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
Theology of the Body original design for human sexuality and thus the dignity of the human person, how it was distorted through sin, and how it has been restored and renewed through the redemption of Jesus Christ; and Catholic teachings about the sacramentality of marriage. The central thesis of John Paul's Theology of the Body, according to author Christopher West, is that "the body, and it alone, is capable of making visible what is invisible: the spiritual and the divine. It was created to transfer into the visible reality of the world, the mystery hidden since time immemorial in God, and thus to be