Diffusion Through Membranes Lab Report
Title: Diffusion throughout the membranes
Lab Partner(s): Alexis Clouting
Date: 2/15/15
Abstract: In the content of the Module 2 we learned about Diffusion across cell membranes. We touched on the different types of cells and their functions. How things are transported in and out of cells. Learning about isotonic, hypertonic and even hypotonic solution. This is not my first time touching on this subject in my nursing career and I learned a way to remember what happens in the different solutions. This project was to see which solution was able to pass through the semi permeable membrane. I came to the conclusion that as we learned in this module some molecules are too large to pass through membranes and some are some are small enough to pass …show more content…
through just about all of them.
Introduction and Background: In this lab I determined whether Starch “Dialysis solution” or the IKI solution was able to pass through the dialysis bag. I also tested red and blue dye in a cornstarch filled petri dish. Each Dye had a different molecular weight and that played a part in their diffusion as well. My hypothesis was if the blue dye had a higher molecular weight then it would diffuse faster through cornstarch. I did research with the provided textbook as well as a few websites. I referenced Passive Transport - Taking the Easy Road. (2007, January 1). Retrieved February 15, 2015, from http://www.biology4kids.com/files/cell2_passivetran.
Method: The materials I used for one experiment was (1) 60 mL Corn syrup bottle (C12H22O11, Red and Blue Dye Solutions (Blue molecular weight= 793 g/mole; Red molecular weight= 496 g/ mole), (1) 9cm Petri Dish (top and Bottom halves), Ruler, Stop watch and Tape. I used clear tape to secure one half (either the bottom or the top half is fine) of the petri dish over a ruler. I made sure that I could read the measurement markings on the ruler through the petri dish. The dish was positioned with the open end of the dish facing upwards. I carefully filled half of the petri dish with corn syrup until the entire surface is covered.
I developed my hypothesis and proceeded with my experiments. I placed a single drop of blue dye in the middle of the corn syrup. I noted the position where the dye fell by reading the location of the outside edge of the dye on ruler. I repeated the process with the red dye. I recorded my data on the table.
The Second experiment (5) 100mL Beakers 10mL 1% Glucose solution, (4) Glucose Test Strips, (1) 100mL Graduated Cylinder, 4mL 1% Iodine-potassium Iodide, IKI, 5ml liquid starch, (3) pipettes, (4) Rubber Bands (Small), Stopwatch, water, scissors, 15.0 cm Dialysis Tubing.
Measure and pour 50 mL of water into a 100 mL beaker. Cut a piece of dialysis tubing 15.0 cm long. Submerge the dialysis tubing in the water for at least 10 minutes. I measured and poured 82 mL water into a second 100 mL beaker. While the dialysis bag was soaking, made the glucose/sucrose mixture. Using a graduated pipette to add five mL of glucose solution to a third beaker and labeled it “Dialysis bag solution”. Used a different graduated pipette to add five mL of starch solution to the same beaker. Mixing and pipetting the solution up and down the pipette six times. Used the same pipette that I used to mix the dialysis bag solution, removing two mL of that solution and placed it in a clean beaker. That sample served as my positive control for glucose and starch. Dipped one of the glucose test strips into the two mL of glucose/starch solution in the third beaker. After one minute had passed, recorded the final color of the glucose test strip. Used a pipette to transfer approximately 0.5 mL of IKI to into the two mL of glucose/starch solution in the third beaker. After one minute had passed, recorded the final color of the glucose/starch solution. I used a clean pipette, and removed two mL of water from the 82 mL of water and placed it in a clean beaker. I dipped one of the glucose test strips into the two mL of water in the beaker. After one minute had passed, recording the final color of the glucose test strip. Used a pipette to transfer approximately 0.5 mL of IKI to into the two mL of water in the beaker. After one minute had passed, recorded the final color of the water in the beaker After at least 10 minutes had passed, remove the dialysis tube and close one end by folding over 3.0 cm of one
