A vacuole is an organelle found in plant,animal, and even single celled protists, but not in bacteria.
A vacuole is used by cells in order to store water and some wastes.
In plants the vacuole is very large, and in animals they are small and there may be more than one vacuole.
Some protist have a contractile vacuole that regulates the amount of water found in the protist.
The structure of vacuoles is rather simple. It is contructed of a membrane that surrounds a mass of fluid. In that fluid are nutrients or waste products.
Most of a plant cell's volume will depend on the material found in vacuoles.
Those vacuoles gain and reduce water depending on how much water is available to the plant. A drooping plant has lost a lot of its normal water and the vacuoles are shrinking.
Why is a vacuole important?
Vacuoles may serve a wide variety of functions in a cell, and their importance depends on what role they take up within the cell. Typically, their task include,