Chapter 8A - Fats and Oils

• group of compounds called lipids • made up of large non-polar molecules called triglycerides

• energy source • insulation • protection of organs • transport of fat-soluble vitamins

• major type of lipid in the human body • large biomolecules • formed through condensation b/w glycerol & 3 fatty acid molecules

• contains 3 ester links (triester) • non-polar with weak dispersion forces • insoluble in water

Long chain carboxylic acids

• saturated fatty acids (C-C bonds) • solid at room temperature: molecule pack close together creating stronger dispersion forces between chains • derived from animals

• unsaturated fatty acids • liquid at room temperature: contain C=C bonds causing “kinks” so can’t pack as close together, resulting in weaker dispersion forces between chains • unstable at room temperature as they are oxidised easily (due to unsaturation hence more reactive) • derived from plants

One C=C bond

More than one C=C bond

• triglycerides are digested (broken down) in body to produce glycerol & 3 fatty acids • breaks the ester links • MUST BE IN THE PRESENCE OF ENZYMES • fatty acids produced are oxidised to produce carbon dioxide & water

Excess triglycerides are stroed in adipose tissue as a long-term energy source.