why do plant cell has large sized vacuole

Dear Student

Plant cells have a single, large sized vacuole as compared to animals which have many small sized vacuoles. The main reason behind this fact are as follows: 

Storage: Plants form the base of the food chain. They are capable of converting inorganic matter to organic matter. To store these inorganic ions they are provided with the large vacuoles. Moreover, plants can not move from one place to another. So, it is very easy for a plant to be able to store extra nutrients when they are around for use later when nutrients may not be available.

 Growth: Plant cells grow by swelling. They are provided with a rigid cell wall. To make this wall expand, plant cells fill their vacuoles to exert pressure from inside.

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