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A student investigates osmosis using Visking (dialysis) tubing to model a cell membrane. Three lengths of tubing are each filled with 10 cm³ of 10% sucrose solution and tied at both ends. Each tubing is placed in a beaker containing a different solution:
- Beaker A: distilled water (0% sucrose)
- Beaker B: 10% sucrose solution
- Beaker C: 20% sucrose solution
After 30 minutes, the tubing is removed, blotted dry, and the final mass recorded. The results are shown in the table.
| Beaker | Initial mass (g) | Final mass (g) | Change in mass (g) |
|---|---|---|---|
| A | 12.5 | 14.2 | +1.7 |
| B | 12.5 | 12.5 | 0.0 |
| C | 12.5 | 11.0 | -1.5 |
Compare the movement of water into and out of the Visking tubing in the three beakers, and explain the results in terms of water potential. Then compare what would happen if a plant cell with a similar internal concentration were placed in each of the same three solutions.