The hydrophobic part of the cell membrane refers to the interior region of the lipid bilayer that does not interact with water. This area is primarily composed of the fatty acid tails of phospholipids, which are long, hydrocarbon chains. These chains are nonpolar and repel water, creating a barrier that separates the aqueous environments both inside and outside the cell.
The structure of the cell membrane is often described by the fluid mosaic model, which illustrates how these lipid molecules form a flexible barrier. The hydrophobic nature of the interior helps to maintain the integrity of the membrane, preventing the free passage of water-soluble substances. This characteristic is crucial for maintaining the cell’s internal environment and allows for the selective permeability of the membrane, which is essential for various cellular processes.