Osmosis in Potato Cylinders

Osmosis in Potato Cylinders

Aim: Trying to find the average sugar concentration in the potato

cylinder cells.

I will use potatoes for my experiment because they are convenient and

shows fast results in osmosis.

[IMAGE]The diagram to the right shows a basic plant cell, however, the

difference between this diagram and the potato cells I will be using

is that the potato will not be green as it does not need chlorophyll.

The cell membranes in a potato cylinder are partially permeable; this

means that only particles that are the right size can diffuse through,

basically if the particle is too big it will not fit. Osmosis occurs

when there is a higher concentration of particles on one side of the

cell membrane than on the other. This will lead to the water particles

diffusing from an area of higher concentration to an area of lower

concentration.

[IMAGE]The diagram to the right shows a partially permeable membrane.

There is a higher concentration of water on the left side of the

membrane. This means that the diffusion will cause the water particles

to move from the left side to right side of the membrane.

Variables:

The variable that I will keep constant is the length of my potato

cylinders which will be kept at 4 cm. I will keep it the same length

so as to avoid a greater or less surface area. I will also keep the

volume of solution and the length of time the same to ensure reliable

results

The variables that I will change are the concentrations of my sugar

solution.

Finally my resultant variable will be the length changed of the potato

cylinders.

Prediction: I will make three predictions for this experiment, they

are as follows:

1. When the potato cylinder is placed in a solution with a high

concentration of sugar, the potato cylinder will decrease in size

due to the water particles diffusing into the sugar solution.