All cells have surface membranes and maintaining the surface area of this membrane is critical to the normal functioning of cells. The surface membranes of cells lining our lungs, guts and the light-sensing cells of our eyes undergo constant recycling to operate effectively. Using the light-sensitive membranes in fruit fly eyes as a model system, have recently identified an enzyme named Phospholipase D or PLD — that is essential for recycling of membranes for normal sight.