Usman Omid Biology IB 1A
The Effect of Temperature on Beetroot MembranesAimThis practical will test the effect of temperature on the integrity of the membranes,IntroductionThe cells of beetroot contain a pigment called betalain in their vacuoles. It is kept inside the cells by the membranes. If these membranes are damaged, then the betalain leaks out. The amount that leaks out can be assessed, as the leaked out pigment will color the water surrounding the cells. This information can be used to find out how temperature affects cell membranes.HypothesisExposing the beetroot cells to a liquid environment (in this case water) with a temperature of 0 oC will keep the membranes intact because there is not energy transferred to the membrane and so it will not be bursting. The results are going to be more or less the same, until we exceed a temperature of 50 oC, because at this temperature most proteins will begin to denature. Then, if we increase the temperature above this, the cell membranes (which are made of proteins) will denature and soon burst and then the betalain will leak out and color the water red. As we keep increasing the temperature, the more betalain will leak out because the cell wall ought to burst faster with higher temperature and it is more certain that all cells will burst. When a cell wall bursts, it requires energy. This energy it takes from the nearby heat that is in the surrounding water. As it takes energy, the temperature of water in the surroundings will decrease. If we have the cells in a temperature of 50 oC, some cells will denature, but then the temperature of the surrounding water will decrease and the remaining cell membranes will not burst. Therefore it is more secure to state that all cells will denature in a water temperature 80 oC than 50 oC. It is also safe to state that the amount of leaked betalain will only continue to some level, but then, when there are no more cells with intact cell walls, more cells cannot be burst there will not be more betalain to extract from the vacuoles.Concluding this gives: If the temperature is increased, then more betalain will leak out of the cell to a certain point.ResultsPresentation of DataTab. 1: The amount of betalain leaked out from beetroot cells that were placed in different temperatures measured in arbitrary units. Data collected using a spectrometer that was set at 540 nm.
Amount of betalain leaked out measured with arbitrary unit ± 0.01
Temperature /oC ± 1 oC
In most groups the leaking of betalain, or the coloring...