Activity 1: Simple Diffusion
Chart 1 Dialysis Results (Average Diffusion rate in mM/min)
Solute Membrane (MWCO) 20 50 100 200
NaCl (—) 0.0150 0.0150 0.0150
Urea (—) (—) 0.0094 0.0094
Albumin (—) (—) (—) (—)
Glucose (—) (—) (—) 0.0040
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?
Albumin
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
Chart 2 Facilitated Diffusion Results
( glucose transport rate, mM/min)
Glucose
concentration
(mM) No. of Glucose carrier proteins 500 700 900 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