There were 3 different tasks that were simultaneously done at the same time. First, a 250ml beaker filled with DH2O mixed with 20 drops of Iodine Potassium Iodide (IKI for short) was retrieved. Then,15-20 ml of 15% m/v glucose solution mixed with 1% m/v starch solution was brought. Finally, the presoaked dialysis tube was taken back to the station. Goggles, an apron, and gloves where worn for safety purposes because IKI is irritant to the skin. The dialysis tube was presoaked in water before the lab so that it would become more pliable. The materials used for this lab were a 250 ml beaker, 4 glucose testing strips, a dialysis tube that was greater than or equal to 12 centimeters in length, a 50 ml beaker, DH2O, IKI solution, 15% m/v glucose solution, 1% m/v starch solution, a quadruple beam balance …show more content…
Then 50 ml beaker with the glucose and starch mixture was also tested for glucose with a glucose strip. The dialysis tube was then clipped on one end and opened on the other end. The 15 ml of glucose and starch mixture was then poured into the dialysis tube with a pipette. The dialysis tube was then twisted and clipped on the unclipped end of the tube. The mass of the tube was then measured by a quadruple beam balance. The tube was then rinsed in the sink and blotted dry by a paper towel to clean the tube in case some of the glucose accidentally spilled out of the tube. The tube was then placed into the 250 ml beaker and left there to sit for 15 minutes. After 15 minutes, the 250 ml beaker was then tested for glucose with a glucose test strip and so was the contents inside of the tube. All observations and results were recorded in the chart below the procedure. Such observations listed were things like color change in the solutions, mass changes in the dialysis tubing, and what the glucose strips would indicate about the solution
Three peaks are observed in Figure 1 (concentration of glucose vs. elution volume) which was expected due to the results in table 4 that show intervals of elution. The intervals of the elution are represented as peaks on the graph. The intervals are due to the glucose molecules that enter the beads of the column causing the glucose molecules to elute slowly. Two peaks are observed in Figure 2 (concentration of starch vs. elution volume), which was not expected. One peak was expected for the
4. Does the dialysis bag or the beaker contain more starch? What about glucose? The dialysis bag does contain more of the glucose and starch than the beaker does.
In which two of the dialysis bag contain tap water. The three other Bags were 20% sucrose 40% sucrose and 60% sucrose. To perform this lab we prepare each of 5 bags with their designated sucrose solution. In this experiment the dialysis tubing acted as selectively permeable membrane. The dialysis bag allows the passage of water molecule only because the sucrose molecule are too large to pass through the membranes. After filling those bags ,we then placed the bags into five separate beakers. Four of this beakers contained only tap waters, and the fifth beakers contains solution of 60% sucrose. We filled the first dialysis bag with 10 ml of tap water, next we filled the second bag with 10ml of 20% sucrose, the third bag was filled with 10 ml of 40% sucrose solution while the fourth bag was filled with 10ml of Tap water (H2O). We made sure that when filling this bags that we removed as much air as possible before clamping of the end of each bag. We also made sure that all of the bags rest soft and floppy instead of firm to ensure that experiment will work properly. Next we placed dialysis bag ,one through four in their own separate beakers which was filled with tap water (H2O), and our fifth bag was full of tap water was placed in beaker filled with just enough of the 60% sucrose solution to cover the bag. All of these bags remained in their designated solutions for 45 minutes. However, all of this bags were quickly removed every
The independent variable in this lab is the molarity of sucrose each dialysis bag is filled with. The time (30 minutes), the temperature (23C) and the type of dialysis tubing used are all constants.
We hypothesize that as the solute concentration increases, more water will diffuse into the dialysis tubing (shown by a greater percent increase in mass).
At the end of the 75 minutes, two 1.0 mL samples of the albumin/glucose solution from the beaker were added to two test tubes labeled solution end. Then, the dialysis tube was removed from the beaker and rinsed off with distilled water. Once the tubing was rinsed and blotted dry the final water weight was recorded. After measuring the final water weight, the contents in the tubing was dumped into a beaker and 1.0 mL of starch/sodium sulfate solution was added to two test tubes labeled bag end (Keith et al., 2010).
The dialysis tubing will be clamped at one end in order to fill it and then clamped at the other end to seal the filled bag. If the bag is not soft and floppy, the experiment will not work. Blot a bag with a paper towel to absorb the moisture and weigh it, if this blotting process is not done it could interfere with the weight readings creating inaccurate information. After the bags of the solutions are prepared, they will be placed into five different beakers with different solutions. Beakers 1-4 will be filled with tap water and the fifth beaker is filled with 40% sucrose and water. Fill each beaker with just enough water or solution so that the bag is covered and place the bags in the beakers simultaneously and record each time. Every 10 min the bags are to be taken out, blotted, and weighed again before returning them back into their respective beaker for another 10 min. The process is repeated until you have reached 90 min. The weights should be recorded in grams (g).
Procedures Pre-Lab: Gather all materials for the experiment. Read all instructions Part One: Creating the Model Gather the supplies needed for the creation of the model. A roll of the suggested dialysis tubing, a plastic water bottle, the air line tubing, the tubing connectors, a large empty milk carton, a rubber band, 2 large plastic sandwich bags, a fluid transfer siphon pump, and a pair of scissors. First, open the carton of milk by cutting the bottom of the empty milk carton.
There were several steps completed to prepare for the experiment. Three dialysis tubes were filled with approximately the same volume of distilled water and then were tied shut. The initial mass (in grams) of the tubes was taken using a triple beam scale. I then filled three 500 mL beakers with 400 mL of water each and dissolved different masses of solute (table sugar) in each beaker in order to make 5%, 10%, and 20% solutions. The beakers were labeled accordingly, and then 20 g, 40 g, and 80 g (respectively) of table sugar was weighed out using a digital scale and placed into the corresponding beakers. The sugar was stirred in using a stirring rod until all of the solute was completely dissolved.
In the final experiment we filled a dialysis bag with starch solution and tied off both ends of the bag so that it is water tight. We then filled a separate bag with sodium chloride and submerge both dialysis bags in two beakers of distilled water. We allowed the bags to sit in the water for 10 minutes. We then put silver nitrate into the water that held the dialysis bag filled with sodium chloride and recorded any changes in the water. We then added iodine to the water that held the dialysis bag of starch and observed any changes in the water.
Table 1. Demonstrating the amount of glucose in each test tube Temperatures Test Tube 1 ±50 test tube 2 ±50 Test tube 3 ±50 25oC 550 500 500 37oC 650 700 650 0.8oC 300 350 350 100oC 0 0 50 Positive glucose Control, 25oC 900 900 850
The tubes are removed using a clamp and the concentration of maltose is compared using the following scale: red (+++), orange-yellow (++), green (+), blue (-).
The beaker was then filled partially with distilled water; 1 ml of potassium iodide was then added, and the solution was tested for the presence of glucose. This data was recorded in table 1 on the data sheet along with the starting color of both the potassium iodide solution and the glucose/starch solution. The dialysis tubing was then submersed into the beaker containing the potassium iodide solution, and set aside for 30 minutes to allow maximum diffusion.
The correct syringe is used to place 10 cm3 of the first glucose solution into the boiling tube.
Diffusion through the tubing would indicate that certain sized molecules can pass through the simulated permeable membrane. It would also indicate that amylase was able to break down starch into a small enough particle to allow diffusion to occur. The null hypothesis would be supported if the amylase did not affect the permeability and breakdown of the starch. The independent variable is the amylase and the dependent variable is the diffusion of starch through the membrane of the tubing. The control is the dialysis tubing without amylase, containing only starch.