In young dividing cells, there are many small vesicles which fuse one or more large vesicle called vacuoles. The vacuoles are separated from the cytoplasm by a single vacuoles membrane called the tonoplast. The functions carried out by lysosomes in animals cells are performed by large vacuoles in plants. Vacuoles are filled with cell sap which is acidic in nature and play of role in maintaining pressure with in the cell. Plant cell use their vacuoles for transporting and storing nutrients such as salts, sugar, organic acids, small quantities of soluble proteins, pigments and waste products. The vacuoles regulate the flow of water and solute of the cells such as osmotic regulation, and help in digestion and recycling of certain materials with in the cell, and help in breakdown of organelles such as mitochondria and plastids.
The water soluble pigments called the anthocyanin pigments, which are found in vacuoles, impart color to the flower petals to attract insects for pollination’s. Some vacuoles participate in defense mechanisms. Plants cannot move to avoid being eaten by herbivores, so sometimes toxic metabolites are stored as a means of defense that are released from vacuoles of the plants when they are eaten or being damaged. You have thus seen that the vacuoles is a remarkably versatile organelles of the plant cell interior and the plants cell use their vacuoles in a variety of ways of which space filling and storage of the most prominent ones.