Why a Chest Tube is Placed. A chest tube is placed for a variety of reasons. One reason, as you mentioned, is to help the lung re-inflate when someone has a collapsed lung, also known as a pneumothorax. In that circumstance, a chest tube is inserted along the side of the ribs to allow the lung to reinflate.
A. Osmosis is the passive movement of water from an area high in water concentration, across a semi-permeable membrane, to an area low in water concentration.
passive transport, the movement of small molecules across the membrane of a cell by diffusion. Passive transport occurs when the chemicals outside a cell become concentrated and start moving into the cell, changing the intracellular equilibrium. Passive transport is essential to various processes of metabolism, such as the intake of digestive products by the cells lining the intestines.