Lipids are fats and fat-like substances. First of all lipids, which are not actually fats, called lipids; this term has expired. Lipids are found in plants, animals and microorganisms. Common property of lipids is the insolubility in water solubility in organic solvent (ether, benzene, chloroform, tetrachloride carbon and other). Lipids are divided into: 1) simple lipids, which are actually fats (see) and waxes - esters of fatty acids and monatomic alcohols; 2) complex lipids that, except alcohols and fatty acids contain other groups, such as nitrogenous bases, and phosphoric acid, phospholipids, or phosphatides (see), carbohydrates (glycolipids), etc.; 3) other lipids of the fatty acid, mono - and diglycerides, sterols (see), steroids and other Lipids are essential reserve of energy for organisms (see Fat metabolism). In addition, many of them play an important specific role, for example in the structure of biological membranes. To steroids are some hormones, vitamins, bile acids and other biologically important substances. Cm. also Lecithins, the Cerebrosides.

Lipids (from the Greek. lipos - fat) is a group of compounds that differ in their chemical structure, content in the body of animals, plants and microbes and biological role, but have some similar physico-chemical properties (the insolubility in water and aqueous salt solutions, solubility in organic solvents - benzene, chloroform, ether, alcohol, acetone). The term "lipids" is more General than the term "lipids", which brings together a group of so-called fat-like substances (phosphatides, cerebrosides, waxes and other), but not true fats (triglycerides).
Are distinguished: 1) simple lipids, 2) a complex of lipids and 3) L. derivative among the simple L. are esters of fatty acids with various alcohols (true fats are esters of fatty acids and glycerine), waxes (esters of fatty acids and cetyl or other monatomic alcohols with long straight chain), ethers of fat acids and cholesterol (steady and cholesteric), esters of vitamin palmitic or stearic acids, ethers of Complex vitamin D. L., excluding esters of fatty acids and alcohols contain other groups. To the complex include L. phosphatides (see) or phospholipids [esters of fatty acids from the glycerin, which are attached to various nitrogenous base (choline, ethanolamine) or Inositol and phosphoric acid] and glycolipids, or cerebrosides (see), which are composed of fatty acids (Ognianova, Cherepanova, Neronova), nitrogenous bases (sphingosine, digidropiridina) and sugar (galactose). To glycolipids are also gangliosides (found in the gray matter of the brain; consist of sphingosine, stearic acid, neuraminic acid and hexoses) and sulfatide (cerebrosides, with the remaining sulfuric acid).
Derivatives of simple and complex lipids (or the breakdown products of substances contained in them), some free sterols and other compounds with common with the Leningrad physico-chemical properties form the third group of lipids. This is diglycerides, monoglycerides and free fatty acids, formed by the disintegration of fats, high molecular weight alcohols with long straight chain, which are products of the fission waxes, alcohols containing IP ring (vitamin a-alcohol and a number of carotene), available sterols (cholesterol, vitamin D, vitamin E and K, as well as a number of glucosides plant steroids, particularly glucosides digitalis and saponins, and some intermediate products of synthesis of sterols (hydrocarbon squalene).
From soybean oil allocated fraction of lipids, composed of glycerol and fatty acids, phosphoric acid, Inositol, ethanolamine, galactose, arabinose and tartaric acid and called opositora. Liposinol is part of the brain and spinal cord.