Activity 1: Simple Diffusion
Chart 1Dialysis Results (Average Diffusion rate in mM/min)
1)Which solute(s) were able to diffuse into the right beaker from the left? NaCl, Urea, Glucose
2)Which solute(s) did not diffuse?
3)If the solution in the left beaker contained both urea and albumin, which membrane(s) could you choose to selectively remove the urea from the solution in the left beaker? How would you carry out this experiment? 16 min 200 = 4.5 in both beakers
16 min 100 = 4.5 in both beakers
4)Assume that the solution in the left beaker contained NaCl in addition to the urea and albumin. How could you set up an experiment so that you removed the urea, but left the NaCl concentration unchanged? Hint: Assume that you also have control of the contents in the right beaker. Put 9mm of NaCl in the right beker - equals out the urea 100 MWCO
Activity 2: Facilitated Diffusion
Facilitated Diffusion Results
( glucose transport rate, mM/min)
(mM)No. of Glucose carrier proteins
2.00 .0008 .0010 .0012
8.00.0023 .0031 .0038
1)What happened to the rate of facilitated diffusion as the number of protein carriers increased? Explain your answer.
The rate of diffusion increased as rate of protein carriers increased. 2)What do you think would happen to the transport rate if you put the same concentration of glucose into both beakers instead of deionized water in the right beaker? The solutions are equal. No transfer will occur
3)Should NaCl have an effect on glucose diffusion? Explain your answer. Use the simulation to see if it does. No, the rate of diffusion is the same with NaCl added. NaCl has no transport proteins to aid in diffusing glucose.
Activity 3: Osmosis
Chart 3 Osmosis Results
(pressure in mm Hg)
1)Do you see any evidence of pressure changes in either beaker, using any of the four membranes? If so, which membrane(s)? Yes. The left beaker increased pressure
2)Does NaCl appear in the right beaker? If so, which membrane (s) allowed it to pass? Yes. 50, 100, 200
3)Explain the relationship between solute concentration and osmotic pressure. If the solute concentration increases, then the osmotic pressure increases.
4)Will osmotic pressure be generated if solutes are able to diffuse? Explain your answer. No. If solutes diffuse, then the solutions will equalize
5)Because the albumin molecule is much too large to pass through a 100 MWCO membrane, you should have noticed the development of osmotic pressure in the left beaker in the albumin run using the 100 MWCO membrane. What do you think would happen to the osmotic pressure if you replaced the deionized water in the right beaker with 9.00 mMalbumin in that run? (Both beakers would contain 9.00 mM albumin.) Nothing, Because they are equalized.
6)What would happen if you doubled the albumin concentration in the left beaker using any membrane?
The pressure will remained the same
7)In the albumin run using the 200 MWCO membrane, whatwould happen to the osmotic pressure if you put 10 mM glucose in the right beaker instead of deionized water? Explain your answer. The Albumin pressure remained 153 but 5.00 of the glucose diffused to the albumin beaker.
8)What if you used the 100 MWCO membrane in the albumin/glucose run described in the previous question? There is no diffusion, but pressure in the right beaker increased to 17mmHg....