Final answer:
The hydrophobic part of the cell membrane arranges itself toward the center to avoid water molecules, as the hydrophobic tails are repelled by water, while the hydrophilic heads interact with it, leading to the formation of a phospholipid bilayer.
Step-by-step explanation:
The hydrophobic part of a phospholipid tends to arrange itself toward the center of the cell membrane in order to avoid water molecules. This is because the hydrophobic (water-fearing) tails of the phospholipids in the cell membrane do not interact well with water. Consequently, these hydrophobic tails face each other, away from the aqueous environment, which is found both inside and outside the cell. On the other hand, the hydrophilic (water-loving) heads interact with the water, facing the aqueous environments that are on the two sides of the membrane.
The cell membrane's structure is critical for its function, with the phospholipid bilayer forming a barrier that separates the watery environments inside and outside of the cell. The hydrophobic tails being in the center of the bilayer allows the membrane to maintain its integrity in a fluid, mostly watery environment.