Question

During absorption of water by roots, the water potential of cell sap is lower than that of
(a) Pure water and soil solution
(b) Neither pure water nor soil solution
(c) Pure water but higher than of soil solution
(d) Soil solution but higher than that of pure water

Answer 1

Hint: Water potential is the amount of P.E. in water and is additionally the difference between the potential during a given water sample and pure water. High water potential means the amount of free solute in the given solution is less compared to the solution at a lower water potential.

Complete step by step answer:
During absorption, there's a degree gradient between cell sap and soil solution. At the time of absorption, the concentration of water within the cell is a smaller amount compared to the soil solution, so at now, the water potential of cell sap goes to be but that of pure water and also that of the soil solution.
So the correct answer is 'Pure water and soil pollution'.

Additional Information: The behaviour of cells in concern to water movement depends on the encircling solution. If the external solution is more dilute than the cytoplasm, it's said to be hypotonic and thus the cell tends to swell in hypotonic solutions. water is hypotonic as compared to a cell.
When cells are placed in water, water moves from outside the cell to the within. A cell may contain many solutes so it's considered hypertonic as compared to water which is hypotonic So during this case when a cell is placed in water, water moves from outside of the cell to the within resulting in swelling of the cell.
Water, when boiled to vapour then condensed back to liquid form during a separate container, is known as ‘distilled water.’ The impurities present within the original water which does not get boiled below or near the boiling point of water are separated within the first container. Thus, water is free from impurities and solutes and should be a form of purified water.

Note: Water potential can also be defined as a measure of how freely water molecules can move during a selected environment or system. It's measured in its unit, that's kilopascals (kPa) and is represented by the Greek letter Psi. Water potential isn't positive but it'll have a maximum value of zero, which is that of pure water at air pressure.