A Plasma Membrane Model
Use to complete Table 1: Before
The plastic bag is used to represent the plasma membrane. Inside the bag is a starch solution. Outside the bag is an iodine solution.
Use to complete Table 1: After
When iodine and starch are combined, the solution turns blue-black. We can therefore see that iodine did move through the plastic into the bag; however, the starch did not move outside the bag. If starch had moved, the iodine solution in the beaker would also be blue-black.