0 Replies Latest reply on Jun 13, 2012 1:18 PM by glen_w

    STEM Snacks - What can you do with an onion?

    glen_w

      onion.jpgMy 7th grade students were learning the parts of cells and had successfully begun using a microscope. As the students became proficient at identifying the cell wall and cytoplasm, I thought it was time to create a different challenge. I showed my students a magnified image from my microscope from my projector. With students watching, a couple of drops of _____ water were placed at the edge of the cover slip. Students were amazed to see the results of this demonstration. (Note the arrow points to the “after image.”)

       

      I invite students to determine what liquid can be used to cause this change in a cell. I have a LOT of liquids as well as materials we can dissolve in water available. My intended purpose is to help students see osmosis happening and understand the process.

       

      • What kind of a solution do you think would cause this change?
      • What other subject areas do you see this applying to?
      • How can an activity like this help a student become more interested in STEM and related careers?