Preserving Beet Cells
Floor Location : J 166 D
I chose to perform this experiment because I wanted to see if cells could be frozen and preserved without damage. This is important because plant cells may be frozen for future use when they are not available or not in season which can impact places that cannot grow food due to extreme weather or environmental conditions.
All cells contain water and water expands when it is frozen. Cells are surrounded by a membrane, which can break if there is trauma to the cell. The freezing of the water inside the cell is one factor that may rupture the membrane. I think if the water inside the cells are removed, the possibility of them rupturing will be decreased.
I chose to use beet cells because of their colour. The pigment is contained inside the membrane and it’s easy to measure the amount of colour in the solution. If the solution becomes purple it demonstrates that the pigment has come out of the cell and into the solution because the membrane of the cell has ruptured. Removing the water from the cells can be done by osmosis which is the process of water moving to a more concentrated solution, so in this case, out of the cell into a concentrated solution.
My experiment showed that the 10 % salt solution at -18C caused the least amount of damage to the cell membrane. The higher salt concentrations, 30 % and 50%, led to more damage. I hypothesize that this is because water moved out of the cells to quickly causing breakage of the membrane and leakage of the pigment. The solution without any salt caused breakage as well. My hypothesis for why this occurred is that the water moved into the cell from the solution due to reverse osmosis. The excess water caused the cells to burst, leaking of the pigment into the solution. The experiment was conducted at refrigerator temperature, 4C and at freezer temperature, -18C. The refrigerator temperatures are not ideal for preserving cells. The optimum concentration and temperature for preserving cells about 10% and -18C.
Some extensions or further research I could do is to conduct this experiment using human cells to see if they would behave in the same manner.