Beet Lab

Only available on StudyMode
  • Topic: Cell membrane, Water, Solvent
  • Pages : 3 (836 words )
  • Download(s) : 124
  • Published : May 19, 2005
Open Document
Text Preview
Stability of cell membrane using pH
For the lab experiment for testing the stability of beet cell membranes using pH, many materials were used as follows. Obtaining a beet we punch out cores, using a cork borer. After washing the cores we put each one inside a separate test tube, and added a different pH solution in each one. After 3 minutes in these exposure solutions, we took the beet out with a dissecting needle. Then transferred each beet to a separate test tube containing deionized water. After 20 minutes in these diffusion solutions, we took the beets out with a dissecting needle and discard it. We then stirred each solution in the test tube with a stirring rod, and transferred it to a cuvette. A spectrophotometer was then calibrated, and used to measure the absorbance of each exposure solution, and diffusion solution.

Membrane Damage
For the lab experiment for Membrane Damage, we tested the extract pigment and diluted it. When the pH solutions are added, this will cause it to be in a range of absorbance. We used materials as follows. Obtaining a beet we proceeded to cut small individual cubes. We then rinse each cube to remove any damaged pigments with deionized water. Using a blender, we blend the beets with 15 mL of pH 7 DI water. After blending we used cheesecloth to separate the liquid from the solids for easier centrifuge process. Then we put the liquid beet into a centrifuge tube and centrifuge it for 5 minutes at 2500 rpm. We then remove the supernatant into a beaker, and discarded the sediment. Using a 1:4 ratio mixture of the supernatant and deionized water, we made a stock solution. We then tested the stock solution's absorbance with a spectrophotometer, and place 1 mL of the solution into separate test tubes. Next we added an additional 4 mL of pH solutions in the 2-11 range into each test tube. After mixing, we tested the absorbance for each solution using a spectrophotometer.

Mixing the Diffusion and Exposure...
tracking img