Ap Biology Dialysis Experiment

Improved Essays
Our goal of the dialysis experiment was firstly, to answer the question of why the dialysis cells appeared smaller after adding sugar water and secondly, to prove our hypothesis that water molecules move out of the cell because the concentration of water is greater than inside the cell than it is outside the cell. This experiment was conducted with one control group and one experimental group. The independent variable was the concentration of water, (water and glucose solution). The dependent variable was the size of dialysis cells afterward the lab, measured by the mass and the amount of water. The dialysis cell represents the plant cells in real life. The two pieces of dialysis cells (Cell A and Cell B), was filled in with 10mL of water. …show more content…
Cell A was 9.6 grams and Cell B was 9.63 grams before the experiment. Then, dialysis Cell A was placed in a cup with 70 mL of water, and dialysis Cell B was placed in a cup with 70 mL of 5% glucose and 95% water solution. The two dialysis cells were left in the water for three days. After three days, we removed dialysis Cell A and dialysis Cell B from each cup. After wiping the remnants of water on the outside of the dialysis cells, we placed each cell for the mass of the cell. Dialysis Cell A was 9.66 grams, while dialysis Cell B was 6.2 grams. The amount of liquid in each of the dialysis cells (Cell A & Cell B) was different. Dialysis Cell A had 8.6 mL of liquid inside the cell, and dialysis Cell B had 7.6 mL of liquid inside the cell. The mass of dialysis Cell A had increased 0.06 grams over the three days, and the mass of dialysis Cell B had decreased 3.45 grams over the three days. The amount of liquid in the cell in dialysis Cell A had decreased 1.4mL over the the three days, and the amount …show more content…
When we first started off the experiment, dialysis Cell A was placed in 100% water, which had an equal concentration outside and inside the cell. However, dialysis Cell B was placed in 5% glucose and 95% water solution, therefore making the concentration of water inside the cell (100% water), greater than the concentration of water outside the cell (95% water). This data has proved the concept of osmosis in the cells, related to our claim that water molecules move out of the cell because the concentration of water is greater inside therefore cell than it is outside the cell. The cells have to maintain a balance so that the concentration of water inside and outside the cell is equal. This is why the water molecules in Cell B had mostly moved out of the dialysis tubing to keep the concentration of water equal both outside and inside the cell. We also conducted the Benedict test for Cell A and Cell B. We saw that Cell A had no glucose, but Cell B had glucose. From this, we could see that both water and glucose moved through the selectively permeable membrane of the dialysis Cell B. The glucose moved inside the cell so that it could also balance out the concentration of water outside and inside the cell. This also proved the concept of osmosis as well, where the water moved outside of the cell because of the

Related Documents

  • Great Essays

    2.03 Lab Permeability

    • 1870 Words
    • 8 Pages

    Title: Alexandra Whitaker, Ms.Dayton, 12/23/16, 2.03 lab permeability Objective(s): The main purpose is to find out if plastic bags are permeable to starch and, or, iodine. Also, to find out wither potatoes are hypotonic, hypertonic, or isotonic by testing the different amounts of sucrose solutions Introduction: The necessary background information needed for this lab is the definition of osmosis, diffusion, active transports, passive transports, permeability, concentration, tonicity, and to now the scientific concepts of hypotonic, isotonic, and hypertonic. Hypothesis: For part 1 my hypothesis is: That the starch will diffuse across the plastic bag and react with the iodine and will have a color change to the water to imply the reaction…

    • 1870 Words
    • 8 Pages
    Great Essays
  • Improved Essays

    The iodine lab demonstrated the concept of diffusion, the movement of molecules move from a higher concentration to a low concentration through a semipermeable membrane. In the experiment, we observed a beaker filled with distilled water and Lugol’s iodine solution enter a bag filled with glucose and starch solution through the semipermeable membrane provided by the dialysis tubing. While the beaker remained the same color throughout, the solutions in the bag changed from a clear color to a light blue color due to the influx of iodine indicating the presence of starch. Although water molecules are polar, they are small enough to move across the membrane until it reaches an isotonic solution. There was also now a presence of glucose in the…

    • 690 Words
    • 3 Pages
    Improved Essays
  • Improved Essays

    Osmosis in Deshelled Chicken Eggs Brooke Sandy Partners: Alexa Smarra, David Egesigh, and Yousef Bahliawah Abstract Throughout the process of this experiment, chicken eggs were used to test how well certain solutions would be absorbed. The objective was to determine the rate and direction of osmosis into and out of cells according to their diffusion gradients.…

    • 942 Words
    • 4 Pages
    Improved Essays
  • Great Essays

    Tetrahymena Experiment

    • 1363 Words
    • 6 Pages

    The rate of how fast and slow contractile vacuole contracts in the Tetrahymena depends on what osmosis pressure it is in. The tetrahymena fills up with water and then contracts right before it bursts. Osmosis occurred in this experiment which affected the rate at which contractile vacuole contracts in the Tetrahymena. In a hypertonic solution, such as 500mM NaCI, water is already leaving the cell due to osmosis, a type of diffusion of water going from a high concentration to a low concentration or concentration gradient. Since the water is already leaving the cell, the contractile vacuole in the Tetrahymena does not need to work as hard to get water out of it.…

