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.
Together, the lungsâ tissue surface is almost 40 times greater than the bodyâs outer surface, making the lungs (together) one of the largest organs in the body. Each lung houses a bronchial tree, which gets its name from the intricate network of air passages that supply the lungs with air.