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
Traditional Chinese medicines derived from the human body Traditional Chinese medicines derived from the human body Li Shizhen's (1597) "Bencao gangmu", the classic materia medica of traditional Chinese medicine (TCM), included 35 human drugs, including organs, bodily fluids, and excreta. Crude drugs derived from the human body were commonplace in the early history of medicine. Some of these TCM human drug usages are familiar from alternative medicine, such as medicinal breast milk and urine therapy. Others are uncommon, such as the "mellified man", which was a foreign nostrum allegedly prepared from the mummy of a holy man who only ate honey during his last days and whose corpse