Lipids

LIPIDS

  • While individual lipids are not strictly macromolecules, many are built up from smaller monomeric units and they are involved in many macromolecular assemblies.
  • Large lipid molecules are predominantly hydrocarbon in nature and are poorly soluble in water.
  • Some are involved in the storage and transport of energy while others are key components of membranes, protective coats and other cell structures.
  • Glycerides have one, two or three long chain fatty acids esterified to a molecule of glycerol.
  • In animal triglycerides, the fatty acids have no double bonds (saturated) so the chains are linear, the molecules can pack tightly and the resulting fats are solid.
  • Plant oils contain unsaturated fatty acids with one or more double bonds. The angled structures of these chains prevent close packing so they tend to be liquids at room temperature.
  • Membranes contain phospholipids, (which consists of glycerol esterified to two fatty acids and phosphoric acid) spingolipids.
Last modified: Friday, 24 September 2010, 10:37 AM