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The process of making a a triacylglycerol (TAG) from free fatty acids (FFA) involves first attaching two fatty acyl groups to a glycerol-3-phosphate backbone to make phosphatidic acid. This process then pauses before phosphatidic acid is dephosphorylated and a third fatty acyl group is added to generate the mature TAG.

What is the advantage of having phosphatidic acid as a precursor to TAG synthesis, as opposed to simply attaching three fatty acyl groups in rapid succession?


Phosphatidic acid serves as a scavenger of inorganic phosphate in the cell.


Phosphatidic acid is a form that can be easily transported across a membrane to complete the TAG generation in a different location.


Phosphatidic acid is a precursor for both TAGs and phospholipids; the extra step allows an opportunity for the precursor to be directed toward whichever product the cell needs most.


Phosphatidic acid donates its phosphate group to ADP to regenerate an ATP as the third fatty acyl group is added.


All of the above are correct.

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