Biology Experiment

Biology Experiment

Hypothesis

I predict that the potatoes in the solution with high sugar

concentration will increase in mass the most, the potatoes in the

water with no sugar will lose the most mass.

Osmosis is the movement of water from a high concentration to a low

concentration across a particularly permeable membrane. The water can

move between the potato and the solution but the sugar can’t because

the molecules are too big to pass through the membrane. The water

will move between the solution and the potato. If the net movement of

water is from the potato then the potato will decrease in mass, it

will also become flaccid. If the net movement of water is from the

solution then the potato will increase in mass and become turgid.

This is because the vacuole pushes against the cell wall.

When the sugar concentration is 0% the potato will gain mass because

there is a higher concentration of sugar inside the potato. The

potato will weigh more because the vacuole has gained water and become

turgid. It will be harder and won’t be floppy

When the concentration is 12.5% the potato’s mass will not change much

because the sugar concentration inside the potato is approximately

12.5%.the cells vacuole will stay almost the same as it was when it

was put into the sugar solution.

When the concentration is 20% the potato’s mass will decrease because

the net movement will be from the potato to the sugar solution. The

stronger sugar concentration is outside of the potato so the vacuole

will become smaller and the potato will be flaccid, so it will be

floppy and soft.

Preliminary Work

I carried out a preliminary experiment to find out which potato size

will be best for the experiment, the best size will need to provide

more accurate and relevant results.

The apparatus that I used for the experiment was;

· Potatoes slices x 20

· Scalpel