lipids

• There are 2 types of lipids: triglycerides and phospholipids
• Trigylcerides are formed in a condensation reaction between 1 glycerol molecule and 3 fatty acids. They form ester bonds
• The main uses of triglycerides are for waterproofing, thermal insulation and as an energy store.
• The structure of triglycerides are that they have an insoluble hydrocarbon chain. This helps with waterproofing as it doesnt have an osmotic effect.
• Triglycerides also are slow heat conductors which helps provide thermal insulation for animals. They have a high energy:mass ratio which helps it in being a good energy store.
• Phospholipids have a similar structure to triglycerides but 1 phosphate group replaces 1 fatty acid chain.
• the structure of a phospholipid is that it has 2 fatty acid chains and 1 phosphate head attached to a glycerol backbone. The fatty acid tails are hydrophobic and the phosphate head is hydrophilic.
• Phospholipids form bilayers in water where the tails face outwards and the heads
• phospholipids form bilayers in water where the head faces inwards and the tail faces outwards. They are the component of cell membranes.
• Unsaturated lipids contain carbon double bonds. They have a lower m.p and are kinked.
• Saturated lipids have carbon single bonds and a higher m.p. They are solid at room temperature and straight chained