17.5 Glycerophospholipids Chapter 17 Lipids 17.5 Glycerophospholipids

Glycerophospholipids Glycerophospholipids are the most abundant lipids in cell membranes composed of glycerol, two fatty acids, phosphate, and an amino alcohol

Glycerophospholipids Are Polar A glycerophospholipid has two nonpolar fatty acid chains a phosphate group one of three polar amino alcohols

Structure and Polarity of a Glycerophospholipid

Lecithin and Cephalin Lecithin and cephalin are glycerophospholipids that are abundant in brain and nerve tissues are found in egg yolk, wheat germ, and yeast contain choline (in lecithins) or either ethanolamine or serine (in cephalins)

Learning Check Identify each as a 1) fatty acid 2) triacylglycerol 3) amino alcohol 4) glycerophospholipid A. Glyceryl trioleate B. Cephalin C. Choline D. Palmitic acid

Solution Identify each as a 1) fatty acid 2) triacylglycerol 3) amino alcohol 4) glycerophospholipid A. Glyceryl trioleate 2) triacylglycerol B. Cephalin 4) glycerophospholipid C. Choline 3) amino alcohol D. Palmitic acid 1) fatty acid

Learning Check Identify the components and type of glycerophospholipid: O ║ CH2—O—C— (CH2)16—CH3 + O NH3 ║ │ CH2—O—P—O—CH2—CH−COO – │ O–

Solution Identify the components and type of glycerophospholipid: O ║ CH2—O—C— (CH2)16—CH3 O 2 Stearic acids + O NH3 ║ │ Type = cephalin CH2—O—P—O—CH2—CH−COO – │ Serine O– Phosphate Amino alcohol