lipids

• are Lipids organic or inorganic compounds?

  organic compounds
• elements found in lipids


  carbon, hydrogen and oxygen
• lipids ratio hydrogen to oxygen

  H:O > 2:1
• monomers of lipids


  glycerol and fatty acids
• what is a fatty acid?

  a long chain of Carbon and hydrogen with COOH (acid group) at one end
• where are unsaturated acids found?

  plants
• where are saturated acids found?

  animals
• examples of unsaturated fatty acids


  sunflower and olive oil
• examples of saturated fatty acids


  butter and lard
• unsaturated fatty acids are liquid at room temperature
• saturated fatty acids are solid at room temperature
• bad parts of saturated fatty acid

  linked to heart disease and cholesterol
• explain build up of unsaturated fatty acids

  contain double bonds between some carbon molecules
• explain build up of saturated fatty acids


  have single bonds between all carbon molecules
• larger molecules of lipids

  fats and oils
• what are fats


  solid at room temperature
• examples of fats


  butter (hard=saturated) and margarine (soft=unsaturated)
• what are oils


  liquid at room temperature and insoluble in water but they dissolve in other lipids
• glycerol --> 3 fatty acids --> lipid + 3H2O
• what are glycerol and fatty acids bonded by

  ester bonds
• explain the translucency test

  dissolve lipid in an organic solvent (ethanol, methanol) then poure onto filter paper, greasy stain = positive result
• biological importance of lipids

  -reserve energy store

  -layer under the skin (adipose tissue + blubber) used for insulation(keeping the body warm)

  -found in cell-membrane (phospholipids) and plays an important role in controlling their permeability

  -found around internal organ to provide protection