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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
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Chapter 17 Lipids 17.5Glycerophospholipids
Glycerophospholipids Glycerophospholipidsare • 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
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. Glyceryltrioleate B. Cephalin C. Choline D. Palmitic acid
Solution Identify each as a 1) fatty acid 2) triacylglycerol 3) amino alcohol 4) glycerophospholipid A. Glyceryltrioleate 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 ║ 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 ║ CH2—O—C— (CH2)16—CH3 + O NH3 ║│ Type = cephalin CH2—O—P—O—CH2—CH−COO – │ Serine O– Phosphate Amino alcohol