In this Article. In this Article. A solitary pulmonary nodule (SPN) is a single abnormality in the lung that is smaller than 3 cm in diameter. Generally, a pulmonary nodule must grow to at least 1 cm in diameter before it can be seen on a chest X-ray.
Osmosis is the scientific process of transferring fluid between molecules. When molecules move in and out of a cell to achieve the same concentration of something, like salt, on both sides, then osmosis is happening.
exosmosis. 1  Biology. osmosis toward the outside of a cell or vessel. 2  Physical Chemistry. the flow of a substance from an area of greater concentration to one of lower concentration (opposed to endosmosis).