Osmosis Gizmo Explore Learning

ASSESSMENT QUESTIONS: ANETRA RODGERS Q1 Q2 Q3 Q4 Q5 SCORE Your Results saved for class Bio 2A      5/5 Questions & Answers 1. A normal plant cell holds water in the vacuole of the cell. This large organelle also gives the cell support. Suppose a plant is submerged in salt water. As a result, the vacuoles collapse and the leaves wilt. This condition is called plasmolysis. Which explanation do you think best describes what happens to the cells of that plant during plasmolysis? A. The water diffuses out of the cell to equalize the solute concentrations. B. The water diffuses into the cell to equalize the solute concentrations. C. The solute (salt) moves inside the cell to equalize the solute concentrations. D. The solute (salt) pushes on the vacuole of the plant cell causing it to collapse. Correct Answer: A. The water diffuses out of the cell to equalize the solute concentrations. Explanation: When the plant is submerged in salt water, the solute (salt) concentration is greater outside the cell membrane than inside. In order to reach equilibrium, water diffuses out of the cell to equalize the solute concentration. You answered this question correctly! 2. The images below show the same cell, before and after reaching equilibrium. Which statement best describes what happened as the volume of the cell increased? A. The number of solute particles inside the cell decreased. B. The number of solute particles outside the cell decreased. C. The number of solvent particles inside the cell decreased. D. The number of solvent particles outside the cell decreased. Correct Answer: D. The number of solvent particles outside the cell decreased. Explanation: As the solution reached equilibrium, the number of solvent particles decreased outside the cell and increased inside the cell. The volume of the cell increased as the solvent diffused through the cell membrane. This caused the cell to get bigger. You answered this question correctly! 3. Which of the following bar charts describes a system that is in solution equilibrium? A. Graph A B. Graph B C. Graph C D. Graph D Correct Answer: D. Graph D Explanation: Graph D shows that the solute concentration inside and outside the cell are equal, which indicates equilibrium. The bar charts in Graphs A, B, and C show that the solute concentrations are not equal inside and outside the cell. You answered this question correctly! 4. Using the information below, what will happen to the cell as it reaches equilibrium? A. The cell will get smaller. B. The cell will get bigger. C. The cell will stay the same size. D. The change in cell size cannot be determined. Correct Answer: A. The cell will get smaller. Explanation: The solute concentration outside the cell is greater than the solute concentration inside the cell. To reach equilibrium, the solvent particles inside the cell will diffuse through the cell membrane to the outside of the cell until the concentrations inside and outside the cell are equalized. Because solvent particles will leave the cell, the cell will get smaller. You answered this question correctly! 5. A sample of seaweed contains two liters of water and has 100 grams of salt dissolved in its cells. The seaweed is placed in a bucket with 4 liters of water and 300 grams of dissolved salt. What will occur when the system reaches equilibrium? A. The seaweed will absorb 40 grams of salt. B. The seaweed will lose 0.5 liters of water. C. The seaweed will absorb 1.0 liters of water. D. The seaweed will absorb 5.5 liters of water. Correct Answer: B. The seaweed will lose 0.5 liters of water. Explanation: The initial salt concentration in the seaweed is 50 g/L, (100 grams of salt divided by 2 liters), and the salt concentration in the bucket is 75 g/L (300 grams divided by 4 liters). Because the salt concentration is higher outside the seaweed, water will move from the seaweed to the bucket until the salt concentrations are equal. Choice B is the only one that predicts the seaweed will lose water. After losing 0.5 liters of water, there are 1.5 liters of water left in the seaweed and 100 grams of salt, so the salt concentration becomes 66.7 g/L. In the bucket there are now 4.5 liters of water and 300 grams of salt, so the salt concentration in the bucket is also 66.7 g/L. You answered this question correctly!