Elizabeth is conducting an investigation to study how molecules are transported into and out of a cell. Elizabeth builds a model of a cell using a U-shaped tube. A barrier, which is permeable to water, but not sugar, is placed on the bottom of the tube to model the cell membrane. Elizabeth adds two different solutions to each side of the tube. The solute in each solution is sugar and the solvent is water. The initial levels of solution in Side A and Side B are equal. The concentration of sugar in Side A is lower than the concentration of sugar in Side B.

The given question is incomplete, the complete question is:

Elizabeth is conducting an investigation to study how molecules are transported into and out of a cell. Elizabeth builds a model of a cell using a U-shaped tube. A barrier, which is permeable to water, but not sugar, is placed on the bottom of the tube to model the cell membrane. Elizabeth adds two different solutions to each side of the tube. The solute in each solution is sugar and the solvent is water. The initial levels of solution in Side A and Side B are equal. The concentration of sugar in Side A is lower than the concentration of sugar in Side B.

What is Elizabeth likely to observe?

A. Water molecules will move from Side A to Side B. The solution level on Side A will fall and the solution level on Side B will rise.

B. Water molecules will move from Side B to Side A. The solution level on Side A will rise and the solution level on Side B will fall.

C. Sugar molecules will move from Side A to Side B. The solution level on Side A will fall and the solution level on Side B will rise.

D. Sugar molecules will move from Side B to Side A. The solution level on Side A will rise and the solution level on Side B will fall.

The correct answer is statement B, that is, the molecules of water will move from side A to side B. The level of solution on the side A will fall and the level of solution on the side will elevate.

Explanation:

Based on the given information, it is clear that the barrier is only permeable to water, thus, movement of water will take place through osmosis down the gradient, that is, from lower to the region of higher solute concentration. The water seems to equalize the concentrations of solute present on side A with the concentrations of solute present on side B.

Osmosis refers to a phenomenon in which the molecules of solvent seem to pass via a semipermeable membrane from the area of less concentration to the area of higher concentration, therefore, equating the concentrations on both sides of the membrane.