Question

Which of these is a unit of measurement of water potential/osmotic pressure?
A. Watts
B. Joule
C. Pascal
D. Litre

Answer 1

Hint:Because of osmosis, gravity, mechanical pressure, and matrix effects such as capillary action, water potential is the ability of water to pass from one region to another (which is caused by surface tension). The minimum pressure to be applied to a solution to stop the inward movement of its pure solvent through a semipermeable membrane is osmotic pressure.

Complete answer:
Osmosis is the passage of a liquid to a higher concentration of a solution from a lower concentration of solution across a semipermeable membrane (from high solvent concentration to lower concentration of solvent). Usually, the solvent is water in biological systems, but osmosis can happen in other liquids and even gases.
Osmosis occurs when a selectively permeable membrane separates two solutions containing different solute concentrations. Solvent molecules migrate preferentially from the low-concentration solution to the higher solute concentration solution via the membrane. Until balance is achieved, the transfer of solvent molecules will continue. Osmosis may be opposed by increasing the pressure in the region of high solute concentration with respect to that in the low solute concentration region.
The force needed to prevent the passage of water (or any other high-liquidity solution) through a selectively permeable membrane into a higher-concentration solution per unit area, or pressure, is equal to the osmotic pressure of the solution.
A significant factor influencing cells is osmotic pressure. Now, let's see how we calculate osmotic pressure.
osmotic Pressure (\[\pi \]) Equation: \[\pi =MRT\]
M is the dissolved species (units of mol/L) molar concentration.
R -ideal constant gas (0.08206 L atm mol-1 K-1, or other values depending on the pressure units).
T — Kelvin temperature.
\[\pi \] -The osmotic pressure and its measurement unit is the pascal.
So, From the above discussion, we have seen what is osmotic pressure and its unit of measurement. A unit of measurement according to the SI system is Pascal.

So, the correct answer is option C- Pascal.

Note: In plants, animals, and even in human beings, osmosis has an important role to play. Osmosis in animal cells helps to absorb water from the intestines into the blood.
Water absorption from the soil is due to osmosis. Therefore, the plant roots have a greater concentration than the soil, so the water flows through the roots.
The plants' guard cells are also affected by osmosis. The guard cells swell up and the stomata open when the plant cells are filled with water.