BIOL 1208 Writing Assignment 2 Cover Sheet I certify that the writing in this assignment is my individual work and is my intellectual property It does not contain the ideas or writing of other individuals authors Author Date Lab Section Lab Partner Lap Topic Osmosis Lab Molecular Weight Affecting Hemolysis Time Introduction Hemolysis is the process of what happens to a red blood cell when placed in a hypotonic solution Because the solution is hypotonic the high concentration of water in the solution will move down its concentration gradient into the cell with the high concentration of solute The water rushes into the cell causing it to swell and burst Rate of diffusion hemolysis in this case depends on many factors such as complexity polarity size and shape because the cell s membrane is selectively permeable The experiment was carried out to determine if the size of glycol molecules determined by their molecular weight affected the rate of hemolysis in ovine red blood cells The null hypothesis states if you change the molecular weight of a glycol molecule it will not change the time it takes for hemolysis to occur The alternative hypothesis states that if you change the molecular weight of a glycol molecule then the time it takes hemolysis to occur will also change Specifically the time it takes hemolysis to occur will increase as the molecular weight and complexity of the glycol molecule increases Results The main trend in our results as shown in the graph below was the direct relationship between molecular weight of the glycol molecule and hemolysis time As the molecular weight of a glycol molecule increased the hemolysis time significantly increased as well Ethylene with the lowest molecular weight of 62 07 Daltons took 9 15 seconds to hemolyze While diethylene with a molecular weight of 106 12 Daltons 44 05 Daltons greater than ethylene took 16 55 seconds to hemolyze 7 4 seconds longer than ethylene Finally triethylene with a molecular weight of 150 17 Daltons 88 1 Daltons bigger than ethylene and 44 05 Daltons bigger than diethylene took 34 23 seconds to hemolyze 25 08 seconds longer than ethylene and 17 68 seconds longer than diethylene Hemolysis Time vs Different Glycols 40 35 30 25 20 15 10 5 0 i s e m T s i s y l o m e H Series1 Ethylene Diethylene Triethylene Different Glycols Figure 1 The rate of hemolysis in ovine red blood cells when placed in three different glycol solutions The bar graph demonstrates the relationship between molecular weight and hemolysis time as molecular weight increases hemolysis time increases Ethylene with the lowest molecular weight of 62 07 Daltons had an average hemolysis time of 9 15 seconds with a standard deviation of 0 0794s Next diethylene with a molecular weight of 106 12 Daltons had an average hemolysis time of 16 55 seconds with a standard deviation of 1 0889s Having the highest molecular weight of 150 17 Daltons triethylene had an average hemolysis time of 34 23 seconds with a standard deviation of 1 2401s Discussion After analyzing the results of this experiment it is clear that the results best support the alternative hypothesis The alternative hypothesis stated that if the molecular weight of a glycol molecule were changed then the time it takes hemolysis to occur would also change Therefore the null hypothesis should be rejected because our results demonstrated a significant change in hemolysis time when the molecular weight of a glycol molecule was changed More specifically our results demonstrated an increase in hemolysis time as the molecular weight of the glycol molecule increased The experiment was carried out to help develop an understanding of diffusion and membrane permeability Membrane permeability depends on the polarity size and the shape of the molecule trying to cross the membrane Our results demonstrated the more complex heavier the molecule the longer time the molecule takes to diffuse across the membrane or to hemolyze