Activity 1: Simulating Simple diffusion
1. What is the molecular weight of Na+? 22.99 or 23
2. What is the molecular weight of Cl-? 35.45
3. Which MWCO dialysis membranes allowed both of these ions through?50,100, 200
4. Which materials diffused from the left beaker to the right beaker? Urea, NaCl and glucose diffused
5. Which did not? Why? Albumin was too large to diffuse into the right beaker.
Activity 2: Simulating Dialysis
6. What happens to the urea concentration in the left beaker (the patient)? Its concentration gradient changes and causes it to move down.
7. Why does this occur? It happened because the more concentrated it became it causes the molecules to move down.
Facilitated Diffusion
Activity 3: Facilitated Diffusion
8. At a given glucose concentration, how does the amount of time it takes to reach equilibrium change with the number of carriers used to “build” the membranes? The time is faster to rach the equilibriums.
9. Does the diffusion rate of Na+/Cl- change with the number of receptors? Yes it does
10. What is the mechanism of the Na+/Cl- transport?
11. If you put the same amount of glucose in the right beaker as in the left, would you be able to observe any diffusion?NO there is no diffusion taking place.
12. Does being unable to observe diffusion necessarily mean that diffusion is not taking place? yes you should be able to tell when equilibrium is reached
Osmosis
Activity 4: Osmosis
13. Did you observe any pressure changes during the experiment? If so, in which beaker(s), and with which membranes?
Yes in the left beaker at the membrane 20.
14. Why?
15. Did the Na+/Cl- diffuse from the left beaker to the right beaker? If so, with which membrane(s)? No with any of the membranes.
16. Why? Because there is equal pressure on both sides.
17. Explain the relationship between solute concentration and osmotic pressure?as solute goes higher do does the osmotic pressure.
18. Does