Osmosis Tiered Lesson

Storyboard #3
Observe the completed portion of the storyboard below. Identify the internal and external solutions as isotonic, hypotonic or
hypertonic in the initial, immediate, and final stages. Then write a one sentence explanation about what occurred between the
two particles.
Internal
Cell
Membrane
External
Intermediate
Key: Water: Sugar:
5. This is what I think is happening:___________________________________________________________________
Storyboard #4
Complete the storyboard below showing how the particles will move in order to achieve equal internal and external saltwater
concentrations. Then record a one sentence summary telling what occurred in the storyboard.
Internal
Cell
Membrane
External
Initial
Initial
Intermediate
Key: Water: Salt:
6. This is what I think is happening:___________________________________________________________________
Discussion Questions
7. Osmosis is the diffusion of water. Identify another example of diffusion you have experienced firsthand and explain what
occurred in the process as it was happening. _____________________________________________________________
__________________________________________________________________________________________________
__________________________________________________________________________________________________
8. Living organisms need to maintain a state of balance. What characteristic of life describes balance in an organism?
Explain how the cells in the storyboards achieved a state of balance. ___________________________________________
__________________________________________________________________________________________________
__________________________________________________________________________________________________
9. Based on what you observed in storyboard on question #5, describe how the sugar and water behave once they reach
equilibrium. ________________________________________________________________________________________
__________________________________________________________________________________________________
10. The explanations below were made by two students after observing Storyboard #3.
DeAndre:“I think that the diagrams represent diffusion across the cell membrane and that the liquid is
hypertonic because the sugars don’t move across.”
Madison:“The water wants to move out of the cell by osmosis because there are fewer water molecules outside
the cell compared to inside.”
Which of the students are correct? DeAndre______ Madison______ Both______ Neither______
Explain your answer in paragraph format on an attached sheet of notebook paper.
Final
Final