Transportation through Plasma Membrane

Activity:

Activity 1: [Suggested Time: 15 minutes]

Activity Instructions:

1. Observe the simulation (R1) when the teacher is manipulating it.

2. Manipulate the simulation as per the pop-up instructions.

3. Note down the final observations of the experiment. 

4. Can you think of any other real life example similar to what you have observed here?
   
   R1: Imbibition by Raisins - Simulation

   Activity 2: Membrane Channels

   Activity Instructions:
   

   For this simulation we will use the area above the membrane to represent inside the cell and the area at the bottom to represent outside of the cell. (This can be written on the IFP as it is not mentioned in the simulation.)

   Let the blue diamond’s represent water molecules while the green dots will represent a solute, like salt. Cells need to transport both these things across their membranes.

   Green dots:_____________

   Blue diamonds:_____________

    

   Part One:

   Add 20 green dots to the inside of the cell and 10 green dots to the outside of the cell.

5. Where is the concentration of sodium higher?

6. Where is the concentration lower? 

7. Add three green leakage channels (evenly spaced)

8. What do you think, how will the green dots move once you start the simulation?

9. Run the simulation for 15 seconds and then press the pause button. 

10. Count the number of green dots inside the cell and outside of the cell

11. Inside:                                 Outside:

12. Run the simulation for 15 more seconds and count again:

13. Inside: Outside:

    6. What was the net movement of dots? (Think about the initial concentrations)

    7. Based on your observations, define diffusion:

     

    Part Two

    Clear all of the particle from the simulation by pressing reset button and add the following molecules:

     

    Inside Cell: Outside Cell:

    Water Molecules: 5                                                   Water molecules: 20

    Sodium ions: 20 Sodium ions: 5

14. You have created a solution containing water and salt. In this case, what is the solute and what is the solvent?

15. Comparing the amount of water and salt molecules, which side of the membrane has the more concentrated salt solution?

16. Which side has the more dilute salt concentration?

17. Which side has higher water concentration?

18. Which side has lower water concentration?
19. Open up the gates and run the simulation. Count the number of water molecules and salt molecules at the following times:

The above table can be made in notebooks by the students.

1. What was the net movement of the green dots? High to low concentration or low to high?

2. Osmosis is a special word that describes the diffusion of water molecules across a membrane. Based on your observations, what was the net movement of water in regards to concentration of solutions?

3. In case of imbibition the water molecules move because of capillary action. Imbibition occurs due to the attractive forces between the liquid and the solid surface, which pull the liquid into the material.

4. Diffusion occurs due to the random motion of particles, and it aims to equalise the concentration of particles throughout a system. It is a random process.

5. Osmosis is a specific type of diffusion that involves the movement of solvent molecules (usually water) across a semipermeable membrane from an area of lower solute concentration to an area of higher solute concentration. This movement continues until the concentration of solute on both sides of the membrane is equal.

6. Add two blue gated channels and two green gated channels. 

R2: Membrane Channels - Simulation

​​​​​​Assessment: Activity 3

Activity Instructions:

1. Answer the Multiple Choice Questions in R6. 

R3: Viva Voice - MCQ

Homework: 

Search for real life examples and uses of diffusion.

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