Complex sentence: Ceramides are found in high concentrations within the cell membrane of cells, since they are component lipids that make up sphingomyelin, one of the major lipids in the lipid bilayer.
Split into simpler sentences: Ceramides are found in high concentrations within the cell membrane of cells. They are one of the component lipids that make up sphingomyelin, one of the major lipids in the lipid bilayer.