Date:
Title: An experiment to investigate how temperature affects the Permeability of beetroot cell membranes
Aim:
(Hypothesis :)
Introduction:
(Description )Beetroot cells contain a red pigment, which is stored in the cell vacuole and a vacuole membrane to prevent this leaking out of the cell surrounds it. Also, the cell membrane helps contain the pigment inside the cell. As the cell membrane is differentially permeable which does not allow the big red pigment molecule to diffuse out from the cell.(Principles )The cell membrane is consist of protein and lipids which(Hypothesis) will be dissolved after immersing in the organic solvent. Thus, the red pigment can diffuse out from the cell. Thus, we can measure the red intensity of each solution to compare the effect of permeability of each organic solvent. Treat all discs by washing with water so that any excess dye that will be leaked out due to damage caused by the knife will not affect the results.(Independent variables )- The different kinds of organic solvent.(Dependent variables )-The intensity of red colour of different solutions. (Controlled variables): Temperature - Due to the fact that membranes are made of proteins, temperature is a very important factor. At temperatures above approximately 50°C proteins begin to get destroyed; this would therefore increase the permeability of both the cell wall and the vacuole wall. This would make it impossible for us to distinguish as to whether it was the change in surface area or the temperature that caused any change in dye leakage. Time: When leaving the beetroot in the test tubes it must be ensured that they are in the water for exactly 20 minutes each. This will make sure that the same period of time is given for dye leakage to occur.
Procedure:
1. use cork borer to collect some beet root cylinders
2. use razor blade to cut beet root cylinders into disc
3. Wash the disc in order to remove the red pigment on the surface
4. add same volume of each...