1 In 1990, Barack Obama was elected as the first black president of the Harvard Law Review. 2  Obama, who graduated from HLS in 1991, would later represent Illinois in the U.S Senate, and in 2008 would become the 44 th President of the United States, and the first African-American president.
Most cancers in the lung are carcinomas-cancers of epithelial cells. The top pair of images shows the normal epithelium of the bronchi. This photomicrograph is greatly enlarged. The next three pairs of images show three successive stages of abnormal changes in the bronchial epithelium commonly found in smokers.
These bronchioles give rise to the air sacs in the lungs called the alveoli. The lungs are the largest organs in the lower respiratory tract. The lungs are suspended within the pleural cavity of the thorax. The pleurae are two thin membranes, one cell layer thick, which surrounds the lungs.he lower airways or lower respiratory tract includes the portion of the larynx below the vocal cords, trachea, bronchi and bronchioles. The lungs can be included in the lower respiratory tract or as separate entity and include the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.