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
The World Is What It Is The World Is What It Is The World Is What It Is: The Authorized Biography of V. S. Naipaul is a biography of the Nobel Prize-winning author V. S. Naipaul by Patrick French. It was published in 2008 (by Picador in the UK and Knopf in the USA). The title is a quotation from Naipaul's book "A Bend in the River". "The world is what it is; men who are nothing, who allow themselves to become nothing, have no place in it." French deals with Naipaul's family background and his life from his birth in 1932 until his second marriage