end (bottom). Folded it again and secure with a rubber band. Make sure the closed end will not allow a solution to leak out. You can test this by drying off the outside of the dialysis bag with a cloth or paper towel, adding a small amount of water to the bag, and examining the rubber band seal for leakage. Be sure to remove the water from the inside of the bag before continuing. Using the same pipette which was used to mix the solution in Step 3, transfer eight mL of the solution from the Dialysis Bag Solution beaker to the prepared dialysis bag. Place the filled dialysis tube in beaker filled with 80 mL of water with the open end draped over the edge of the beaker. Allow the solution to sit for 60 minutes. Clean and dry all materials except the beaker with the dialysis bag. After the solution has diffused for 60 minutes, remove the dialysis tube from the beaker and empty the contents into a clean, dry beaker. Label it dialysis bag solution. Tested the dialysis bag solution for the presence of glucose and starch. Tested for the presence of glucose by dipping one glucose test strip into the dialysis bag directly. Again, waited one minute before reading the results of the test strips. Record your results for the presence of glucose and starch in Table 4. Test for the presence of starch by adding two mL IKI. Recorded the final color after one minute had passed. Tested the solution in the beaker for glucose and starch. Used a pipette to transfer eight mL of the solution in the beaker to a clean beaker. Tested for the presence of glucose by dipping one glucose test strip into the beaker. Waited one minute before reading the results of the test strip and recorded the results. Added two mL of IKI to the beaker water and recorded the final color of the beaker solution.
Results: The Red Dye diffused faster than the Blue. And the IKI solution was able to pass through the membrane due to it having smaller molecules. The starch had molecules to large to pass through the membrane.
Discussion: The Red ink diffused faster. I however did not get the result I thought I would get. The IKI solution moved in and out of the semi permeable membrane. I believed it would only because when I think of cornstarch I think of the white powdery substance I use to thicken my gravy. So I believed the molecules would be larger too large to pass through the dialysis bag. At this point in time I’m not sure what else I would test and have no plans in the near future to test other substances.
References:
Passive Transport - Taking the Easy Road. (2007, January 1). Retrieved February 15, 2015, from http://www.biology4kids.com/files/cell2_passivetran.html
Lab Partner(s): Alexis Clouting
Date: 2/15/15
Abstract: In the content of the Module 2 we learned about Diffusion across cell membranes. We touched on the different types of cells and their functions. How things are transported in and out of cells. Learning about isotonic, hypertonic and even hypotonic solution. This is not my first time touching on this subject in my nursing career and I learned a way to remember what happens in the different solutions. This project was to see which solution was able to pass through the semi permeable membrane. I came to the conclusion that as we learned in this module some molecules are too large to pass through membranes and some are some are small enough to pass …show more content…
through just about all of them.
Introduction and Background: In this lab I determined whether Starch “Dialysis solution” or the IKI solution was able to pass through the dialysis bag. I also tested red and blue dye in a cornstarch filled petri dish. Each Dye had a different molecular weight and that played a part in their diffusion as well. My hypothesis was if the blue dye had a higher molecular weight then it would diffuse faster through cornstarch. I did research with the provided textbook as well as a few websites. I referenced Passive Transport - Taking the Easy Road. (2007, January 1). Retrieved February 15, 2015, from http://www.biology4kids.com/files/cell2_passivetran.
Method: The materials I used for one experiment was (1) 60 mL Corn syrup bottle (C12H22O11, Red and Blue Dye Solutions (Blue molecular weight= 793 g/mole; Red molecular weight= 496 g/ mole), (1) 9cm Petri Dish (top and Bottom halves), Ruler, Stop watch and Tape. I used clear tape to secure one half (either the bottom or the top half is fine) of the petri dish over a ruler. I made sure that I could read the measurement markings on the ruler through the petri dish. The dish was positioned with the open end of the dish facing upwards. I carefully filled half of the petri dish with corn syrup until the entire surface is covered.
I developed my hypothesis and proceeded with my experiments. I placed a single drop of blue dye in the middle of the corn syrup. I noted the position where the dye fell by reading the location of the outside edge of the dye on ruler. I repeated the process with the red dye. I recorded my data on the table.
