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The cell membrane and how it has changed over the years. - Coggle Diagram

- - - - This had taught them that the cell membrane must be a bilayer of phospholipids with the hydrophobic lipid tales tucked in the middle away from the water while the hydrophilic heads are on the outside so they can be constantly exposed to water.
- - - - One of these issues is that proteins are not all uniform, as they have many different structures to be able to complete many different processes. Also because the proteins are sandwiching the phospholipids, the hydrophilic phosphate head is not able to make connections to H20, which is not possible. Also is the protein is so uniform it makes it impossible for materials to diffuse in and out of the cell membrane.
- - - - This is where you rapidly freeze and then split the cell. The cell will break along its most vulnerable point, in this case between the phospholipid bilayer of the cell membrane. They found that the cell membrane was not smooth as Davson and Danielli would assume. Instead they found that there was a irregular roufh surface. This falsifies the Davson and Danielli as these random bumps where interpreted as transmembrane protiens, demonstrating that proteins where not solely localised to the outside of the membrane structure,
      - $freeze fracturing 2$
    - - where they take membrane protein from two different species, in this case a mouse and a human. They tagged them separately with red and green florescent markers. They fuse the two cells, expecting the markers to stay to their respective signs. However they found that the proteins mixed together. This shows that the membranes are not static layers as Davson and Danielli suggested.