Question

If vacuole prevent cell bursting then how plasmosis happen

Answer 1

A vacuole is simply a chamber surrounded by a membrane, which keeps the cytosol from being exposed to the contents inside.
they prevent from cell bursting

Plasmolysis is when plant cells lose water after being placed in a solution that has a higher concentration of solutes than the cell does. This is known as a hypertonic solution. Water flows out of the cells and into the surrounding fluid due to osmosis. This causes the protoplasm, all the material on the inside of the cell, to shrink away from the cell wall. Severe water loss that leads to the collapse of the cell wall can result in cell death. Since osmosis is a process that requires no energy on the part of the cell and cannot be controlled, cells cannot stop plasmolysis from taking place.

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