Question

We conducted an experiment in which we put beetroot in 4 different solutions (CaCl2,NaCl, CaCl2 with NaCl, and water)

Can you with use of scientific websites and their resources explain how this experiment relates to selective permeability of cell membrane ( for your explanation because scientific sites do not need to contain beetroot you can find other things but with relation to selective permeability of cell membrane and solutions).

Use scientific papers and include their references!!!!!!!! Please

Answer 1

Osmotic pressure is directly proportional to von`t Hoff factor as we can see by the following equation-

$\pi$ = i M R T

where $\pi$ is osmotic pressure

i is Von`t Hoff factor

M is molarity

R is gas constant

T is temperature

Now if CaCl2 is considered it breaks up ideally into three ions: Ca2+, Cl-, Cl-. In this case, the ideal van't Hoff factor equals three and NaCl breaks up ideally into 2 ions-Na+, Cl- ions. Hence its Von`t Hoff factor is 2. That certainly means that osmotic pressure exerted by Cacl2 is more than NaCl, hence Cacl2 solution is more hypertonic to NaCl solution.

Now when the beetroot is placed in NaCl solution which is hypertonic to the cell of beetroot as NaCl is a salt solution then water from the cells will go towards the hypertonic solution and the cells will shrink.

Similarly when the beetroot is placed in a solution containing Cacl2, again a hypertonic solution, same will happen i.e water from the cells will go towards the hypertonic solution and the cells will shrink.

Finally, when the beetroot is placed in CaCl2 with NaCl solution it will be more hypertonic as two salt solution are present, making the water molecules move from the beetroot cells to the salt solution and thus the cells will shrink.

When the beetroot is placed in the water which is isotonic to the solution the movement of water from the water to the beetroot and the movement of water from the beetroot towards the water is equal and thus there will be no shrinkage or swelling, the cells of the beetroot will remain as it is.