Trachea the trachea. The trachea is no more than 4mm diameter during the first year of life, expanding to its adult diameter by late childhood. The trachea is more mobile and of more variable length, deeper, and smaller in children. The trachea is lined with a layer of pseudostratified ciliated columnar epithelium. The epithelium contains goblet cells, which are glandular, modified simple columnar epithelial cells that produce mucins, the main component of mucus. Mucus helps to moisten and protect the airways. Mucus lines the ciliated cells of the trachea to trap inhaled foreign particles that the cilia then waft upward toward
History of beliefs about the human body about what he proposed as the discovery of the clitoris, stated that, "like a penis, "if you touch it, you will find it rendered a little harder and oblong to such a degree that it shows itself as a sort of male member." (There was much debate on the actual discovery of the clitoris between male European scientists and many claimed to have described it first: by dissecting the human body and writing down what was observed these European scientists could claim in their idea of the body that they had discovered or created new knowledge.) This one-sex model was