Trachea act as a resonator to amplify sound. In some birds, the tracheal rings are complete, and may even be ossified. In amphibians, the trachea is normally extremely short, and leads directly into the lungs, without clear primary bronchi. A longer trachea is, however, found in some long-necked salamanders, and in caecilians. While there are irregular cartilagenous nodules on the amphibian trachea, these do not form the rings found in amniotes. The only vertebrates to have lungs, but no trachea, are the lungfish and the "Polypterus", in which the lungs arise directly from the pharynx. The word "trachea" is used to
History of beliefs about the human body body has in the world. All cultural ideals of the body in the early modern period deal with deficiencies and disorders within a body, commonly told through a male ideal. Ideas of the body in the early modern period form the history of how bodies should be and how to correct the body when something has gone wrong. Therefore, early modern conceptions of the body were not biological as there was not a restrictive biological view of the human body as established by modern science. Conceptions of the body are primarily either eastern, based in China and involving practices such