Testing Diffusion Of Molecules Across The Cell Membrane

1406 Words Sep 10th, 2016 6 Pages
The purpose of this experiment was to test diffusion of molecules across the cell membrane to see which factor of time, concentration, and mass took effect of increase or decrease of diffusion over time. For the concentration experiment three different concentrations were made of the KMnO4. Three test tubes were filled with 4 ml of water. The first test tube had 1 ml of the 500 KmnO4 added to it. Then the second test tube had 1 ml from test tube one and 4 mL of water. For test tube 3, 1ml was taken from test tube two. Each concentration was placed into a dialysis tubing using the strings to tie off one end and the clamp to close off the other end. Before the dialysis tubing was placed in the beaker, 1ml of a sample was placed in a cuvette to blank the spectrophometer. Each stir plate was set on a low speed and the dialysis was hung in the water by a string. Every 5 minutes that passed a sample of 1 ml was taken and put into a cuvette. The cuvettes were placed in the spectrophometer to measure the absorbance of each solution. The measuremnts were then recorded in lab notebook. Once the measurements were documented, the average of absorbance and concentration was recorded.
For the temperature experiment, three hot/stir plates with a beacker set on top were set to 25 degrees Celsius, 37 degrees Celsius, and 50 degrees Celsius. Three dialysis tubing were filled with 2 ml of the 0.1 M KMno4 and were closed with a string on one end and a clamp on the other end. Before they were…
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