Osmosis Lab Report

8. What type of membrane does the dialysis tubing represent? Give an example of this type of

In this lab experiment, half our group observed and measured osmosis using dialysis tubes that were represented as the semipermeable membrane. It is permeable to water and other small molecules but is impermeable to larger molecules such as the sucrose solution used in each of the four beakers and tubing. The other half of our group observed the tonicity of sheep blood to determine whether the blood was isotonic, hypotonic, or hypertonic. The 85 g/dL of NaCl solution was the ideal isotonic number in relation to the sheep blood cells as well as a reference to the other observations of the solutions.

The Osmosis and Diffusion lab was conducted to provide us with information on how built up mucus affects those conflicted by the recessive genetic disease, Cystic Fibrosis., due to a mutation to the membrane regulating chloride (Cl-). This mutation prevents the Cl- from leaving the cell causing the amount of sodium (Na+) in epithelial cells, which results in extreme mucus on the lungs and airways causing this disease to be fatal if not treated but treatment does not equate to a long lifetime. During the lab we took the data from three parts: Diffusion, Osmosis in an Elodea Cell, and finally the Role of Osmosis in Cystic Fibrosis. During Part 1 we looked at diffusion across a semipermeable membrane for starch and glucose, which resulted in both having a negative solution when placed in a semipermeable membrane. Then we looked at osmosis in the Elodea Cell to watch for the occurrence of Plasmolysis, when a cell’s plasma membrane pulls away from the cell, and how a plant cell is affected by both hypertonic and hypotonic solutions. Finally, we observed the role of Osmosis in Cystic Fibrosis using dialysis bags to represent a normal cell and a Cystic Fibrosis cell with the normal containing 1% NaCl while the Cystic Fibrosis bag contained 10% NaCl. After we ran the experiment, we looked at the Percent Change in Mass and compared them after 30 minutes. We found that Cystic Fibrosis cells didn’t change mass as much as the normal cell ending with a change in mass over -1%. The

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).

Open-ended Lab: Osmosis and Diffusion in Dialysis Tubing Name(s): Background: It is very difficult to measure or see osmosis actually occurring in cells because of the small size of most cells. However, if an artificial membrane that acts in some ways like a real plasma membrane could be found, than a study of osmosis using a model cell would be possible. Dialysis tubing is a manmade semi-permeable membrane that is used to treat people who have kidney failure. Dialysis is a process where substances in solution are separated by their difference in molecular weight (size). The driving force behind dialysis is the concentration difference between two solutions on opposite sides of the membrane. Materials: (per lab team) • 250 ml beaker • 1-

Using the graduated cylinder, measure 20mLs of the stock sucrose solution and 180mL of water to create a 3% sucrose solution and place it into the 250mL beaker (beaker #2). Place bags #1‐3 (red, blue, yellow) into beaker 2 and bag #4 (green) into beaker 1. Allow the bags to sit for one hour. After allowing the bags to sit for one hour, remove them from the beakers carefully open the bags, noting that often times the tops may need to be cut as they tend to dry out. Measure the solution volumes of each dialysis bag using the empty 250 ml beaker.

The hypothesis states that if the solution is hypotonic the results will decrease, if the solution is hypertonic the results will increase and if the solution is isotonic the solution will vary and or remain constant. In order to test the predictions of the hypotonic, hypertonic, and isotonic hypothesis for the solution  made during the study,  four samples of sucrose were taken and placed into two different beakers each containing a different concentration. Then dialysis tubing A was placed into beaker 1 with B, C, and D placed into beaker 2 for 45 minutes and weighted at 15 minute intervals. My finding in the study was that each of the four samples changed from their initial weight and for the most part accurately proved the hypothesis.

