a thin piece of wood or other rigid material used to immobilize a fractured or dislocated bone, or to maintain any part of the body in a fixed position. 2. one of a number of thin strips of wood woven together to make a chair seat, basket, etc.
If you take a close look at epithelial cells using a microscope, you will see them tightly packed together. This helps make a protective barrier for our bodies. There are also some special door-like connections between each epithelial cell called gap junctions. The gap junctions are where the cells exchange nutrients.
1 The pleura is a two layered sac that holds the lungs and separates them from the chest wall, diaphragm, and heart. 2  Pleurisy results from an inflammation of this sac.  The pleura that lines the inside of the chest is called the parietal pleura. The pleura that covers the lungs is called the visceral pleura. If you are healthy, the pleura is separated by a thin layer of fluid. This lets the lungs expand and contract easily during breathing.