Which plant is used for demonstrating plasmolysis in the laboratory?

When the cell (or tissue) is placed in ......... solution, there is no net flow of water towards the inside or outside.

In the process of osmosis,the volume of the solvent:

In the process of osmosis,which component acts as a semi-permeable membrane?

If a potted plant is surrounded by an overdose of urea around it,what will happen?

An onion peel was taken and
$(a)$ placed in salt solution for five minutes.
$(b)$ after that it was placed in distilled water.
When seen under the microscope,what would be observed in $(a)$ and $(b)$?