第二章 脂类（Second chapter lipids）.docVIP

第二章 脂类（Second chapter lipids） The second chapter is lipid Lipids Emphasis: phospholipids, glycolipids First, the concept of lipid A compound that is insoluble in water and is pumped by non-polar organic solvents such as ether, chloroform, and benzene; collectively called lipids. Lipids include fats (glycerol, three lipids) and lipids (phospholipids, waxes, terpenes, and steroids). Two, classification Dan Chunzhi: (1) fatty acids and alcohols esters, glycerol ester, sphingolipids and wax (2) compound lipid: Glycerin, lecithin and sphingomyelin. (3) terpenoids and steroids and their derivatives: no fatty acids, all of which are derivatives of isoprene. (4) derived lipids: the hydrolysis products of these lipids, including fatty acids and their derivatives, glycerol, sphingosine, etc.. (5) binding lipids: glycolipids and lipoproteins Three. Biological function of lipids The biological functions of lipids are also varied: The structure of the biological membrane of group (glycerol phospholipids and sphingomyelin, cholesterol and glycolipids); the energy storage forms (animal, oil seeds; triglyceride) precursor the hormones, vitamins and pigments (terpenes, sterols); the growth factor; the antioxidant; the chemical signals (such as 7); involved in signal recognition and immune (glycolipids); the animal fat tissue with insulation, anti mechanical pressure protection function of plant wax can prevent water evaporation. Section 1 fatty acids and their derivatives Fatty acids Most fatty acids contain even numbered carbon atoms, forming chains that grow without branching (also branched or containing a ring of fatty acids). There are two different kinds of unsaturated fatty acids, CIS and trans. Most organisms, however, are CIS structures. In unsaturated fatty acids, trans double bonds can cause fatty acid chains to bend, and molecules do not bind as tightly as the saturated fatty acid chains. Thus, the melting point of unsaturated fatty acids is low. Fatty acids (mainly myri