Abstract
Although serum cholesterol level is closely related to atherosclerotic disease, cholesterol and its derivatives are important components of cell membranes, steroid hormones, bile acids and vitamin D. It remains unsolved why mammals developmentally selected cholesterol, but not other sterols as a regulatory component of biomembranes. This article describes the importance of cholesterol in mammalian cells from the biochemical as well as physicochemical aspects. The effects of oxidized cholesterol on metabolic functions are also briefly discussed.
