Lipids

• Triglycerides are a lipid with three fatty acid tails bonded to a glycerol molecule by ester bonds
• Phospholipids consist of a polar phosphate group head connected to a glycerol and two fatty acid tails
• Esterification is a condensation reaction between molecules in a lipid releasing water
• Saturated lipids have no double bonds in the hydrocarbon tails and are solid at room temperature
• Unsaturated lipids have double bonds in their hydrocarbon tails causing kinking - this means molecules wont lie flat causing them to be liquid at room temperature
• Fats can be used as waterproofing in plants, insulation in cold climate and protection of important organs
• There are a higher ratio of carbon bonds to oxygen in lipids which store more energy in them than carbohydrates
• To test for lipids, mix ethanol with the solution before adding water, if a milky emulsion forms, lipids are present