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In the alveoli, oxygen from the air is absorbed into the blood. 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 pleural membrane lines the lungs. It is a thin visceral layer that has some fluid between the layer and the lungs. If there is no fluid in this layer, and the layer become â¦ s dry there is a condition called pleurisy which can happen as a result of friction produced.3 people found this useful.he outer pleura is attached to the chest wall and is known as the Parietal pleura; the inner one is attached to the lu â¦ ng and other visceral tissues and is known as the Visceral pleura. In between the two is a thin space known as the pleural cavity or pleural space.