Q. What is Osmotic Pressure?

Ans.

Important characteristic of a cell is 'osmosis'. You would recall reading about osmosis in the Applied Physiology Course in Unit 8. In this section, let us learn more about cell and how it behaves when placed in water or any other solution. Do you remember the structure of bacteria? Yes, bacterial cell is contained by a cell membrane, which allows water to pass in and out of the cell. Active bacteria contain an excess of 80% wat

In the Figure, you can see a simple representation of the process of osmosis, where a membrane separates the solute molecules. Transfer of a liquid solvent through a semipermeable membrane that does not allow dissolved solids (solutes) to pass is osmosis.

'fie tendency to equalize water concentration inside and outside the cell in this case causes partial dehydration, where the cell shrinks and is called plasmolysis '. Instead, if the bacterial cell is placed in distilled water, the water enters the cell and causes it to burst. This is known as plasmoptysis'. The tendency of cell membrane to allow water to pass from inside to outside or vice versa, is there to maintain an equilibrium between the cell contents and its fluid surroundings. As the hydrostatic pressure causes osmosis, it is known as osmotic pressure.