Cell Membrane Lab Report

Testing Cell Transportation Across a Membrane
Introduction
Cells have the amazing ability to transport certain molecules in or out of their membrane. Some require no energy to do so (passive transport) while others require energy to be processed through (active transport). There is also the transportation of water across a membrane, which has its own term of osmosis. Too much of something can be taken in, or too little enters. This especially happens to plants, who require water (and sun) to live. Not enough water, as herbalists or any plant lover will know, will cause the plant to wilt. However, why consider cell membrane transportation? Because it happens daily, whether it is a plant or our own bodies, this transfer of materials happens
First, label 6 test tubes a-f. Next, place the 100 mL beaker on the digital scale and zero the scale. Measure 17.1 g of table sugar by putting it in the beaker. Then measure a total of 50 mL of distilled water by using a 25-mL graduated cylinder. Using the stirring rod, slowly add the 50 mL and stir until the sugar is completely dissolved. This is now a 1.0 M (molarity) solution. Label a short stem pipet “DW” (distilled water), which will be used throughout the experiments. Use the 25 mL graduated cylinder to measure 5 mL of distilled water and add that to test tube “a”. Dry the graduated cylinder and wash with distilled water after each step after this. Use the graduated cylinder to measure 1 mL of the 1.0 M sucrose solution and use the “DW” pipet to add 4 mL of distilled water to test tube “b”, which is now a .2 M solution. Then use the graduated cylinder to measure 2 mL of 1.0 M sucrose solution and add 3 mL of distilled water to test tube “c”, which this creates a .4 M solution. Measure 3 mL of 1.0 M sucrose and 2 mL of distilled water to test tube “d”, which then creates the .6 M solution. Measure 4 mL of the 1.0 M sucrose solution and 1 mL of distilled water to test tube “e”, which creates the .8 M solution. Finally, measure 5 mL of the 1.0 M sucrose solution and add to test tube “f”, creating the 1.0 M
First, label 2 of the short plastic cups “1” and “2”. The, use the graduated cylinder to add exactly 150 mL of distilled water to cup 1. While preparing for the next step, place the dialysis tubing in cup 1 and let it soak for about 5 minutes. Use the “DW” pipet to add 4 mL of distilled water to the graduated cylinder. Add 2 mL of starch solution and 2 mL of 20% glucose solution to cup 2 and mix thoroughly with the glass rod. Next, cut 2 rubber bands in one place and set aside. By this time, the dialysis tubing should be ready to be removed from cup 1. Set cup 1 aside for future use. “Fold the dialysis tubing about 1 ½ cm from the end. Tie the snipped rubber band around the folded end of the tubing, creating a seal. Test the seal with a small amount of distilled water. Use the following procedures as a guide: To open the unsealed end of the dialysis tubing, carefully rub the tubing between your fingers until the middle of the tubing opens… Use the pipet labeled ‘DW’ to add a small amount of distilled water to the dialysis tubing. If the tube leaks, tighten the knot in the rubber band and repeat the test. Discard the distilled water used to test the dialysis tubing” (Taft 2015). Use a funnel on the open end of the dialysis tubing and slowly pour the glucose/starch solution from cup 2. Press air from the dialysis tubing and fold the end of the tubing tying the end closed with the other rubber band. Ensure