Lipids

The word lipid comes from the Greek 'lipos', meaning fat. What unites this chemically diverse group is a shared physical property, not a shared structure: lipids do not dissolve in polar solvents such as water, but dissolve readily in non-polar solvents such as benzene, ether and chloroform. This behaviour arises because lipids contain long hydrocarbon chains, which are non-polar and therefore hydrophobic (water-fearing). The main groups of compounds classified as lipids are triglycerides (fats and oils used mainly for energy storage), phospholipids (the main structural lipid of cell membranes), steroids (ringed …