In computer networks and telecommunications, a dedicated line is a communications connection or other hardware resource dedicated to a certain application or use. This is different than a shared connection such as a telephone network or the Internet.
Carbon dioxide, a waste product of metabolism, travels from the blood to the alveoli, where it can be exhaled. Between the alveoli is a thin layer of cells called the interstitium, which contains blood vessels and cells that help support the alveoli. The lungs are covered by a thin tissue layer called the pleura. The same kind of thin tissue lines the inside of the chest cavity -- also called pleura. A thin layer of fluid acts as a lubricant allowing the lungs to slip smoothly as they expand and contract with each breath.
The lungs are a pair of spongy, air-filled organs located on either side of the chest (thorax). The trachea (windpipe) conducts inhaled air into the lungs through its tubular branches, called bronchi. The bronchi then divide into smaller and smaller branches (bronchioles), finally becoming microscopic. Lung cancer: Cancer may affect almost any part of the lung. 2  Most lung cancer is caused by smoking. 3  Tuberculosis: A slowly progressive pneumonia caused by the bacteria Mycobacterium tuberculosis. 4  Chronic cough, fever, weight loss, and night sweats are common symptoms of tuberculosis.