Factors Affecting Osmosis

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Factors Affecting Osmosis

The aim of this experiment is to investigate the factors affecting

osmosis. I have chosen to investigate the effect varying concentration

of sucrose solution has on the amount of osmotic activity between the

sucrose solution and a plant cell. The plant cell I have chosen to use

is a potato tuber from which I plan to cut potato chips of equal

length which I will place in test tubes filled with varying

concentrations at equal volumes of sucrose solution. After a set

amount of time I will remove the potato chips and record the change in

length.

BACKGORUND KNOWLEDGE

High water potential is a solution which has a high concentration of

water and a low concentration of solute (e.g. sugar, sucrose or salt)

or no solute at all. Therefore it can either be a very dilute solution

of something like sucrose or pure water, however in each case there is

a lot of water. Whereas low water potential is the opposite of high

water potential being a solution of low concentration of water and

high concentration of solute (sugar, sucrose or salt). Hence it can be

a concentrated solution of something like sucrose, however in this

case there is much less water.

When to solutions one of high water potential and one of low water

potential are divided by a semi-permeable membrane water molecules

will move from the solution of high water potential through the

partially permeable membrane to the solution of low water potential.

This will continue until both sides have reached a state of

equilibrium or isotonic point, which is when both solutions wither

side of the partially permeable membrane have equal water potential

neither having higher or lower potential, they are said to be

isotonic. When this occurs there is no net movement of water across

the membrane only random diffusion of particles.

What I have discussed in the previous paragraph is the process of

osmosis, however in short osmosis is defined as the net movement of

water molecules from a high water potential through a partially

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