Keeping in view the “fluid mosaic model” for the structure of cell membrane, which one of the following statement is correct with respect to the movement of lipids and proteins from one lipid monolayer to the other (described as flipflop movement) ?
1) Neither lipids, nor protein can flip-flop
2) While lipids can really flip-flop, proteins cannot
3) While proteins can flip-flop, lipids cannot
4) Both lipids and proteins can flip-flop