Trachea annular ligaments of trachea. The epiglottis closes the opening to the larynx during swallowing. The trachea develops in the second month of development. It is lined with an epithelium that has goblet cells which produce protective mucins (see "Respiratory epithelium"). An inflammatory condition, also involving the larynx and bronchi, called croup can result in a barking cough. A tracheotomy is often performed for ventilation in surgical operations where needed. Intubation is also carried out for the same reason by the inserting of a tube into the trachea. From 2008, operations have experimentally transplanted a windpipe grown by stem cells, and
History of beliefs about the human body the senses to identify what has gone wrong. The Ebers Papyrus refers to many god-like and spiritual infestations of the body that could not be explained at the time. Despite the explanations for maladies by spiritual rational, the interventions described to investigate and see the body were distinctly disconnected for the spirit or life force of the body and was principally about what could be seen or touched. Descriptions of the exact placement of the heart within the body, the circulation of blood are in no doubt accurate as Egyptians practiced embalming their dead by removal of organs and placement