Question

Two adjacent cells A and B are being studied. Cell A has an OP of 10 atm and TP of 6 atm. Cell B has an OP of 10 atm and TP of 4 atm.
Movement of water will occur from.
(a) Cell A to cell B
(b) Cell B to cell A
(c) No movement of water
(d) Cannot be determined

Answer 1

Hint: The movement of solute and water depend upon the concentration gradient from higher to lower concentration and in some cases from lower to higher concentration. Transportation takes place by different modes like diffusion, osmosis, imbibition, plasmolysis, etc.

Complete answer:
OP represents osmotic pressure which is defined as the pressure developed in the osmotic system due to entry of water, while TP represents turgor pressure which is the pressure exerted by a cell wall over protoplast.
The diffusion pressure deficit represented by OP minus TP. Water will move from a system of low DPD to high DPD.
In case of A DPD = 10 - 6 =4 atm.
In case of B DPD = 10 - 4= 6 atm.
The movement of water will take place from A to B.

Additional Information:
  Turgor pressure is important for the plant due to its significance like:
Turgor pressure keeps the cells and their organelles fully enlarged which help plants to grow and survive. It helps in cell enlargement, which causes stretching in leaves and stem. It provides mechanical support for non-woody tissue. It regulates the opening and closing of stomata. It controls the movement of touching me not plant by loss or gain of cell turgor and in case of loss of turgidity, the wilting of leaves and drooping of shoots occurs.
So, the correct answer is ‘Cell A to cell B’.

Note: Definition of turgor pressure and wall pressure is same but normally wall pressure is equal and opposite and opposite to turgor pressure, except when the cell becomes flaccid. When the cell becomes fully turgid, turgor pressure becomes equal to wall pressure.