A technique known as freeze-fracture can be used to investigate the structure of cell membranes. The membrane is frozen, and then it is split through the centre, so that the two phospholipid layers separate from each other. Any proteins present in one layer stay within that layer. Proteins that extend across the membrane may be found in either layer after freeze-fracture, depending on the protein’s properties. Which statement(s) about the results of freeze-fracture studies are correct?
- A1, 2 and 3
- B1 and 2 only
- C2 and 3 only
- D1 only