Porous potatoes - Osmosis

[cassiemhotmailcom]

I was hoping someone would help me with this.

Okay so you have an experiment where you use potato cores with NaCl solutions of different concentraions ( 0%, 0.5%, 1%, 2%, 5%, 10%)

What is likely to happen to the potato cells and what occurred within the cell?
What would be the control measures for this experiment?
What is the variable?
What are two limitations related to this activity?

thanks guys!

[mcar]

As far as I know, 0.9% NaCl is isotonic.

[JorgeLobo]

give us your hypothesis and experimental design

[BlackCat]

i've done that experimet short time ago... when the potatoes cores are putted in that solutions it will loose or get water or doesn't loose or gain water. So the objective of this experiment is to find the hydric potencial of the potato. When the concentration of the solution is lower than the potato, water gets out from the potatoe. when the concentation of the solution is higher, water get into the potato. when the concentrations are the same, it neither looses or gain water.
I don't know how was your experiment but in mine, we controled the weight of the potatoes cores. If wheight increases so the potatoe has gained water, decreased when it looses water, and mantain if no water is traded.

Just a note to mcar: as far as i known 0.9% NaCl is isotonic to hemacies...not every tissues, and is not aplicable to the potatoe for example...

[plasmodesmata11]

I think it may be described backwards above... If there is more solute in the solution than in the potato (hypertonic), water will move out of the potato, and if there is less solute in the solution than in the potato (hypotonic), water will move into the potato. I have done this with starch, glucose, and dialysis tubing before...

[BlackCat]

yes... you're right plasmodesmata 11. I always think about the movement of solutes and not the water...
Sorry my mistake

[wintersong]

hi!...
i understand that water moves from the potatoe and into the high soloute concentration via osmosis, but is there any salt in the potatoe? if so does it move in or out via diffusion or facilitated diffusion?
thanks!

[BlackCat]

Hi
Potatoes are not made exclusivety of water of course. Solutes moves via facilitated diffusion through chanels oriented by gradient of concentration.