Question

Plasmolysis in a plant cell is defined as

विकल्प

• break down (lysis ) of plasma membrane in hypotonic medium

• shrinkage of cytoplasm in hypertonic medium

• shrinkage of nucleoplasm

• none of them

Answer 1

shrinkage of cytoplasm in hypertonic medium

Explanation - 

When a cell is placed in a hypertonic solution i.e., a solution in which the concentration of water molecules outside the cell is lesser than the concentration of water molecules inside the cell, the cell will lose water by the process of osmosis (exosmosis). Although water crosses the cell membrane in both directions, but more water leaves the cell than enters resulting in the shrinkage of the cell cytoplasm. This phenomenon of shrinkage of the cell cytoplasm, when put in a hypertonic solution, is called plasmolysis.