Cell A has osmotic potential of -18 bars and pressure potential of 8 bars, whereas, cell B has osmotic potential of -14 bars and pressure potential 2 bars. The direction of flow of water will be

Options

A. from cell B to cell A
B. from cell A to B
C. no flow of water
D. in both the directions

Answer

A

Explanation

The water potential is the chemical potential of the water, which is equivalent to diffusion pressure deficit with negative sign. Therefore, water potential (`Psi_(A)`) of cell A is
`Psi_(A)=Psi_(S)+Psi_(P)=-20+5=-15` bars
`Psi_(B)=Psi_(S)+Psi_(P)=18+2=-2` bars
Since, water moves from higher water potential to lower potential, the flow of water will be from cell B (-2 bars) to cell A (-15 bars).