Question

What is the pressure potential for the following:

i) Hypertonic cell

ii) Hypotonic cell

iii) Plasmolysed cell

Answer 1

Hypertonic cell:

1. A solution that has a higher concentration of solutes as compared to the cell is referred to as a hypertonic solution.
2. As the solute concentration rises, the pressure required to prevent water from entering the cell also rises.
3. Thus in a hypertonic cell, the pressure potential is increased.
4. This will cause fluid to move out of the cell.

Hypotonic cell:

1. A solution having a lower concentration of solutes than the cell is called a hypotonic solution.
2. As the solute concentration falls, the pressure required to prevent water from entering the cell also falls.
3. Thus in a hypotonic cell, the pressure potential is decreased.
4. This causes fluid to move inside the cell.

Plasmolysed cell:

1. Plasmolysis is the process of contraction or shrinkage of the protoplasm of a plant cell.
2. It is caused due to the loss of water in the cell.
3. The pressure potential in plasmolyzed cells is almost zero.
4. When water is drawn through an open system, such as a plant's xylem vessel, negative pressure potentials develop.
5. Plant cells subjected to hyperosmotic stress frequently exhibit plasmolysis as a reaction.
6. The live protoplast violently separates from the cell wall as a result of the loss of turgor.
7. The vacuole is primarily responsible for the plasmolytic process.
8. Living plant cells exhibit plasmolysis, which is reversible (deplasmolysis).