Transport in Plants Question 14
14. Two cells A and B are contiguous. Cell A has osmotic pressure $10 atm$, turgor pressure $7 atm$ and diffusion pressure deficit $3 atm$. Cell $B$ has osmotic pressure $8 atm$, turgor pressure $3 atm$ and diffusion pressure deficit $5 atm$. The result will
[2007]
(a) no movement of water
(b) equilibrium between the two
(c) movement of water from cell A to B.
(d) movement of water from cell $B$ to $A$.
Show Answer
Answer : c
Hints & Solutions
(c) Movement of water will be from low DPD to high DPD i.e from A to B The term diffusion pressure deficit (DPD) was coined by B.S Meyer in 1938. Originally DPD was described as suction pressure by Renner (1915). It is a reduction in the diffusion pressure of water in solution or cell over its pure state due to the presence of solutes in it and forces opposing diffusion. Diffusion pressure deficit (DPD) is the amount by which two solutions differ in their diffusion pressure. It is defined as the amount by which the diffusion pressure of water or solvent in a solution is lower than that of pure water or solvent. It allows easy absorption of water due to diffusion pressure gradient.