Lipids

Cards (11)

  • Lipids can provide a source of energy, insulate organisms, and act as waterproofing
  • Triglycerides are a glycerol molecule and 3 fatty acid chains
  • Triglycerides - bonds
    Ester bonds formed by condensation between each of the 3 OH groups on the glycerol and the OH group of each fatty acid chain. Non polar
  • Triglycerides - properties
    Fatty acid chains are hydrophobic making lipids insoluble in water, the hydrophilic heads face outwards and the hydrophobic tails face inwards, the hydrocarbon chains can either be saturated or unsaturated
  • phospholipids are a glycerol molecule, a phosphate group and two fatty acid chains
  • Phospholipids - bonds
    Ester bond formed by condensation between two OH groups on the glycerol and the OH group of each fatty acid chain
  • Phospholipid - properties
    The phosphate group is hydrophilic and the fatty acid chains are hydrophobic, this allows phospholipid to form bilayers which make up membranes in and around cells
  • saturated fatty acids
    Do not have any double bonds between their carbon atoms, it has all the hydrogens it can hold or is saturated with hydrogen
  • Unsaturated fatty acids 

    They have double bonds between carbon atoms which means they contain fewer hydrogen atoms, the double bond also causes the chain to bend/kink, they can contain one or many carbon double bonds
  • Fluid mosaic model
    • is the model used to describe the phospholipid bilayer
    • phospholipid heads are hydrophilic and tails are hydrophobic
    • the centre of the bilayer Is hydrophobic so water soluble substances can’t pass through
  • Advantages of storage
    • lipids are not water soluble
    • does not effect the water potential of cells
    • can be stored in a compact way