Red beet tissue contains large amounts of betacyanin, a red pigment, located in the large internal membrane vacuoles. When the membrane is damaged, the pigment can cross the vacuole membrane and cell membrane. Since pigment is water soluble and not lipid soluble, it remains in the vacuole when the cells are healthy. If the integrity of a membrane is disrupted, however, the contents of the vacuole will spill out into the surrounding environment. This usually means the cell that made the vacuole is dead.
Variables.
Age of beetroot.
The age of the beetroot needs to be controlled as to prevent inaccuracies. The older the beetroot the more betacyanin and anthocyanins molecules present. This will therefore make the experiment unfair, because the more pigment molecules present the more pigment molecules that can move out of the cell. Therefore the beetroot used should be freshly cut. pH The pH is also an important factor, as pH can have an effect on the weak interactions and bonds that bound the membrane together. To keep the pH constant it is important to make sure that the same surrounding are used for the experiment.
Surface area.
The surface area of the beta vulgaris is another important factor as the greater the surface area of the beta vulgaris, the greater the concentration of pigment molecules the beta vulgaris will hold. It is therefore important that all the pieces of beta vulgaris used be of the same length and diameter.
Light intensity.
It is important that the investigation is carried out in the same light intensity because the absorption will be different for different intensities.
Colorimeter.
The same colorimeter should be used throughout the experiment to make sure that the accurarcy to which the