Question

q8. a simcell with a water - permeable membrane that contains 50 dextrose molecules, 25 glucose molecules, 25 hemoglobin molecules and 900 water molecules is placed in an extracellular fluid that is one part solute to 15 parts water (its solute - to - solvent ratio is 1:15). which of the following should happen? more water molecules will flow from the simcell into the extracellular fluid than from the extracellular fluid into the simcell. more water molecules will flow from the extracellular fluid into the simcell than from the simcell into the extracellular fluid. there will be no movement of water molecules across the membrane. water molecules will move back and forth equally across the membrane.

Explanation:

Step1: Calculate solute - solvent ratio in SimCell

Total solute molecules = 50 (dextrose)+25 (glucose)+25 (hemoglobin)=100. Total water molecules = 900. Solute - to - solvent ratio in SimCell is $\frac{100}{900}=\frac{1}{9}$.

Step2: Compare ratios

Solute - to - solvent ratio in extracellular fluid is $\frac{1}{15}$. Since $\frac{1}{9}>\frac{1}{15}$, the SimCell has a higher solute concentration (lower water concentration) compared to the extracellular fluid.

Step3: Determine water movement

Water moves from an area of higher water concentration to an area of lower water concentration by osmosis. So more water molecules will flow from the extracellular fluid (higher water concentration) into the SimCell (lower water concentration).

Answer:

More water molecules will flow from the extracellular fluid into the SimCell than from the SimCell into the extracellular fluid.