Beetroot Biology Experiment Essay Example

table. 0% concentration should not be 0. because it has no alcohol in it, and the membrane should not have been permeable at all – this is probably due to random error. We see a dip in the absorbance at 50% and I have labelled this is as an anomalous result because the absorbance should be more than 40%. Finally, the 70% concentration has also been labelled as an anomalous result because it should show the highest absorbance, as it is the strongest solution of alcohol and should have damaged the membrane the most. Aside from these anomalies, the results show that as the ethanol concentration increases, the absorbance increases too.

This fits my hypothesis well, as the cell membrane would be more damaged, technically the lipid bilayer (fluid mosaic model). This layer is where molecules are transported in a controlled manner, thus destroying it would make the juices leak out. Evaluation To make this experiment a lot better we could have repeated it many times to increase the reliability of our results. We could have especially repeated the anomalous results that we attained as they are the ones most likely to be incorrect and invalidate our experiment the most.

We could also have double checked the calibration of the colorimeter before starting as this might have produced some systematic errors (we were quite unfamiliar with the use of a colorimeter too). Other random errors that might have occurred would be for example the cutting of the beetroot slices might not have been done accurately. Other variables were not controlled, such as the temperature (which was room temperature, which changes and is not

controlled in any way) which is also known to have an effect on the permeability of the membrane of beetroot – as there will be more kinetic energy when the temperature is increased.