change, alter, vary, modify mean to make or become different. change implies making either an essential difference often amounting to a loss of original identity or a substitution of one thing for another. changed the shirt for a larger size; alter implies a difference in some particular respect without suggesting loss of identity.
hydrophilic - having a strong affinity for water; tending to dissolve in, mix with, or be wetted by water. chemical science, chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions.
The hydrophilic heads of phospholipids in a membrane bilayer face outward, contacting the aqueous (watery) fluid both inside and outside the cell. Since water is a polar molecule, it readily forms electrostatic (charge-based) interactions with the phospholipid heads.