Potato Osmosis Lab

Osmosis Lab

Introduction:
In order for cells to interact with their environment, molecules must be able to move through the cell membrane. Movement within the cell occurs by diffusion. Molecules move through the cell membrane by osmosis. Diffusion is the movement of molecules from a region of higher concentration to a region of lower concentration. This happens because of random molecular motion. Molecules move around randomly until there is an even mixture throughout cell and mixture. The overall effect is that molecules move down a concentration gradient from a region of high concentration to a region of low concentration which is passive transport. Osmosis is the movement of molecules down a concentration gradient and at the same time
If there is a concentration gradient across the membrane, water will move across the membrane down the concentration gradient while the salt cannot. If there is more salt and less water inside a cell than outside, water will flow into the cell from the surrounding environment. This process is called osmosis. When the environment outside a cell has a lower concentration of dissolved molecules than inside the cell, the solution is hypotonic, and water will move from the solution into the cell. If the surrounding solution has a higher concentration of dissolved molecules than the cell, the solution is hypertonic. In that case, water will move from the cell out into the surrounding solution. An isotonic solution is when the concentration of dissolved molecules is the same inside and outside the cell, and there is no net movement of water across the membrane. When cells are placed in a hypertonic solution, water flows out of them and they shrivel up. When cells are placed in a hypotonic solution, water flows into them. If the cell does not have a cell wall, it will burst in a hypotonic solution. The purpose of this lab is to observe the effect of isotonic, hypotonic, and
Osmosis was clearly shown since the potato cylinders decreased or increased at different concentrations of sucrose. The results supported my hypothesis because for the 0.0 sucrose concentration the average percent change in mass was 16.9%. For the 0.2 concentration the percent change was 3.59%. For the 0.4 concentration the percent change was -15.3%. For the 0.6 concentration the percent change was -27.1%. For the 0.8 concentration the percent change was -23.2%. For the 1 concentration the percent change was -15.4%. The reason for the change in mass is the process of osmosis. When the sucrose concentration was 0, the cores gained weight because the concentration in the potato cells was different from the concentration outside, which was a hypertonic solution. When the sucrose concentration was 0.2, it was an isotonic solution, so there was no major difference in mass. When the concentrations of sucrose were higher (0.4, 0.6 and 0.8), the outside solution was hypotonic because there was a decrease in the potato