Question

The speed of water absorption will be greater if

• A. the difference between osmotic pressure of soil water and that of xylem vessels is always less
• B. there is no difference between osmotic pressure of soil water and that of xylem vessels
• C. the difference between osmotic pressure of soil water and that of xylem vessels is always more
• D. the water potential of soil water is always less than that of xylem vessels

Answer 1

The correct option is C the difference between osmotic pressure of soil water and that of xylem vessels is always more

Osmotic pressure refers to the minimum pressure which is required to be applied to the solution to prevent the entry of solvent molecules through the semi-permeable membrane. A greater difference between osmotic pressures of soil water and that of xylem vessels would indirectly mean a greater difference between the solute concentration and water potential. The speed of water absorption will be greater if the difference between osmotic pressure of soil water and that of xylem vessels is always more.