Osmosis Experiment Lab Report

The Independent Research Project conducted in this article is designed to test the effect of magnesium sulfate concentrations on the mass of chicken liver. To determine this effect, the experiment will conclude the difference of mass after osmosis has occurred.

Osmosis is the process of water diffusing through a partially permeable cell membrane. Osmosis occurs when one side of the membrane has a different concentration of water, and the water molecules move through the membrane to a less concentrated area until equilibrium occurs. Equilibrium is the outcome of osmosis, when equal concentration of water occurs on both sides of the cell membrane. There are three tonicities, or ways in which osmosis can travel. A hypotonic tonicity is when the concentration of water is higher inside the cell membrane, which causes the cell(s) to lose in mass from water diffusing out of the membrane. A hypertonic tonicity is the opposite, where the water concentration inside the cell membrane is lower than the concentration of the solution outside of the membrane, causing the cell(s) to gain in mass and the solution outside of the cell membrane to diffuse water. Isotonic tonicity is when both sides of the cell membrane have the same concentration of water, and diffusion will not occur.

It is important to know the difference of cell exterior between plant and animal cells because it affects osmosis.

Plant cells have a stronger membrane because they have a cell wall and cell membrane. The cell wall can become turgid when too much water is entering the cell, making it the wall hard enough to stop the intake of water entering into the cell. This is specific to plant cells because it does not allow the excess water to burst the cell. Animal cells only have a cell membrane as an exterior to solutions, which creates a less protective barrier. When excess water comes in from a hypotonic solution, there is no cell wall to become turgid, and the cell will eventually

burst.
The effect of osmosis varies in different tissues and solutions. Muscle tissue will not have a hypotonic change in mass. This is most likely because muscle tissue bought at a store is already treated with preservative solutions that contain salt, so this type of tissue has already gone through osmosis. A sodium chloride solution will not work because the salt molecules are so small, that they will also enter the cell membrane and cause a hypotonic mass. Magnesium sulfate solution is a better solution to use because this salt has larger particles that will not go into the cell membrane. Glucose solution is not a valid solution because the change in mass yielded inconsistent results. Liver tissue is the best tissue to experiment on because it is not processed, and if it is processed, it is not processed with salt.
The experiment will look at the effect of magnesium sulfate concentration on change in mass. This can be done by putting liver tissue in a magnesium sulfate solution and allowing it to sit for eight hours, so osmosis can occur.