Cell Membrane Permeability Lab Report
Purpose: Examine the role of the cell membrane in the cell by disrupting its function using temperature (Biology 107 Laboratory Manual 2014). This will improve the general understanding of optimal growing temperatures and the breakdown of the cell membrane
Procedure: Betacyanin solution of a known concentration was diluted to create a dilution series, then placed in a spectrophotometer set to 525 nm. The absorbance of the dilution was used to create a standard curve for betacyanin. Discs of living beet roots were then placed in water and exposed to various temperatures. A sample of the water that the beets were in was taken and absorbance was determined by the spectrophotometer and concentration from the standard curve for betacyanin.
Findings: In comparison to the control group the most distinct change in concentrations was present when the beet was exposed to temperatures of the extreme range. Either extreme cold at -5⁰C or extreme heat at 70⁰C in either case, the concentration of betacyanin present in solution was much …show more content…
The control group had a concentration of betacyanin of 0.09 µM while the -5⁰C test tube had a concentration of 23.5 µM, around 260 times more betacyanin leakage. Which suggests that there has been severe damage to the plasma membrane rendering it unable to perform its main function of being a selective barrier (Reece et al. 2011) leading to the flow of betacyanin out of the cell. While the concentration of betacyanin present in the test tube exposed to 40⁰C water was 1.13, the difference in concentrations is not as immense as compared to the concentration of betacyanin that had been released in the lower temperature, which could suggest that proteins of the phospholipid bilayer have been denatured but not destroyed (Siegel 1969). The control group of this experiment would be considered relatively valid because of the temperature of water it had been exposed to. Kluepfel and Smith (1999) state that
Procedure: Betacyanin solution of a known concentration was diluted to create a dilution series, then placed in a spectrophotometer set to 525 nm. The absorbance of the dilution was used to create a standard curve for betacyanin. Discs of living beet roots were then placed in water and exposed to various temperatures. A sample of the water that the beets were in was taken and absorbance was determined by the spectrophotometer and concentration from the standard curve for betacyanin.
Findings: In comparison to the control group the most distinct change in concentrations was present when the beet was exposed to temperatures of the extreme range. Either extreme cold at -5⁰C or extreme heat at 70⁰C in either case, the concentration of betacyanin present in solution was much …show more content…
The control group had a concentration of betacyanin of 0.09 µM while the -5⁰C test tube had a concentration of 23.5 µM, around 260 times more betacyanin leakage. Which suggests that there has been severe damage to the plasma membrane rendering it unable to perform its main function of being a selective barrier (Reece et al. 2011) leading to the flow of betacyanin out of the cell. While the concentration of betacyanin present in the test tube exposed to 40⁰C water was 1.13, the difference in concentrations is not as immense as compared to the concentration of betacyanin that had been released in the lower temperature, which could suggest that proteins of the phospholipid bilayer have been denatured but not destroyed (Siegel 1969). The control group of this experiment would be considered relatively valid because of the temperature of water it had been exposed to. Kluepfel and Smith (1999) state that