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diffusion through a membrane ny state lab

 

 

Newbie

Do Now

Read “Diffusion of Water Across a Membrane” in your lab book on pg 5 of the Diffusion through a Membrane lab Part 2. Illustrate a process of diffusion mentioned in the passage.

 

Day 1

Semi-Pro

 

For this part of the lab you will need the following materials:

  • Microscope

  • Red Onion

  • Slide

  • Cover Slip

  • Distilled Water

  • 10% Salt Solution

  • Pipette

  • Paper Towel

 

Watch the following video based on the procedures of the lab. The video shows you how to create a prepared wet mount slide of your sample of onion. During this period you and your group members should be able to complete the following:

  • Illustrate the red onion cell observed under the highest power objective and label the CYTOPLASM, CELL WALL, and CELL MEMBRANE of the red onion cell.

 

  • Apply several drops of 10% salt solution to the prepared slide without disturbing the set-up of the slide. Slowly add the drops of salt water. Once you notice a change... STOP!!!

 

  • Describe the changes you've observed after applying the salt solution.

 

  • Illustrate the red onion cell in 10% salt solution observed under the highest power objective and label the CYTOPLASM, CELL WALL, and CELL MEMBRANE of the red onion cell.

 

  • Describe what happens to the WATER inside of the red onion cell when they are placed in salt water.

 

  • Make sure to clean up your work station!!!

Day 2

 

 

Newbie

Do Now

Summarize the procedures completed so far in Part 2 of Diffusion through the Membrane lab (Procedures 1-11). Read procedure 12. What do you think will happen to the cells?

 

Semi-Pro

 

For this part of the lab you will need the following materials:

  • Microscope

  • Red Onion

  • Slide

  • Cover Slip

  • Distilled Water

  • 10% Salt Solution

  • Pipette

  • Paper Towel

 

 

Today you will complete Part 2 of the Diffusion through a Membrane Lab. Watch the following video based on the procedures of the lab. The video shows you how to create a prepared wet mount slide of your sample of onion. It also shows you how to disturb the environment of the cells and attempt to restore the water content of the cells. During this period you and your group members should be able to complete the following:

  • Create a prepared slide of the red onion cell in 10% salt solution. You should have already illustrated your observations of the red onion cell in 10% salt solution observed under the highest power objective and labeled the CYTOPLASM, CELL WALL, and CELL MEMBRANE of the red onion cell in salt solution. But in case you didn't, make sure to complete this step.

 

  • Apply 20 or more drops of distilled water to the prepared slide without disturbing the set-up of the slide. Once you notice a change... STOP!!!

 

  • Describe the changes you've observed after applying the distilled water.

 

  • Illustrate the red onion cell observed under the highest power objective after restoring the cells with distilled water.

 

  • Make sure to clean up your work station!!!

 

 

 

 

Boss Level

 

Take a look at the Analysis Questions at the end of Part 2 of the Diffusion through a Membrane Lab. Create a picture that illustrates the major idea/ understanding of each analysis question.

Ex) If the question is about diffusion of molecules across the cell membrane I would illustrate the following:

 

 

 

 

 

 

 

 

 

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