Fig 3.
Structures of the two classes of polyunsaturated fatty acids. The omega 3 fatty acids have their first double bond at the third carbon molecule from the methyl (CH3) end of the fatty acid, whereas the omega 6 fatty acids have their first double bond at the sixth carbon molecule. The chemical names for each fatty acid are also given: the number of carbon atoms is given first, followed by the number of double bonds and the position of the first double bond. Omega 6 linoleic acid can be desaturated in certain plants to form omega 3 α linolenic acid. Whereas linoleic acid is mainly converted into arachidonic acid, α linolenic is elongated and desaturated into eicosapentanoic acid and then docosahexanoic acid