Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells

Investigating the Effect of Sugar Solution on the Weight and Size of Potato Cells

Aim:

To investigate whether the different concentration of sugar solution

will affect the weight and size of the potato cells.

General background information:

Osmosis is defined as the movement of water or any other solution's

molecules from an area in which they are highly concentrated to a

region in which they are less concentrated. This movement must take

place across a partially permeable membrane such as a cell wall, which

lets smaller molecules (E.g. water) through but does not allow larger

solute molecules to pass through. The molecules will continue to

diffuse until the area in which the molecules are found to reach a

state of equilibrium, meaning that the molecules are equally

distributed throughout the cell, with no area having a higher or lower

concentration than any other hence equal.

Hypothesis/prediction:

For this particular investigation I believe that the lower the

concentration of the sugar solution in the test tube the mass of the

potato will be greater and the longer the potato cells will be. This

is because the water molecules pass from a low concentration to a high

concentration, (in the potato chip). Therefore, the chips in low

concentrations will gain mass and have a greater length height than in

higher concentrations such as 1molar of sugar solution. If there is no

gain or loss in height or mass then these will be the isotonic points

of the potato cells. The isotonic point is where the cells are not

increasing or decreasing in size and is known to be in a state of

equilibrium.

Apparatus:

1. Potato

2. Standard sugar solution (1molar)

3. Wash bottle

4. Test tubes and test - tube rack

5. Cork borer-size (4mm diameter)

6. Scalpel

7. Ruler

8. Wooden Board

9. Measuring Cylinder-size (250cm3)

10. Top-pan Balance

11. Paper Towels

Variables:

To enable fair test certain aspects of the experiment will have to be