One dialysis tube was submerged in each beaker. Osmosis was allowed to occur for 5 minutes and then all of the tubes were removed from the water. The tubes were dried off and measured on the triple beam scale. The mass was taken and recorded for all three tubes. I then placed the tubes back into their respective solutions. The process was repeated four times for each tube in 5 minute increments, and then the materials were disposed of. The rate of diffusion of water in each solution was

Osmosis is defined as the tendency of water to flow through a semipermeable membrane to the side with a lower solute concentration. Water potential can be explained by solutes in a solution. The more positive a number is more likely it will lose water. Therefore should water potential be negative the cell the less likely it will lose water. In using potatoes the effects of the molarity of sucrose on the turgidity of plant cells. According to Clemson University, the average molarity of a White potato is between .24 M and .31 M when submerged in a sorbitol solution. This experiment was conducted with the purpose of explaining the relationship found between the mass in plants when put into varying concentrations of sucrose solutions. Should the potatoes be placed in a solution that contains 0.2M or .4M of sucrose solution it will be hypotonic and gain mass or if placed in .6M< it will be hypertonic and lose mass instead. Controlled Variables in this lab were: Composition of plastic cups, Brand of Russet Potatoes, Brand of Sweet Potatoes and the Temperature of the room. For independent variable that caused the results recorded it was the different Sucrose concentrations (0.0M, 0.2M, 0.4M, 0.6M, 0.8M, 1M). The dependent variable was the percentage change from the initial weighs to the final. The cup with .4 molarity was the closest to an isotonic solution and was used as the control group for the lab. Water potential is the free energy per mole of water. It is

Next, gather 0.5 ml of the protein extract and save this portion in a separate container. This will be used for the preparation of the membrane.

Machine set up is the most important process of initiating treatment because it is what the patient is directly connected to it. The outside of the machines are cleaned with a bleach and water solution the day before and in between patients. Saline and the artificial kidney called a dialyzer are connected to the machine using plastic tubing or “lines”. After connecting everything the lines are “primed” or rinsed with saline to remove any air or disinfectant from the lines. This will prevent air or chemical from getting in contact with the patient’s blood. Once the Lines are primed, the machine is tested to make sure that all alarms and compartments are working properly. After the machine is tested the saline is then circulated through the lines once again to make sure everything is running properly. After all of these steps the machine is safe enough for the

Dialysis is generally only considered an option when more than eighty percent of the kidney is unusable, damaged, and unable to carry out its functions. The prominent feature of dialysis is to filter out wastes and clean the blood in order to have the same effect that a healthy kidney would. There are two primary types of dialysis; hemodialysis and peritoneal dialysis. In hemodialysis, a hemodialyzer, or an artificial kidney, is placed in the body and cleans the blood in the body. To get the blood into the hemodialyzer, surgery has to be done on the leg or arm. There are two main components, one for the blood and one for dialysate, a washing fluid. Blood is removed from the body and filtered through a man-made thin membrane, the dialyzer. Blood cells and proteins are too large to pass through the membrane, while waste products, such as urea, potassium, and extra fluid are able to travel through the dialyzer. The blood is then returned to the body. In peritoneal dialysis, a cleansing fluid flows through a catheter, which is placed in the abdomen, in order to filter out waste products within the flood. After a period of time where the filtering process is completed, the fluid containing the wastes is removed through the tube and

In this lab the act of osmosis will be shown in gummy bears when added in different kinds of liquids. To begin the experiment, there’s a need of understanding of the movement of cells and what happens when substance goes in or leaves a cell. What gives molecules permission to go in and leave a living organism's cell is the cell membrane. The cell membrane is able to choose when to become “spongy” in living organisms. It can also distinguish molecules even though they might be the same size, and this is the difference between a non-living thing and a living organism. Some things that are non-living do allow some substances or molecules to leave and enter them, though it can’t separate some of the molecules.(2)

The graph illustrates the change in weight of each dialysis tube every 5 minutes for 20 minutes’ total. For this graph I subtracted the initial weight of each tube from the weight at each interval. The less molasses in the dialysis tubes, the less water moved from outside the tube into the tube. This is a noticeable trend. It appears that the more molasses in each bag, the more weight each bag gains.

This experiment’s purpose is to view the effects of Osmosis and Diffusion on a cell membrane replacement. This is being shown on an increased scale by using dialysis tubing as a replacement for the cell membrane. This is replicating the way a cell membrane acts when placed in an environment where the fluid inside can leave the cell.