The Nature of Lipids
Lipids include a vast array of naturally occurring organic molecules. Lipids can be categorized as fats, oils, waxes, cholesterol, cell membranes, some pigments, some vitamins, and many other important compounds. Lipids are molecules that are insoluble in water. Among the many types of lipids, the terms "fat" and "oil" are probably the most familiar. Fats are generally solid at room temperature while oils are liquids. Here we will examine 3 primary classes of lipids: triglycerides, phospholipids, and steroid lipids.