Past exam of the biochemistry course of the University of Cambridge / 2025 / Paper 5 / Section 1 / 1 / k / Solution

Triton disperses the lipid bilayer into detergent-containing particles, separating the fluorescent lipids enough to remove most fluorescence quenching. Both traces approach the maximum-dilution reference even though their earlier lipid-mixing histories differed. The final fluorescence jump is detergent-induced dequenching, not an additional burst of physiological membrane fusion. It provides a useful normalization endpoint for the available dye signal.