Why our body does not produce polyunsaturated fatty acids?
Simply, it’s because our bodies add double bonds in MUFAs by delta 9 desaturase which adds double bonds between delta 9 and delta 10 carbons, hence additional double bonds can be formed between existing double bond and the carboxilc group but cannot be formed between the existing double bond and the omega carbon. As a result, our body cannon synthesize parent omega 3 alpha linolenic acid and parent omega 6 linoleic acid, but can form timnadoneic acid which is an omega 3 PUFA