Investigation of Osmosis

Essay by Musefan101High School, 10th gradeA+, May 2004

download word file, 6 pages 4.0

Downloaded 38 times

Aim:

I am going to investigate osmosis in plant cells by seeing how potato chips change weight in different strength sugar solutions.

Introduction:

Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration.

The tiny holes in the membrane allow water molecules to pass through. But the large solute molecules are too big to pass through the partially permeable membrane.

Prediction:

In this experiment I plan to measure the weight of potato chips before and after being put in sugar solutions with different concentrations of water.

I predict that in pure water the potato chips swell because water enters their cells by osmosis, where as in rich sugar solution the potato chips shrink because water leaves their cells due to osmosis. This is because in pure water there is a very high concentration, which is a lot more than the concentration of water in the potato cells so water passes through the partially permeable membrane; this causes the potato cells to swell because they are becoming saturated.

The potato cells shrink in rich sugar solution because there is a low concentration of water molecules in the sugar solution, so the water molecules are acting as if they are trying to dilute the sugar solution, so as to even up the concentration on either side of the membrane.

Plan:

In this experiment I plan to investigate the affect of osmosis in potato cells before and after being put into different concentrations of sugar solution.

I will do this in the following way:

Cut 5 chips all the same size from the same potato or potato from the same bag.

Weigh each chip

Put the chips in the different sugar solutions in each test...