Question

The osmotic pressure of the cell is measured by
A) Plasmolysis method
B) Osmometer
C) Molar concentration of the cell sap
D) Deplasmolysis

Answer 1

Hint: Osmotic pressure is the pressure created by water moving across a membrane due to osmosis. When more water moves across the membrane, the osmotic pressure increases. Osmosis is the movement of water from a solution of higher water potential to a solution of lower water potential across a semipermeable membrane that separates the two solutions.

Complete answer: Plasmolysis method is based on the phenomenon of plasmolysis where the cells of the tissue which must be examined are placed in salt solutions of various concentrations. The solution which has the same osmotic pressure as that of the cell asp causes no change in the cell. The solution that causes a slight shrinkage in the cell away from the cell wall is taken as isotonic or isosmotic with the cell sap. Osmometer is used for measuring osmotic pressure, osmotic concentration, or strength.
-The molar concentration of the cell sap: Molarity or molar concentration is the amount of substance in a given volume of solution.
-Deplasmolysis is also called cytolysis. It is a reverse process of plasmolysis. It is a process of plasmolyzed cells returning to its initial state.
Thus, the correct option is B (Osmometer)
Additional information:
There are several different techniques in osmometry:
-Vapour pressure osmometers: determine the concentration of osmotically active particles because of which the vapour pressure of the solution is reduced.
-Membrane osmometers measure the osmotic pressure of a solution separated from pure solvent by a semipermeable membrane.
-Freezing point depression osmometers: determine the osmotic strength of a solution as the osmotically active compounds depress the freezing point of a solution.

Note: Osmometers are used to determine the total concentration of dissolved salts and sugars in blood or urine samples. It is also used in determining the molecular weight of unknown compounds and polymers.