All are PUFAs except:

Ref: Harper i Illustrated Biochemistry, 29th edition. Page no: Pgl42.Explanation:Palnitic acid is 16 carbons containing saturated fatty acid. All Human cells can synthesize palmitic acid from acetyl CoA.Linoieic and Linolenie acid are the nutritionally essential Fatty Acids.Arachidonic acid is semi essential FA, if we take enough of essential fatty acids arachidonic acid can be synthesized in our body, or else this also becomes essential.Note :Arachidonic acid is a PUFA but Arachidic acid is saturated FA. Both contain 20 carbons.Active fatty acid is called as acyl CoA and active acetate is called as acetyl CoA.Eicosonoids are 20 carbons containing physiologi-cally active compounds synthesized from arachidonic acid.