Final answer:
The building blocks of phosphatidic acid include glycerol, one phosphate group, and two fatty acids. The molecule's structure, with hydrophilic heads and hydrophobic tails, allows it to form bilayers in cell membranes.
Step-by-step explanation:
The building blocks of phosphatidic acid, a type of phosphoglyceride, are glycerol, one phosphate group, and two fatty acids.
Phosphoglycerides are integral components of cell membranes, composed of a glycerol backbone to which fatty acids are esterified on the first and second carbon atoms. The third carbon atom is bonded to a phosphate group, usually modified by an alcohol. In the case of phosphatidic acid, the phosphate group is not further modified with another compound. This structure confers amphiphilic properties to the molecule, creating a hydrophilic 'head' with the phosphate and a hydrophobic 'tail' with the fatty acids, enabling the formation of bilayers in cell membranes. Typically, one fatty acid is saturated, while the other is unsaturated, contributing to the fluidity and stability of membranes.