7: Membranes (part 3: The Fluid Mosaic Model)
There are thousands of proteins and lipids embedded in the phospholipid bilayer of cell membranes, and they carry out very specialized functions depending on their shape.
1) DRAWING LESSON
45 minutes
Finished drawing sample for lesson 7
2) ACTIVITIES
Activity 7.1: ONLINE VIDEO GAME
Here is a great game about cell membranes (uses the parts we’ve been learning about!).
Activity 7.2: Make a paper membrane model
Here are patterns and instructions for making a small section of membrane using card stock paper and colorful chenille stems, which represent proteins embedded in the membrane. (I pulled these pages out of my “Cells” curriculum– ignore references to chapters 2 and 3).
Paper model of bilayer membrane
Activity 7.3: Make an edible fluid mosaic model
You can choose to make either an edible or inedible model
For an edible model, gather a variety of small fruits and/or vegetables. Grapes make nice phospholipid heads. You can cut the grapes in half, and place them on a plate so that they look like a sea of phospholipid heads. You can then use your imagination to add things you might see sticking in or out of a membrane. Perhaps a strawberry, or raspberry, with a vertical hole in it could be an ion channel? Remove some of the grapes and put down a round slice of apple to be a lipid raft. Perhaps a piece of parsley or broccoli could be a polysaccharide sticking up? Use your creativity!
For an inedible model, use a tray filled with water so that your mosaic will actually be fluid. Small marshmallows make nice phospholipid heads, as they float and they are inexpensive. (Soggy marshmallows are technically edible, but I’m not going to advertise this as edible since most people think soggy marshmallows are gross.) Find other things that will float in and around your phospholipids. In the picture you can see that we used toothpicks as little “flags” sticking up. Pieces of styrofoam make good lipid rafts. Use whatever you have on hand.
3) SUPPLEMENTAL VIDEOS
4) QUIZ
If the online quiz is not working, or you need a printed copy of the quiz for any reason, you can find a PDF file on the main module page that lets you print all the quizzes.
