NOTES

• lipids

  • carbon, hydrogen and oxygen atoms
  • non-polar and hydrophobic(insoluble in water)
  • triglycerides= fats and oils
  • lipids play role in insulation, energy storage, hormonal communication
• triglycerides

  • non polar, hydrophobic molecules
  • monomers= 1 glycerol(alcohol) and 3 fatty acids
  • saturated fatty acids= animal fats, no carbon-carbon double bond and melt at higher temps(solid)
  • unsaturated=plants, contain carbon-carbon double bonds and melt at lower temps(Liquid)
• intermolecular forces are weaker in unsaturated fats(due to kink in double carbon bond, chain not compact)so have a lower melting point

  • saturated fats are solid at room temp and unsaturated are liquid at room temp
• the ester bond

  • triglycerides formed by esterfication
  • ester bonds form when hydroxyl (-OH) group from glycerol bonds with carboxyl (-COOH) group of fatty acid
  • ester bonds form in a condensation reaction, water molecule released from each ester bond
  • for 1 triglyceride, 3 ester bonds so 3 water molecules