Question

part 3: modeling osmosis in a cell

1. which of the three solutions (glucose, starch, and iodine) crossed the membrane? what evidence was collected to support this?

glucose and iodine cross the membrane. glucose is a change in concentration and iodine reacts with starch.
question 7
1 pts
part 3: modeling osmosis in a cell

1. why did these solutions cross and the other did not? in other words, what characteristics do they have that the other does not?

Explanation:

1. Glucose and iodine cross the membrane likely due to their smaller molecular size and the semi - permeability of the cell membrane. Glucose can cross via facilitated diffusion or simple diffusion depending on concentration gradients and the presence of transport proteins. Iodine can also pass through as it is a small molecule. Starch is a large polymer and cannot cross the membrane easily. Evidence for glucose crossing could be a change in glucose concentration on either side of the membrane. Evidence for iodine crossing is its reaction with starch on the other side of the membrane if present there, showing it moved across.
2. Glucose and iodine crossed because they are small - sized molecules. Starch did not cross as it is a large macromolecule. The cell membrane is semi - permeable, allowing small molecules to pass through by diffusion or other transport mechanisms, but restricting large molecules.

Answer:

1. Glucose and iodine crossed the membrane. Evidence for glucose: change in glucose concentration on either side of the membrane. Evidence for iodine: reaction with starch on the other side of the membrane if present there.
2. Glucose and iodine crossed because they are small - sized molecules. Starch did not cross because it is a large macromolecule and the cell membrane is semi - permeable, restricting large molecules from passing through easily.