Fatty Acid Synthesis - (Jul/28/2014 )

I looked up fatty acid synthesis and it says that for saturated fatty acid formation that 6 steps happen with 2 carbon acetyl CoA molecules until palmatic acid which is a 16 carbon fatty acid is formed.

Fatty acids are just carboxylic acids which naturally occur with 4 or more carbons but can have less than 4 carbons. How would all those other fatty acids by length be synthesized because surely 16C fatty acids are not the only ones synthesized.

The synthesis, as you have read, is a cyclic process where the length is increased by two carbons every cycle. If the cycle stops early or goes on, either longer or shorter fatty acid chains are formed.

yeah but I have only read that palmitic acid which is a 16 carbon, straight chain, saturated fatty acid is what is formed during fatty acid synthesis.

Could it be that palmitic acid is the major product but other fatty acids form as well?

Yes, and of course there are also modifications which produce unsaturated versions of these fatty acids.

and modifications for branched chain fatty acids. But then how do the odd numbered ones get formed like a 33C fatty acid for example if 2 carbons are added per cycle?

Via Propionyl-CoA. You can find a lot of infos by googling odd number fatty acid synthesis, e.g. this one: http://www.cliffsnotes.com/sciences/biology/biochemistry-ii/fatty-acid-oxidation/odd-numbered-chain-and-branched-fatty-acids