fatty acid biosynthetic pathway fatty acid elongation pathway 2012-11-02T15:26:41Z PW:0001136 The C16 palmitate product of the fatty acid biosynthetic pathway can be esterifed to triacylglycerol or converted to longer chain saturated and unsaturated fatty acid molecules by elongases and desaturases, depending on the needs of the cell. The elongation pathway takes place in the endoplasmic reticulum or in the mitochondrion. Longer chain fatty acids are present in certain specialized tissues; for instance, myelin contains large amounts of C22 and C24 molecules. fatty acid elongation pathway vpetri