Final answer:
A phospholipid molecule features a hydrophilic head made of a phosphate group and a hydrophobic tail consisting of two fatty acids, making it an amphiphilic substance crucial for forming cell membrane bilayers.
Step-by-step explanation:
The phospholipid molecule is a major component of cell membranes, characterized by its amphiphilic nature, meaning it has regions that are attracted to water (hydrophilic) and regions that repel water (hydrophobic). Structurally, it is composed of a glycerol backbone to which two fatty acids are attached, forming the hydrophobic tails, and a phosphate-containing group attached to the third carbon, forming the hydrophilic head. The ability of the polar head to form hydrogen bonds and the nonpolar tails to avoid water allows phospholipids to form unique structures like bilayers in cell membranes, which are critical for protecting and organizing cells.