Shape and size variation are often required for membrane activity of  biomolecules, however the key property for membrane activity is  the amphiphilic nature of biomolecules. Using Single Chain Mean Field (SCMF) theory for lipid bilayers we show several examples of coupling between membrane activity and variation of conformation of biomolecules and demonstrate that hydrophobic objects embedded into the membrane can be used as lipid ion channels, which open and close pores in lipid bilayers by tuning their shape and size, permeation of lipid bilayers induced by polymers adsorbing at lipid bilayers and how a regular surface patterning of Late Embryogenesis Abundant (LEA) proteins  may facilitate membrane association and control the depth of the equilibrium their penetration  into the bilayer.