung mu
4、scle to tense up and contractto compel the breather to move away from whatever was bitter and perhaps toxic. But， in a second surprise， bitter compounds relaxed and opened airways better than any existing asthma drug. The study is in the journal Nature Medicine. Deepak Deshpande et al.， “Bitter tast
5、e receptors on airway smooth muscle bronchodilate by localized calcium signaling and reverse obstruction”Researchers will continue to search for the role of the receptors. Meanwhile， the work represents a surprising new lead in the search for drugs to treat asthma， emphysema or chronic bronchitis.Cynthia Graber以上就是有关 托福阅读 北京知识味觉系统的相关内容介绍，希望对大家的 托福口语 考试会有一定的帮助，托福阅读有关其他类的托福阅读背景知识，我们在其他类的学习过程中会陆续为大家介绍，希望能够扩充大家的托福阅读知识面，提高大家的托福阅读成绩。
