What is the head of a phospholipid comprised of in cell membrane?

The layer of the phospholipid is sandwiched between two protein layers. It is hydrophilic. This will allow water to infiltrate whenever possible. Take note that the tail of the phospholipid is known to be water-fearing.

The phospholipids usually line up and become arranged in parallel layers which can serve as your cell membranes. They are the reason why your cells are working the way that they are working. They also provide the protection that the rest of the cell needs. The tails of the phospholipid are also composed of fatty acids which explain why this part of the phospholipid avoids water.