2. Describe what needed to be done to each food sample, before it began to react on its own. (hint the results listed in the chart is based on the experiment, where the food samples were heated, thus also heating the water. Explain Why this is not an option for living cells.

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The diagram below shows three different proteins embedded in a cell membrane, as well as the concentration gradient surrounding the cell high concentration channel protein carrier protein lipid bilayer 1 21 3 low concentration Which of the following statements correctly states the process shown in the diagram? O The process labeled 1 shows how cells can easily move molecules with the concentration gradient using high energy molecules. The process labeled 2 shows how cells move molecules against the co entration gradient without needing hic energy molecules The process labeled 3 shows how cells use energy to facilitate the active transport of molecules against the concentration gradient All three processes show how molecules freely move in and out of the cell regardless of the concentration gradient or available en Previous

10)You observe a cell in a solution swelling until it bursts. You have seen an instance of osmosis in Select one: a. a hypertonic solution. b. an isotonic solution. c. a hypotonic solution. d. an exotonic solution.

2. Suppose you had allowed your dialysis experiment to continue for several days (with the beaker covered to prevent evaporation). At the end of that time period, you cut open the dialysis bag and pour the contents of the sausage into a clean beaker. If you were to test that sausage solution, what would you expect to be present in it? Why? C. OSMOSIS WITH AN ARTIFICIAL MEMBRANE b. a. Procedure For this experiment you will be making three more dialysis tubing sausages. This time fill all three sausages with 10 ml of a 10 percent sucrose solution. After you tie off each sausage, remember to trim off any excess floss and tubing and to rinse the sausage in tap water and pat it dry with a paper towel. Now, weigh each sausage using a triple beam balance and record the weights in the Results section below. Be su to keep track of which weight corresponds to which sausage. Place the first 100 ml labeled beaker filled with distilled water. Place the second sausage in a 100 ml sausage in labeled…

3. Equal numbers of fibroblasts and endothelial cells are present initially in a culture. a. If the endothelial cells double every 40 hours and the fibroblasts double every 20 hours, draw a graph showing the percentage of cells in the culture that are fibroblasts as a function of time (you can use excel). b. Come up with an equation to determine the time at which 90% of the cells will be fibroblasts and solve for time. Explain how you came up with your equation.

7. Use your knowledge of osmosis to explain your experimental results. Hint: The tubing is made of a selectively permeable membrane, so you know osmo- sis must have happened, but you should explain the situation in terms of molecules moving into and out of the tube. 8. A salt solution that contains 20% salt contains 80 % water. 9. If you were told that a type of cell contained about 2% salt, what would happen if you put the cells into a solution of 18% saline? It would swell because 18076 of Saline is cn hypotonic solution and cell hes salt concentration and low water but in saline low salt and high water is present so th water will enter the cell by osmosis and swells up the cell.

3) (If you had a cell that contained 5% glucose and would only allow water through its membrane, and you put it into the following solutions, write out which direction water could move, into out of or equally into and out of the cell, and describe what would happen to the cell? a. Water b. 2.5% NaCl c. 2.5% Fructose d. 2% Sucrose 2% KCl

1.Base on your understanding of plant and animal cell osmosis, what condition do you think plant cells prefer? 2. What condition do you think animal cells prefer? Consider the question: How is solute concentration related to the change in the weight of plant cells (like potato cells)? 5. Write a hypothesis from the above question. Write one if statement and make three predictions(then statements) regarding how the cell will change (weight) in (1) hypertonic,(2) hypotonic, and (3) isotonic conditions:

2. Kidney dialysis machines use osmosis to take over the filtering function of the kidneys. Dialysis machines use a semi-permeable membrane trough which some small molecules can pass (such as water, salts, metabolites, and somedoxins) but through which larger objects (such as proteins and blood cells) cannot. Using the concepts learned in this lab, explain how dialysis could be used to get toxins out of the blood and replace the filtering function of the kidneys.