    • 1363 Words
    • 6 Pages
    Great Essays
  • Decent Essays

    Karo Syrup Case Study

    • 356 Words
    • 2 Pages

    The plant takes up water by osmosis and starts to swell. The cell wall prevents it from bursting. Animal cells don’t have a cell wall so the cells will burst in a hypotonic solutions. 3.…

    • 356 Words
    • 2 Pages
    Decent Essays
  • Superior Essays

    Dialysis Tubing Lab Report

    • 1179 Words
    • 5 Pages

    In this lab the dialysis was used for the diffusion and osmosis of iodine, glucose, starch and water. However, starch was unable to pass through the membrane due to it being too large. This is where it does not fully resemble a cell membrane because it can not transform and undergo things such as endocytosis to allow all the molecules to pass through. Conclusion…

    • 1179 Words
    • 5 Pages
    Superior Essays
  • Improved Essays

    Method: In this experiment each group received 2 chicken eggs whose shells have been dissolved off. This gave us a differentially permeable membrane so that we can observe osmosis and what happens when the membrane is presented with different solutions. Since we did not know the concentration of the egg, we had to assume that it equaled the concentration of the membrane. We then had the ability to determine the concentration based off the assumption and the rate of osmosis.…

    • 1466 Words
    • 6 Pages
    Improved Essays
  • Improved Essays

    This will act as our red blood cell. We did this again to leave us with 2 dialysis tubes full of water. We then filled one cup with 250mL of distilled water and another cup with 250mL of starch. We weighed the dialysis tubing one at a time then dropped one in the cup of water and one in the cup of starch. We repeated these steps except instead of water in the dialysis tubing we put starch.…

    • 527 Words
    • 3 Pages
    Improved Essays
  • Improved Essays

    This experiment was setup by filling up 4 dialysis tubes with a series of sucrose solutions, each containing the same amount of volume. These solutions each contain a different concentration, which will, in turn, affect each dialysis tube differently. leaving a small pocket of air for diffusion of materials, and sealing the tube using balloon clips. The tubes are then weighed for their initial mass and recorded. Each of these tubes are then placed in a beaker and fully immersed in water.…

    • 651 Words
    • 3 Pages
    Improved Essays
  • Improved Essays

    Dialysis Bag Lab

    • 542 Words
    • 3 Pages

    Then we added water to three different beakers, each being a different temperature. One beaker was room temperature, another was heated to about body temperature, and the last was ice water. Next, we added a dialysis bag to each of the three beakers. We let them sit for 5 minutes without disruption. After 5 minutes, we weighed the mass of the bags.…

    • 542 Words
    • 3 Pages
    Improved Essays
  • Decent Essays

    Two fifty milliliter of water was added to a beaker, with a size of two fifty milliliters with a sufficient amount of potassium iodide, making the water yellow in color. The dialysis tube was soaked in water for a few minutes until it opened up from both ends. One of the ends of the bags was folded and tied with a string, to close the end so that no solution is leaked through. The other end of the tube remained opened so that it forms a bag, and four milliliters of glucose and three milliliters of starch are added into the dialysis tube. The other end is, also closed and tied with string.…

    • 429 Words
    • 2 Pages
    Decent Essays
  • Improved Essays

    Homeostasis Lab Report

    • 666 Words
    • 3 Pages

    Introduction Homeostasis is the state of a stable internal cell environment. If the cell is not in a state of homeostasis, then the cell will not be able to live and function properly. The plasma membrane is selectively permeable and controls what molecules enter and exit the cell. The plasma membrane keeps the environment inside the cell relatively stable which is the state of homeostasis. The goal of this investigation is to see if the size of the cell is affected when the cells are put in different solutions of alcohol and water.…

    • 666 Words
    • 3 Pages
    Improved Essays
  • Decent Essays

    Osmosis Lab Report

    • 315 Words
    • 2 Pages

    The factor that determined the rate and direction of osmosis in the experiment was the amount of solute in the dialysis tube. This is shown through the amount of water that transferred into the dialysis tube as the sucrose concentration was raised. As the ratio from solute to water was heightened (as shown within the graph and data table), the amount of water that was transferred into the dialysis tube increased. From the data collected, it can be concluded that water and solute will move through the dialysis tubes to balance out the concentration, though in this case the tubing was not permeable to sucrose due to it’s size, seen in the increase in mass with each dialysis tube. For instance, when there was only a molarity of 0.2, the mass of…

    • 315 Words
    • 2 Pages
    Decent Essays
  • Improved Essays

    When red blood cells are submerged in saltwater, the saltwater solution is referred to a hypertonic solution. Opposed to a red blood cell being submerged into a freshwater solution that is defined as a hypotonic solution. When a human begins to drown in a hypertonic solution, the red blood cells begin to lose water, hence causing it to shrink as an effect of the solution having a greater concentration of solute than inside of the red blood cell. When the human is submerged into a hypotonic solution, the red blood cells begin to swell with water, hence causing it to expand because the solution has a lower concentration of solute. In lecture, we observed videos of red blood cells bursting in freshwater and red blood cells shrinking in saltwater.…

    • 533 Words
    • 3 Pages
    Improved Essays