Pathways for endogenous elongation and desaturation of 18:2n-6 and 18:3n-3 to produce n-6 and n-3 long chain polyunsaturated fatty acids, respectively.

<p>The enzymatic system acts on both pathways in parallel requiring Δ6 and Δ5 desaturases and fatty acyl elongases 2 and 5. Elong, fatty acyl elongase.