The Second experiment (5) 100mL Beakers 10mL 1% Glucose solution, (4) Glucose Test Strips, (1) 100mL Graduated Cylinder, 4mL 1% Iodine-potassium Iodide, IKI, 5ml liquid starch, (3) pipettes, (4) Rubber Bands (Small), Stopwatch, water, scissors, 15.0 cm Dialysis Tubing.
Measure and pour 50 mL of water into a 100 mL beaker. Cut a piece of dialysis tubing 15.0 cm long. Submerge the dialysis tubing in the water for at least 10 minutes. I measured and poured 82 mL water into a second 100 mL beaker. While the dialysis bag was soaking, made the glucose/sucrose mixture. Using a graduated pipette to add five mL of glucose solution to a third beaker and labeled it “Dialysis bag solution”. Used a different graduated pipette to add five mL of starch solution to the same beaker. Mixing and pipetting the solution up and down the pipette six times. Used the same pipette that I used to mix the dialysis bag solution, removing two mL of that solution and placed it in a clean beaker. That sample served as my positive control for glucose and starch. Dipped one of the glucose test strips into the two mL of glucose/starch solution in the third beaker. After one minute had passed, recorded the final color of the glucose test strip. Used a pipette to transfer approximately 0.5 mL of IKI to into the two mL of glucose/starch solution in the third beaker. After one minute had passed, recorded the final color of the glucose/starch solution. I used a clean pipette, and removed two mL of water from the 82 mL of water and placed it in a clean beaker. I dipped one of the glucose test strips into the two mL of water in the beaker. After one minute had passed, recording the final color of the glucose test strip. Used a pipette to transfer approximately 0.5 mL of IKI to into the two mL of water in the beaker. After one minute had passed, recorded the final color of the water in the beaker After at least 10 minutes had passed, remove the dialysis tube and close one end by folding over 3.0 cm of one
end (bottom). Folded it again and secure with a rubber band. Make sure the closed end will not allow a solution to leak out. You can test this by drying off the outside of the dialysis bag with a cloth or paper towel, adding a small amount of water to the bag, and examining the rubber band seal for leakage. Be sure to remove the water from the inside of the bag before continuing. Using the same pipette which was used to mix the solution in Step 3, transfer eight mL of the solution from the Dialysis Bag Solution beaker to the prepared dialysis bag. Place the filled dialysis tube in beaker filled with 80 mL of water with the open end draped over the edge of the beaker. Allow the solution to sit for 60 minutes. Clean and dry all materials except the beaker with the dialysis bag. After the solution has diffused for 60 minutes, remove the dialysis tube from the beaker and empty the contents into a clean, dry beaker. Label it dialysis bag solution. Tested the dialysis bag solution for the presence of glucose and starch. Tested for the presence of glucose by dipping one glucose test strip into the dialysis bag directly. Again, waited one minute before reading the results of the test strips. Record your results for the presence of glucose and starch in Table 4. Test for the presence of starch by adding two mL IKI. Recorded the final color after one minute had passed. Tested the solution in the beaker for glucose and starch. Used a pipette to transfer eight mL of the solution in the beaker to a clean beaker. Tested for the presence of glucose by dipping one glucose test strip into the beaker. Waited one minute before reading the results of the test strip and recorded the results. Added two mL of IKI to the beaker water and recorded the final color of the beaker solution.
Results: The Red Dye diffused faster than the Blue. And the IKI solution was able to pass through the membrane due to it having smaller molecules. The starch had molecules to large to pass through the membrane.
Discussion: The Red ink diffused faster. I however did not get the result I thought I would get. The IKI solution moved in and out of the semi permeable membrane. I believed it would only because when I think of cornstarch I think of the white powdery substance I use to thicken my gravy. So I believed the molecules would be larger too large to pass through the dialysis bag. At this point in time I’m not sure what else I would test and have no plans in the near future to test other substances.
References:
Passive Transport - Taking the Easy Road. (2007, January 1). Retrieved February 15, 2015, from http://www.biology4kids.com/files/cell2_passivetran.html