Vacuole
Structure: Vacuoles are fluid-filled sacs inside of a cell.Function: Vacuoles main purpose is to store materials and maintain internal pressure for a plant. Vacuoles are special structures and serve a particular function. The vacuoles are most prominent in plant cells. When seen through microscopes, they appear to be large, round, and are very clear. They vacuoles store a fluid called sap. Sap is made up mostly of water, salts, and sugars. The vacuole may contain so much liquid that it takes up 90% of the cell’s total volume. Vacuoles that are this large will push the cytoplasm against the cell wall. If a plant cell remains full of liquid, it will maintain its certain type of pressure, called turgor pressure. Turgor pressure could be compared to air against the inside of a balloon. If a vacuole does not have enough turgor pressure it will collapse or wilt. The vacuole, therefore, keeps the plant from wilting and stores its salt.
