How is the plasma membrane of a cell organized?
Question 15 options:

one layer of phospholipids, through which proteins freely move

one layer of phospholipids, which are laid out end-to-end, with a hydrophobic tail touching a hydrophilic head

two layers of phospholipids, each of which has its hydrophilic side turned inward

two layers of phospholipids, with their polar hydrophilic heads facing away from each other