The movement of water molecules across a semi-permeable membrane is the process of osmosis. If there is a solute and a solvent, each containing different concentration levels, then the water would move along its concentration gradient until each side of the membrane are equal. The water moves because the membrane is impermeable to the solute and the solute concentrations may differ on either side of the membrane. Water molecules may move in and out of the cell, but there is no net diffusion of water. Water will move in one direction or the other, and this is determined by the solute or solvents concentration levels. If the two solutions are of equal concentrations, they will be isotonic. If the concentrations are unequal, the …show more content…
This was due to the fact that both were isotonic, and with this, we can infer that the potato contains 0.2 mol/L of sucrose solution.
Discussion and Analysis
The percentage of change in mass if the sucrose solution had the same solute concentration as the potato section would be 0%. This is due to the fact that the change in mass occurs in osmosis. Osmosis occurs when an area of higher concentration is trying to get to an area of lower concentration in a semi-permeable solution. If the concentrations are the same, being isotonic, there would be no osmosis occurring, and therefore no change in mass. This occurred when there was a 0.2 mol/L concentration of the sucrose solution, therefore we can justify that the potato had that same concentration.
Figure 1.4: Graph Results After 24H in Solute Concentration With Labeled Hypotonic, Hypertonic, & Isotonic
The above graph is similar to that of Figure 1.3, but this has labeled which solutions were hypertonic to the potato cytoplasm, which were hypotonic, and which was isotonic.
As the concentration of the sugar increases, the more mass the potatoes would lose. This would make the potato hypertonic. This is because when potatoes are in sugar solution that is of a higher concentration of sugar than the cell sap, (cytoplasm in a plant cell), the water moves out of the cell causing the reduction in mass. Opposite of this, when the potatoes are in a lower sugar concentration